Updated CET data base v2.0 posted (9 May 2022) -- an ongoing analysis of changes made to what they now call the "legacy" data base

[Roger J Smith]

As to what I meant in the quoted comment, partly one, mostly the other ... check out what happened in the daily records in Jan-Feb which is as far as I got, and the weaker members of the old herd of record warm days has been picked over by the recent past as noted. It is what it is, only Mr Legg and company know for sure how innocent these changes may be. You can be pretty sure that climate change skeptics will note the implication of the changes to record values, as will climate change "advocates" (to use a polite term). Having said that, I am on the fence about this, I could imagine a scenario where older warm records got the full treatment and no more May 1833 or April 1775 etc etc. The changes are subtle and whether anyone was aware of changing records (it is our fascination here maybe more than where Legg works) or not is an open question. Maybe they didn't have top of mind awareness of old records like readers of this thread might have. 

To the point made by CM, there is a supporting document explaining the changes, and somebody earlier on provided a link to that. The overall concept is that they wanted to homogenize the series more so than previously the case. 

Compare and contrast, the record lows are almost completely intact as many of them were well below contenders so any slight adjustments (since 1853, and many were before that anyway) made no difference. The only change other than numerical values is that one daily tie between 1895 and 1917 has been changed to a solo record for 1895.

But there are about ten changes to record highs out of sixty, most going towards the idea of more recent warm records. (this is only a study of daily means so far, have not even looked at the max and min data yet) ...

 

LEGACY CET DAILY RECORDS with v2.0 changes noted 

... underlined are new ties, bold type show new records that have replaced older ones

 

Jan-Feb daily records (Legacy) _____ Jan-Feb daily records (v2.0)

01 Jan ... 12.6 (2022) ... -5.9 (1820) ... ... ... 12.7 (2022) ... ... -5.9 (1820)

02 Jan ... 10.4 (1948) ... -6.1 (1786) ... ... ... 10.4 (1922,48) ... -6.1 (1786)

03 Jan ... 11.6 (1932) ... -7.7 (1795) ... ... ... 11.5 (1932) ... ... -7.7 (1795)

04 Jan ... 10.5 (1948) ... -9.3 (1867) ... ... ... 10.4 (1948) ... ... -9.0 (1867)

05 Jan ... 11.4 (1957) ... -6.5 (1789) ... ... ... 11.3 (1957) ... ... -6.5 (1789)

06 Jan ... 10.3 (1898) ... -6.9 (1894) ... ... ... 10.4 (1898) ... ... -7.0 (1894)

07 Jan ... 10.3 (1890) ... -7.7 (1841) ... ... ... 10.4 (1890) ... ... -7.7 (1841)

08 Jan ..... 9.9 (1858.)... -9.2 (1841) ... ... ... ..9.7 (1775,1858) .. -9.2 (1841)

09 Jan ... 10.7 (1998) ... -5.0 (1841) ... ... ... 10.6 (1998) ... ... -5.0 (1841)

10 Jan ... 11.1 (1921) ... -6.7 (1814) ... ... ... 11.2 (1921) ... ... -6.7 (1814)

11 Jan ... 10.1 (1990) ... -5.5 (1838) ... ... ... 10.1 (1990) ... ... -5.5 (1838)

12 Jan ... 9.9 (1976,2007) .. -7.7 (1987) ... ... 9.9 (1976,2007) .. -7.7 (1987)

13 Jan ...10.0 (1796,1873) .. -6.6 (1987) ... 10.0 (1796, 2007)^ .. -6.6 (1987)

14 Jan ... 10.2 (2011) ... -7.6 (1982) ... ... ... 10.2 (2011) ... ... -7.5 (1982)

15 Jan ... 10.3 (1804) ... -8.5 (1820) ... ... ... 10.3 (1804) ... ... -8.5 (1820)

16 Jan ... 10.8 (1990) ... -7.7 (1881) ... ... ... 10.8 (1990) ... ... -7.4 (1881)

17 Jan ... 10.2 (1908) ... -6.2 (1881) ... ... ... 10.2 (1908) ... ... -6.9 (1881)

18 Jan ... 10.0 (1828) ... -6.1 (1891) ... ... ... 10.0 (1828) ... ... -6.2 (1891)

19 Jan ... 11.1 (1930) ... -8.9 (1823) ... ... ... 11.2 (1930) ... ... -8.9 (1823)

20 Jan ... 11.2 (2008) .. -11.9 (1838) ... ... ...11.2 (2008) ... ...-11.9 (1838)

21 Jan ... 10.8 (1796,1898).. -8.1 (1881) ... 10.8 (1796)^... ... -8.0 (1881)

22 Jan ... 10.3 (1878) ... -6.4 (1881) ... ... ... 10.2 (1969)^ ... ... -6.5 (1881)

23 Jan ... 11.6 (1834) ... -8.4 (1963) ... ... ... 11.6 (1834) ... ... -8.4 (1963)

24 Jan ... 10.6 (1782) ... -8.2 (1963) ... ... ... 10.6 (1782) ... ... -8.2 (1963)

25 Jan ... 11.6 (2016) ... -8.9 (1795) ... ... ... 11.6 (2016) ... ... -8.9 (1795)

26 Jan ... 10.0 (1834) ... -7.6 (1945) ... ... ... 10.0 (1834) ... ... -7.6 (1945)

27 Jan ... 10.5 (2016) ... -6.5 (1776) ... ... ... 10.5 (2016) ... ... -6.5 (1776)

28 Jan ..... 9.8 (1944) ... -6.3 (1776) ... ... ... .. 9.7 (1944,1983)^ .. -6.3 (1776)

29 Jan ... 10.4 (1854) ... -6.8 (1776) ... ... ... 10.2 (1854,1966)^ .. -6.8 (1776)

30 Jan ... 10.2 (2000) ... -7.5 (1776) ... ... ... 10.2 (2000) ... ... -7.5 (1776)

31 Jan ... 10.9 (1868) ... -7.2 (1776) ... ... ... 10.7 (1868) ... ... -7.2 (1776)

01 Feb ... 11.4 (1923) ... -6.8 (1956) ... ... ... 11.1 (1923) ... ... -6.8 (1956)

02 Feb ... 11.0 (1923) ... -6.5 (1956) ... ... ... 10.9 (2002,2004)^.. -6.4 (1956)

03 Feb ... 12.2 (2004) ... -5.4 (1841,1956) ... 12.2 (2004) .. -5.4 (1841,1956)

04 Feb ... 12.8 (2004) ... -5.0 (1912) ... ... ... 12.8 (2004) ... ... -4.8 (1912)

05 Feb ... 11.8 (2004) ... -6.3 (1830) ... ... ... 11.8 (2004) ... ... -6.3 (1830)

06 Feb ... 10.3 (1866) ... -7.3 (1895) ... ... ... 10.3 (2011)^.. ... -7.2 (1895)

07 Feb ... 10.5 (1869) ... -7.2 (1895 & 1917) ... 10.4 (1869) .. -7.6 (1895)^

08 Feb ... 11.4 (1903) ... -8.3 (1895) ... ... ... 10.7 (1903) ... ... -8.5 (1895)

09 Feb ... 11.4 (1831) ... -8.8 (1816) ... ... ... 11.4 (1831,1903)^ .. -8.8 (1816)

10 Feb ... 12.0 (1899) ... -6.2 (1895) ... ... ... 12.1 (1899) ... ... -6.6 (1895)

11 Feb ... 11.4 (1939) ... -4.2 (1986) ... ... ... 11.4 (1939) ... ... -4.0 (1986)

12 Feb ... 11.4 (1998) ... -7.7 (1845) ... ... ... 11.3 (1998) ... ... -7.7 (1845)

13 Feb ... 12.0 (1998) ... -7.0 (1929) ... ... ... 11.9 (1998) ... ... -6.9 (1929)

14 Feb ... 10.2 (1794) ... -7.1 (1929) ... ... ... 10.2 (1794) ... ... -7.2 (1929)

15 Feb ... 11.2 (1958) ... -8.0 (1929) ... ... ... 13.7 (2024)^... ... -7.4 (1929)

16 Feb ... 10.3 (2022) ... -7.3 (1855) ... ... ... 10.5 (2022) ... ... -7.2 (1855)

17 Feb ... 10.7 (1878) ... -7.1 (1855) ... ... ...11.3 (1878, 2023)^...-7.0 (1855)

18 Feb ... 11.7 (1945) ... -3.9 (1855) ... ... ... 11.8 (1945) ... ... -3.9 (1855)

19 Feb ... 10.6 (1893) ... -5.0 (1777) ... ... ... 10.4 (1893) ... ... -5.0 (1777)^

20 Feb ... 11.3 (1990) ... -6.6 (1785) ... ... ... 11.3 (1990) ... ... -6.6 (1785)

21 Feb ... 11.2 (2019) ... -4.7 (1810) ... ... ... 11.3 (2019) ... ... -4.7 (1810)

22 Feb ... 10.7 (1953) ... -3.3 (1855) ... ... ... 10.6 (1953) ... ... -3.3 (1855)

23 Feb ... 11.7 (2012) ... -3.5 (1947) ... ... ... 11.8 (2012) ... ... -3.5 (1947)

24 Feb ... 11.4 (1846) ... -6.7 (1947) ... ... ... 11.5 (2021)^... ... -6.6 (1947)

25 Feb ... 11.0 (1922) ... -5.1 (1947) ... ... ... 10.9 (1922) ... ... -5.1 (1947)

26 Feb ... 11.2 (1882) ... -4.7 (1783) ... ... ... 10.9 (1882) ... ... -4.7 (1783)

27 Feb ... 11.5 (1828) ... -2.8 (1929) ... ... ... 11.5 (1828) ... ... -2.8 (1929)

28 Feb ... 11.4 (1959) ... -3.8 (1785) ... ... ... 11.4 (1959) ... ... -3.8 (1785) .. 2018 now -3.5

29 Feb ... 12.0 (1960) ... -2.4 (1904) ... ... ... 12.0 (1960) ... ... -2.0 (1904)

___________________________________________

^ notes: 

13 Jan 1873 lost tie with drop to 9.9, 2007 gained tie with increase 9.9 to 10.0 (1796 unchanged at 10.0)

21 Jan 1898 lost tie with drop to 10.7

22 Jan 1878 lost record to 1969 with drop to 9.8 from previous record 10.3 (1969 up from 10.2)

28 Jan 1983 gained tie as 1944 went from 9.8 to 9.7 (1983 unchanged at 9.7). 

29 Jan 1966 gained tie as 1854 went from 10.4 to 10.2 (1966 unchanged at 10.2). 

 2 Feb 2002,2004 gained tied record from 1923 which changed from 11.0 to 10.7 (2002,04 unchanged)

 6 Feb 1866 lost record to 2011. 1866 dropped from 10.4 to 10.2, 2011 went up from 10.1 to 10.3. 

 7 Feb 1917 lost tied cold record with 1895, which went from -7.2 to -7.6 while 1917 went to -6.2. 

 9 Feb 1903 gained tie with 1831, increase from 11.2 to 11.4 (8 Feb 1903 held on to record despite 11.4 to 10.7 drop).

15 Feb 2024 new record, broke 11.1 C 1958 (v2.0). Is also new February record. 

17 Feb 2023 tied 1878 in v2.0 (11.3) after 1878 was boosted from its legacy value of 10.7 C. 

19 Feb 1892 almost tied 1777 by moving from -4.7 to -4.9. Closest call for any new cold record (added rather than dropped).

24 Feb 2021 gained record (11.3 to 11.5) and 1846 lost it (11.4 unchanged). 

__________________________________________________

I looked at 1st March 2018 and it holds on despite a change from -3.8 to -3.7; it had the same change to 28 Feb where it was 

already 0.2 above the record and is now 0.3 above the 1785 record (-3.8) for 28 Feb (went from -3.6 to -3.5). 

... will post similar tables in two-month intervals hopefully faster than every two days but that might be close to it with a weekend looming.

Edited February 19 by Roger J Smith

[Thundery wintry showers]

I think there were some issues with the "legacy" CET records, in particular a slight cool bias from around 2008 onwards, so I think they were right to produce this updated version and to keep the legacy records available.  But I certainly see the point that some of us (myself included) memorised many of the old monthly and annual CET values and now some of them have changed, making it feel like the end of an era.

The change that I definitely don't like is quoting annual values to 1 rather than 2 decimal places.  For example, the year 1995 has gone from CET 10.55 to 10.5, and I have a suspicion that it's now 10.5 rounded up from 10.4*, because several of the monthly values for 1995 had 0.1-0.2C chopped off.  (The late Philip Eden's CET value for 1995 was 10.47 if I remember correctly).  While this can easily be done in Excel it would've been nice to be able to directly compare values to the same number of decimal places in separate tabs.

I wasn't surprised to see March 1995 drop to 5.5, as the CET of 5.6 (-0.1 relative to 1961-90) always seemed a little high to me considering that most sites in England had a negative temperature anomaly relative to 1961-90 that month.  Likewise for the polar maritime dominated month of December 1999 (5.0 down to 4.8).  July 2006 going up from 19.7 to 19.8 was a slight surprise.

The big surprise for me was December 2000 going from 5.8 to 5.3.  I'd have expected a downward adjustment to that month, possibly to 5.6 or even 5.5, but the drop to 5.3 is such a large step that I'm wondering if there was a glitch.

As an aside, it's a shame that neither Philip Eden nor his Climate-uk site are with us any longer as it would have been interesting to compare the new Met Office series with his alternative series.  I have a strong suspicion (based partly on my memories of Philip Eden's series) that the Met Office version 2.0 would generally be closer to his series but still with some slight differences.

Edited May 13, 2022 by Thundery wintry showers

[Roger J Smith]

Continuing on with the updated records, this post for March and April ... this was a bit more balanced with some records changing from newer dates to older ones, as well as a few more of the older ones being downgraded and/or replaced by boosted newer ones. There is more action on the cold side also. All changes to records are explained in the notes. 

(just a reminder that all record temperatures set 1772-1852 are unchanged, so for them to lose status they would need to be followed by some other year that had a favourable adjustment which rarely happens ... and in one case one of these older values became a new record when the more modern one was adjusted down, that being 26 Apr 1928 falling to 1821 ... most of the older records falling to newer values have been in the period 1853 to 1930 where they can be adjusted down, or a more recent one adjusted up ... the changes in record low values do not show much of an organized pattern). 

 

 

LEGACY CET DAILY RECORDS with v2.0 changes noted 

... underlined are new ties, bold type show new records that have replaced older (or newer) ones

 

Mar-Apr daily records (Legacy) _____ Mar-Apr daily records (v2.0)

 

01 Mar ... 10.7 (1878.) ... -3.8 (2018.)... ...10.9 (1878.) .. -3.7 (2018.)
02 Mar ... 11.1 (1777) ... -3.2 (1965) ... ... 11.1 (1777) ... -3.1 (1965)
03 Mar ... 11.0 (1777) ... -3.9 (1965) ... ... 11.0 (1777) ... -3.8 (1965)
04 Mar ... 12.3 (1859) ... -2.9 (1909) ... ... 12.3 (1859) ... -2.8 (1845)^
05 Mar ... 10.9 (1834) ... -2.8 (1786&1909) .. 10.9 (1834) .. -2.8 (1786)^

06 Mar ... 12.0 (1989) ... -4.7 (1786) ... ... 12.0 (1989) ... -4.7 (1786)
07 Mar ... 10.9 (1875) ... -3.3 (1947) ... ... 10.8 (2014)^ .. -3.3 (1947)
08 Mar ... 12.2 (2000) ... -3.1 (1786) ... ... 12.1 (2000) ... -3.1 (1786)
09 Mar ... 12.4 (1948) ... -3.0 (1917) ... ... 12.5 (1948) ... -2.6 (1917)
10 Mar ... 11.6 (1957) ... -2.4 (1883) ... ... 11.5 (1957) ... -2.1 (1883)

11 Mar ... 12.6 (1957) ... -1.9 (1847) ... ... 12.6 (1957) ... -1.9 (1847)
12 Mar ... 13.4 (1957) ... -2.4 (1785) ... ... 13.4 (1957) ... -2.4 (1785)
13 Mar ... 12.8 (1991) ... -6.5 (1845) ... ... 12.8 (1991) ... -6.5 (1845)
14 Mar ... 11.5 (1805) ... -3.7 (1845) ... ... 12.1 (2024)^... -3.7 (1845)
15 Mar ... 11.9 (1884) ... -1.6 (1867) ... ... 12.0 (1884) ... -1.5 (1845&1867)^

16 Mar ... 13.2 (2004) ... -3.0 (1845) ... ... 13.2 (2004) ... -3.0 (1845)
17 Mar ... 13.2 (2005) ... -2.2 (1845) ... ... 13.1 (2005) ... -2.2 (1845)
18 Mar ... 14.1 (1990) ... -1.3 (1853) ... ... 14.2 (1990) ... -1.1 (1853)^
19 Mar ... 11.8 (1822) ... -0.9 (1814) ... ... 11.8 (1822) ... -0.9 (1814)
20 Mar ... 12.3 (1779) ... -1.6 (1845) ... ... 12.3 (1779) ... -1.6 (1845)

21 Mar ... 11.7 (1927,31) ... -1.6 (1899) ... 11.7 (1927,31,2002)^ ... -1.6 (1899) 
22 Mar ... 12.6 (1903) ... -0.9 (1837) ... ... 12.2 (1927)^ ... -0.9 (1837)
23 Mar ... 12.1 (1852,1945) .. -0.8 (1837&1899) .. 12.4 (1886)^ .. -0.8 (1837)^
24 Mar ... 13.4 (1776) ... -0.6 (1879) ... ... 13.4 (1776) ... -0.6 (1879)
25 Mar ... 13.9 (1777) ... -1.3 (1853) ... ... 13.9 (1777) ... -1.1 (1853)

26 Mar ... 14.6 (1777) ... -0.3 (1879&1901) .. 14.6 (1777) ... -0.3 (1879)^
27 Mar ... 14.8 (1777)..... 0.1 (1901) ... ... 14.8 (1777) ... -0.1 (1901)^
28 Mar ... 12.6 (1822,1998.) .. -0.3 (1785) ... 12.6 (1822)^ .. -0.3 (1785)
29 Mar ... 13.4 (1813) ... -0.7 (1785) ... ... 13.4 (1813) ... -0.7 (1785)
30 Mar ... 15.1 (2017)..... 0.0 (1799) ... ... 15.2 (2017) ... 0.0 (1799)

31 Mar ... 14.3 (2021) ... -0.8 (1799) ... ... 14.4 (2021) ... -0.8 (1799)


01 Apr ... 13.3 (1995) ... -0.2 (1917) ... ... 13.4 (1995) ... 0.0 (1799, 1917)^
02 Apr ... 13.9 (1835) ... -0.5 (1917) ... ... 13.9 (1835) ... -0.4 (1917)^
03 Apr ... 15.0 (1926&1946) .. -0.5 (1799) ... 15.0 (1946)^ .. -0.5 (1799)^
04 Apr ... 15.6 (1946)..... 1.0 (1809&1830) .. 15.6 (1946) ... 1.0 (1809, 1830)
05 Apr ... 13.3 (1857) ..... 0.4 (1911) ... ... 13.2 (1857) ... 0.5 (1911)

06 Apr ... 15.1 (2011) ..... 0.8 (1911) ... ... 15.2 (2011) ... 0.8 (1911)
07 Apr ... 14.7 (1859) ..... 1.0 (1839) ... ... 14.5 (1859) ... 1.0 (1839)
08 Apr ... 13.0 (2020) ..... 2.4 (1780) ... ... 13.1 (2020) ... 2.4 (1780)
09 Apr ... 13.7 (2017) ..... 1.4 (1812) ... ... 13.8 (2017) ... 1.4 (1812)
10 Apr ... 14.1 (2020) ..... 0.5 (1837) ... ... 14.1 (2020) ... 0.5 (1837)

11 Apr ... 16.0 (1869) ..... 1.3 (1978) ... ... 15.9 (1869) ... 1.3 (1978)
12 Apr ... 14.4 (1939) ..... 1.1 (1879) ... ... 14.5 (1939) ... 1.1 (1879)
13 Apr ... 14.6 (1792) ..... 1.1 (1816) ... ... 14.6 (1792) ... 1.1 (1816)
14 Apr ... 16.1 (1869) ..... 0.5 (1966) ... ... 15.9 (1869) ... 0.5 (1966)
15 Apr ... 16.3 (1945) ..... 1.4 (1966) ... ... 16.3 (1945) ... 1.5 (1966)^

16 Apr ... 17.0 (1945) ..... 2.0 (1892) ... ... 17.1 (1945) ... 2.2 (1837, 1892)^
17 Apr ... 14.9 (1865) ..... 2.1 (1793&1812) .. 14.8 (1865,2003)^ .. 2.1 (1793,1812)
18 Apr ... 17.0 (2018.)..... 1.7 (1807) ... ... 17.0 (2018.) ... 1.7 (1807)
19 Apr ... 17.6 (2018.) ... -0.2 (1772) ... ... 17.7 (2018.) ...-0.2 (1772)
20 Apr ... 16.6 (1893) ..... 2.3 (1849) ... ... 16.7 (1893) ... 2.3 (1849)

21 Apr ... 16.1 (1893) ..... 2.4 (1936) ... ... 15.8 (1893) ... 2.4 (1936)
22 Apr ... 15.4 (2011) ..... 3.4 (1778.) ... ... 15.4 (2011) ... 3.4 (1778.)
23 Apr ... 15.9 (1874) ..... 2.6 (1908.) ... ... 15.9 (2011)^ .. 2.5 (1908.)
24 Apr ... 15.3 (2007) ..... 0.5 (1908.) ... ... 15.4 (2007) ... 0.6 (1908.)
25 Apr ... 15.9 (1821) ..... 1.8 (1908.) ... ... 15.9 (1821) ... 1.8 (1908.)

26 Apr ... 16.1 (1928) ..... 3.3 (1981) ... ... 15.9 (1821)^ .. 3.4 (1981)
27 Apr ... 16.5 (1866) ..... 2.7 (1919) ... ... 16.3 (1866) ... 2.8 (1919)
28 Apr ... 16.9 (1775) ..... 3.0 (1826) ... ... 16.9 (1775) ... 3.0 (1826)
29 Apr ... 19.7 (1775) ..... 0.7 (1856) ... ... 19.7 (1775) ... 0.7 (1856)
30 Apr ... 17.4 (1775) ..... 2.6 (1945) ... ... 17.4 (1775) ... 2.7 (1945)

_______________________________________

^ Notes: 

 4 Mar 1909 loses record to 1845, 1909 incr -2.9 to -1.9, 1845 stayed at -2.8. 

 5 Mar 1909 loses tied record, incr -2.8 to -2.1 (1786 stayed -2.8)

 7 Mar 1875 loses record to 2014, as it decr from 10.9 to 10.7, 2014 incr 10.7 to 10.8.

14 Mar 2024 replaces 1805 (11.5) in v2.0. 

15 Mar 1845 gains tie with 1867, which was increased from -1.6 to -1.5 (1845 stayed at that value).

18 Mar 1853 retains sole record as 2018 which was -1.1 in legacy CET increased to -1.0.

21 Mar 1927,1931 tie added 2002 as third tie, when it increased from 11.6 to 11.7 (the others stayed unchanged). 

22 Mar 1927 gained record from 1903 which decreased from 12.6 to 12.0, while 1927 went from 12.3 to 12.2.

23 Mar 1886 new record high, the former value 11.4 was increased by 1.0 to 12.4; the formerly tied 1852, 1945 each stayed at 12.1).

23 Mar 1899 lost share of record when it was increased from -0.8 to -0.6, 1837 stayed at -0.8 to retain full record status.

26 Mar 1901 lost share of record when it was increased from -0.3 to -0.2, 1879 stayed at -0.3 to retain full record status.

27 Mar 1901 retained record but with the decrease to -0.1 from +0.1, that pushes back the first non-negative record to 30th March, and the first positive value to 4th of April.

28 Mar 1998 lost share of record with 1822, when its value was adjusted down from 12.6 to 12.5 (1822 stayed at 12.6). 

 1 Apr 1917 became tied with 1799 as its previous value of -0.2 was adjusted to 0.0 (which 1799 had before).

 2 Apr 1917 lost the status of tied record monthly low (-0.5) when it was adjusted to -0.4 (daily record retained).

 3 Apr 1926 lost share of record with 1946, when its value was adjusted down from 15.0 to 14.7 (1946 stayed at 15.0)

 3 Apr 1799 now sole owner of the April monthly record of -0.5 (formerly tied with 2 Apr 1917). 

15 Apr 1892 was also 1.5 in legacy (where 1966 was 1.4) but increased to 1.9 to stay out of the record tie. 

16 Apr 1892 fell back into a tie with 1837 when it was adjusted up from 2.0 to 2.2 (1837 stayed at 2.2). 

17 Apr 2003 gained a tie with 1865, as 1865 was adjusted down from 14.9 to 14.8 (2003 remained at 14.8).

23 Apr 1874 lost record to 2011. 1874 was adjusted down 14.9 to 14.7, 2011 went up from 14.8 to 14.9. 

26 Apr 1821 gained a record (15.9) when 1928 was adjusted down from 16.1 to 15.7. 

________________________________

also of interest, 31 Mar 1859, which had been lurking at -0.5, was adjusted up to -0.3. (record -0.8 1799)

and by staying at 0.5, 14 Apr 1966 kept 0.6 from 14 Apr 1816 out of the records. 

________________________________

NEXT POST AROUND LATE SAT 14th WILL DETAIL MAY-JUNE RECORD CHANGES. 

HOPE TO GET THE WHOLE YEAR REVIEWED BY MIDDLE OF NEXT WEEK. 

 

 

Edited March 16 by Roger J Smith

[Thundery wintry showers]

Here's an Excel file with the new CET monthly values, annual averages to 2 decimal places and the 30-year averages from 1961-1990 to 1991-2020.  The annual values may be slightly out because I'm guessing that the Met Office's values will be calculated from the raw monthly values rather than the rounded ones and therefore there will be some minor rounding errors.  The average for 1995 that I get is 10.44.

The 1961-1990 averages are mostly still the same as what I grew up with, but July is down from 16.1 to 16.0, October from 10.6 to 10.5, November from 6.5 to 6.4, and December from 4.7 to 4.5.

Hope this Excel file might help with your stats Roger.

CET20.xlsx

[Roger J Smith]

Thanks, I have my own excel files all updated now with v2.0, and have a table of daily comparisons for reference as I move through the annual records. 

Here's the play by play for December 2000 ... most days were adjusted down but there were some fairly large downward moves in the colder portion at the end of the month, 0.2 of the 0.5 adjustment happened in the last three days of the month: 

V2.0 ___ Adjustment from Legacy CET

 9.9 ____ -0.7

 9.4 ____ -0.2

 7.5 ____ -0.3

 9.3 ____ -0.2

11.3 ____ -0.2

 9.8 ____ -0.2

 9.0 ____ -0.3

 8.7 ____ -0.2

 8.7 ____ -0.2

 9.5 ____ -0.3

10.1 ____ -0.2

11.8 ____ -0.3

 8.5 ____ +0.4

 5.6 ____ -0.2

 3.8 ____ -0.2

 1.7 ____ -0.9

 1.9 ____ -0.2

 3.5 ____ -0.2

 5.6 ____ -0.3

 7.6 ____ +0.2

 5.5 ____ -0.2

 5.0 ____ -0.2

 3.4 ____ -0.3

 3.6 ____ -0.3

 2.7 ____ -0.2

 0.6 ____ -0.5

-0.1 ____ -1.0

-1.2 ____ -1.0

-4.0 ____ -2.1

-3.3 ____ -2.5

 0.3 ____ -1.4

 

[Weather-history]

Why have so many Decembers have gone down by a notch or two whilst January it has been the other way round?

Last 8 Decembers have gone down whilst 4 Januarys have gone up in that period have gone up?

[Roger J Smith]

It is clear from this analysis (attached excel file graph) that the months have been treated differently. This is an average of the changes made to each day, on average, from 1980 to 2022 inclusive. Feb and Aug have been warmed, Jan, Mar, Apr and May have seen very little change, also Sep, although some warming mostly in April, June has been cooled down slightly and Oct to Dec have been cooled more substantially. Given the parameters of the changes as explained, I am not sure why that would be the case. I will show for comparison what more recent segments of this 42.33 year interval look like in another post. 

Weather-history, this does not answer your question directly but it provides a clue. I can't imagine how we get this pattern unless there was a deliberate attempt to treat months differentially. It may be an availability of data question in different months. It seems likely that these differential treatments occurred with different frameworks for intervals and what we see here is an average of several different adjustment regimes, each with a monthly foundation (although not so strict that every day is exactly the same within a given month).

AVERAGE DAILY CHANGE (v2.0 minus legacy) in C deg 1980 to 2022

(average of 43 years 1 Jan to 30 Apr, exc 11 years 29 Feb; 42 years 1 May to 31 Dec

Edited May 14, 2022 by Roger J Smith

[Roger J Smith]

So here's an analysis of the same thing, confined to the past 10-11 years (1 Jan 2012 to 30 Apr 2022). It also shows monthly scale differentiation of the changes, although not always the same as the longer interval averages. 

AVERAGE DAILY CHANGE (v2.0 minus legacy) in C deg 2012 to 2022

(average of 11 years 1 Jan to 30 Apr, exc 3 years 29 Feb; 10 years 1 May to 31 Dec

 

 

Edited May 14, 2022 by Roger J Smith

[Earthshine]

Minimum CET for August had a fairly big increase from 13.3°C to 13.6°C, making it the second highest minimum CET August after 1997 with 14.0°C.  July 2018 maximum CET of 25.5°C now ahead of 1983 and only 0.1°C behind 2006.

[Roger J Smith]

Here is the next update to daily records covering May and June. The 1976 heat wave comes through (including first week of July not included here) with just the loss of two ties at the end of the heat wave (formerly 1923 and 1870 shared the last two records set; 1826 and 1852 had interrupted the otherwise unbroken streak and this continues to be the case, and then 2015 intervened on 1st July and that is also maintained. Perhaps the most notable change in this segment is the transfer from 3 June 1947 to 19 June 2005 of the warmest June daily mean (now 23.2 for 19 June 2005, was 23.0 for 3 June 1947). There are quite a few changes to record lows in this interval which may be of limited interest as most of the changes are from well back, but 1981 does gain a share of the 27 June minimum which it did not have before. Recent May record lows from 1979, 1984 and 1996 made it through unscathed, as did the three from early June 1991 (in fact one shed an earlier tie). 

 

LEGACY CET DAILY RECORDS with v2.0 changes noted 

... underlined are new ties, bold type show new records that have replaced older (or newer) ones

 

May-Jun daily records (Legacy) _____ May-Jun daily records (v2.0)

01 May ... 16.1 (1990, 2005) .. 4.2 (1866) ... 16.0 (1990, 2005) .. 4.2 (1945)^
02 May ... 16.4 (1966) .... 3.8 (1979) ... ... 16.4 (1966) ... 3.7 (1979)
03 May ... 17.7 (1990) .... 3.1 (1877) ... ... 17.6 (1990) ... 3.2 (1877)
04 May ... 18.0 (1834) .... 3.2 (1877) ... ... 18.0 (1834) ... 3.2 (1877)
05 May ... 16.7 (1800) .... 4.0 (1979) ... ... 16.7 (1800) ... 3.9 (1979)

06 May ... 18.8 (1867) .... 4.4 (1831) ... ... 18.6 (1867) ... 4.4 (1831)
07 May ... 16.9 (2018.) ... 4.1 (1879) ... ... 17.0 (2018.) ... 3.8 (1879)
08 May ... 17.8 (2016) .... 2.9 (1861) ... ... 17.7 (2016) ... 3.1 (1861)^
09 May ... 17.6 (1945&2016) .. 5.7 (1837) .. 17.6 (1945&2016) .. 5.1 (1910)^
10 May ... 18.2 (1959) .... 4.1 (1879) ... ... 18.2 (1959) ... 4.2 (1879)

11 May ... 18.6 (2008) .... 4.1 (1773) ... ... 18.7 (2008) ... 4.1 (1773)
12 May ... 18.8 (1945) .... 4.4 (1816) ... ... 18.8 (1945) ... 4.4 (1816)
13 May ... 17.4 (1959) .... 5.0 (1915) ... ... 17.4 (1959) ... 5.1 (1855)^ 
14 May ... 18.8 (1992) .... 3.9 (1839) ... ... 18.8 (1992) ... 3.9 (1839)
15 May ... 20.0 (1833) .... 4.3 (1839) ... ... 20.0 (1833) ... 4.3 (1839)

16 May ... 20.0 (1808) .... 5.2 (1996) ... ... 20.0 (1808) ... 5.2 (1996)
17 May ... 19.7 (1833) .... 3.6 (1935) ... ... 19.7 (1833) ... 3.6 (1935)
18 May ... 19.1 (1952) .... 4.1 (1872) ... ... 19.0 (1952) ... 4.2 (1872)
19 May ... 20.4 (1868) .... 5.2 (1872) ... ... 20.3 (1868) ... 5.3 (1872)
20 May ... 17.5 (1916) .... 5.5 (1907) ... ... 17.7 (1916) ... 5.8 (1894)^

21 May ... 18.8 (1916) .... 5.7 (1894) ... ... 18.8 (1918)^ .. 5.7 (1894)
22 May ... 19.5 (1918) .... 5.0 (1867) ... ... 19.6 (1918) ... 5.1 (1867)
23 May ... 19.5 (1922) .... 4.9 (1867) ... ... 19.5 (1922) ... 5.0 (1867)
24 May ... 18.8 (1953) .... 5.7 (1867) ... ... 18.8 (1953) ... 5.7 (1867)
25 May ... 21.0 (1953) .... 6.5 (1814) ... ... 20.9 (1953) ... 6.5 (1814)

26 May ... 18.7 (1784&2017) .. 4.6 (1821) .. 18.7 (1784&2017) .. 4.6 (1821)
27 May ... 19.0 (1788) .... 6.6 (1984) ... ... 19.0 (1788) ... 6.7 (1984)
28 May ... 20.6 (1847) .... 6.2 (1869) ... ... 20.6 (1847) ... 6.3 (1869)
29 May ... 21.2 (1780) .... 6.2 (1869) ... ... 21.2 (1870) ... 6.3 (1869)
30 May ... 21.0 (1944) .... 4.9 (1807) ... ... 21.0 (1944) ... 4.9 (1807)

31 May ... 20.5 (1947) .... 6.4 (1802) ... ... 20.5 (1947) ... 6.4 (1802)


01 Jun ... 20.9 (1781) .... 7.7 (1802&1962) ... 20.9 (1781&1947)^.. 7.7 (1802&1962)
02 Jun ... 22.3 (1947) .... 7.6 (1991) ... ... 22.3 (1947) ... 7.4 (1991)
03 Jun ... 23.0 (1947) .... 7.9 (1773) ... ... 22.9 (1947)^.. 7.9 (1773)
04 Jun ... 20.3 (1982) .... 8.0 (1871&1991) .. 20.2 (1804, 1982)^.. 8.0 (1991)^
05 Jun ... 21.3 (1982) .... 8.2 (1991) ... ... 21.2 (1982) ... 8.1 (1991)

06 Jun ... 22.5 (1950) .... 8.4 (1909) ... ... 22.4 (1950) ... 8.3 (1909)
07 Jun ... 21.6 (1846) .... 8.6 (1814) ... ... 21.6 (1846) ... 8.6 (1914)
08 Jun ... 20.4 (1940) .... 8.6 (1881&1914) .. 20.2 (1940) .. 8.2 (1881)^
09 Jun ... 20.9 (1970) .... 7.3 (1816) ... ... 20.9 (1970) ... 7.3 (1816)
10 Jun ... 21.5 (1970) .... 8.2 (1821) ... ... 21.5 (1970) ... 8.2 (1821)

11 Jun ... 21.0 (1970) .... 8.0 (1777) ... ... 21.0 (1970) ... 8.0 (1777)
12 Jun ... 20.8 (2006) .... 8.6 (1841) ... ... 21.7 (2023) ... 8.6 (1841)
13 Jun ... 20.5 (1818&1989) .. 8.5 (1901) ... 20.9 (2023)^ .. 8.6 (1801)^
14 Jun ... 19.4 (1814) .... 7.9 (1903) ... ... 19.4 (1814) ... 8.3 (1903)
15 Jun ... 22.9 (1858) .... 8.1 (1850) ... ... 22.7 (1858)^... 8.1 (1850)

16 Jun ... 20.7 (1858&1896) .. 9.6 (1869) ... 20.7 (1858&1896) .. 9.7 (1869)
17 Jun ... 21.4 (1917) .... 9.1 (1928) ... ... 21.3 (1917) ... 9.1 (1928)
18 Jun ... 21.2 (2005) .... 8.1 (1855) ... ... 22.2 (2005) ... 8.1 (1855)
19 Jun ... 22.1 (2005) .... 7.3 (1795) ... ... 23.2 (2005) ... 7.3 (1795)
20 Jun ... 21.7 (1846) .... 9.0 (1795&1964) .. 21.7 (1846) .. 9.0 (1795&1964)

21 Jun ... 22.7 (1817) .... 9.8 (1903) ... ... 22.7 (1817) ... 9.3 (1903)
22 Jun ... 22.3 (1941) .... 9.0 (1823) ... ... 22.3 (1941) ... 9.0 (1823)
23 Jun ... 21.8 (1935) .... 9.4 (1823) ... ... 21.8 (1935) ... 9.4 (1823)
24 Jun ... 22.0 (1935) .. 10.1 (1784) ... ... 22.1 (1935) ...10.1 (1784)
25 Jun ... 22.6 (2020) .... 8.7 (1835) ... ... 22.6 (2020) ... 8.7 (1835)

26 Jun ... 22.3 (1976) .... 9.7 (1835) ... ... 22.2 (1976) ... 9.7 (1835)
27 Jun ... 22.8 (1826) .. 10.2 (1862) ... ... 22.8 (1826) .. 10.3 (1835, 1862, 1981)^
28 Jun ... 22.6 (1976) .... 9.4 (1812) ... ... 22.5 (1976) ... 9.4 (1812)
29 Jun ... 22.4(1976) .... 9.7 (1839) ... .... 22.3 (1976) ... 9.7 (1839)
30 Jun ... 22.1 (1976) .... 9.1 (1839) ... ... 22.0 (1976) ... 9.1 (1839)

____________________________________

^ Notes:

 1 May 4.2 (1866) loses record to 4.2 (1945), previously they had been 4.2, 4.3, now reversed. 

 8 May 3.1 (1861) is still the monthly record low daily mean (was 2.9 in legacy) but retained it only because 3 May 1877 incr 3.1 to 3.2. 

 9 May 1910 (5.2) gained a record with a decrease from 5.8 in legacy CET, while 1837 stayed at 5.7 and lost its record. 

13 May 1855 (5.1) gained a record by remaining at 5.1 while 1915 increased from 5.0 to 5.4.

20 May 1894 (5.8) gained a record with a decrease from 6.0 while 1907 went up from 5.5 to 6.2, losing its record. 

21 May 1916 (18.5) lost a record with a decrease from 18.8, while 1918 gained the record by gaining 0.2 from 18.6 to 18.8.

 1 June 1947 (20.9) moved into a tie with 1781 with an increase from 20.8 (1781 unchanged). 

 3 June 1947 (22.9) no longer warmest June daily mean (was 23.0) as 19 June 2005 boosted 1.0 from 22.2 to 23.2. 

 4 June 1804 (20.2) gained a tie with 1982 when 1982 decr from 20.3 to 20.2 (1804 unchanged). 

 4 June 1991 (7.8) now sole owner of record low as 1871 adjusted from 8.0 to 8.1, while 1991 decr 8.0 to 7.8. 

 8 June 1914 (8.3) moved out of a tie, it had a decrease from 8.6 but 1881 went even lower from 8.6 to 8.2. 

12 June 2023 (21.7) broke existing 20.8 (2006) in both legacy and v2.0. 

13 June 1989 (20.7) lost share of tie with 1818, decrease from 20.5 to 20.4 (1818 remains 20.5). see next entry

13 June 2023 (20.9) broke existing 20.5 (1818) in v2.0 and (tie 1818, 1989) in legacy.

13 June 1801 (8.6) new record low, as previous 8.5 (1901) increased to 8.8. 

15 June 1858 (22.7) is a recent revision in v2.0.1.0 (was 22.8 in v2.0). 

19 June 2005 (23.2) boosted 1.0 from 22.2 to 23.2, now warmest daily mean in June (see note 3 June 1947). 

27 June 1862 (10.3) now tied by both 1835 (was 10.3) and 1981 (was 10.4), as 1862 was adjusted up from 10.2.  

--------------------

(comments on near misses and notables)

1 May 1958 was 15.9 and remains 15.9, closer to the 1990-2005 tie but still not a record. 

 7 May 2008 now 16.9 (was 16.8), moving up 0.1 as did 2018 with the new record now 17.0.

24 May 1814 (5.8) remains 0.1 above 1867 record, a tie would have resulted if the same corrections to 22-23 May 1867 had applied to 24th.

25 and 26 May 2012 unchanged at 18.3, 18.4. (24th up from 17.9 to 18.0). 

29 May 1944 (21.1) unchanged, and remains 0.1 behind 21.2 same date 1780, which retains warmest value for May.

30 May 1855 (5.8) also unchanged, held out of the records by exceptional 4.9 (1807). 

31 May 1975 (7.1) unchanged (was not a record before but very cold "recent" late May reading.

 7 June 1985 (8.7) moved 0.1 closer to 1814 record (8.6) with adjustment from 8.8 to 8.7. 

 8 June 1970 (20.1) edged within 0.1 of 1940 record due to its decrease from 20.4 to 20.2. Next three days remain 1970 records. 

19, 21 June 2017 are now 21.7, 21.8 (were 21.7, 21.9). (not records)

27 June 1878 decr from 22.7 to 22.4 (was closer to 1826 record before, now tied with 1976). 

27 June 2011 decr from 22.0 to 21.9. 

-------------------------------------------

NEXT SEGMENT for JULY-AUGUST should appear later Sunday evening or Monday morning, will be interesting as it contains all those major summer heat records.

Edited January 23 by Roger J Smith

[Earthshine]

Just noticed the February 2019 maximum CET was increased to 11.5°C which is a massive 4.9°C above the 1961-1990 average.  In fact the maximum CET anomaly for that month is comparable to the extreme months of July 2006 (+5.2°C) and December 2015 (+5.1°C).

[Roger J Smith]

There were only a few changes to July and August records, the most significant development was that the three warmest days came out in a new order with 29 July 1948 (25.1) now third behind top finisher 25 July 2019 (now 25.3), and 12 Aug 2020 (25.2). Almost all of the familiar daily records survived with minor changes. 1893 lost a record high to 1947 and 1773 lost a tie with 1997 (both changes in August) with 1955 adding a tie to its two record highs later in August. Also 1804 dropped out of a tie with 2008 on the 30th Aug and 2005 took over 31 Aug from 1906. Cold daily records are mostly from before 1850 when numbers remain unchanged, but 1961, 1965 and 1993 managed to hold on without any of those records being adjusted up (10th July 1993 went down 0.1 to 11.1, as did several following days that were not daily records but very cool). The most significant change in cold records is probably the loss of 9.5 on 16 Aug 1888 to 9.9 in 1810, due to an unusually large adjustment upwards of 1.1 deg to the 1888 value. That was previously the first daily mean at 9.5 or lower in the late summer (8.7 in July 1836 remains a record). 

*Note: July 18, 19 provide the first examples of new records in v2.0 where the legacy values cannot be updated (as they were discontinued as of 1 May 2022). The v2.0 values for the former records were 23.3 (1825) and 24.6 (2006).

14 Aug at 23.6 becomes the third day to break a v2.0 record, 21.7 from 1911.

 

LEGACY CET DAILY RECORDS with v2.0 changes noted 

... underlined are new ties, bold type show new records that have replaced older (or newer) ones

 

Jul-Aug daily records (Legacy) _____ Jul-Aug daily records (v2.0)

01 Jul ... 24.6 (2015) ... 10.4 (1773) ... ... 24.7 (2015) ... 10.4 (1773)
02 Jul ... 22.8 (1976) ... 11.3 (1821) ... ... 22.8 (1976) ... 11.3 (1821)
03 Jul ... 24.6 (1976) ... 10.1 (1907) ... ... 24.4 (1976) ... 10.1 (1907)
04 Jul ... 24.7 (1976) ... 10.0 (1965) ... ... 24.5 (1976) ... 10.0 (1965)
05 Jul ... 24.0 (1852) ... 10.7 (1920) ... ... 24.0 (1852) ... 11.2 (1816&1920)

06 Jul ... 23.3 (1976) ... 11.3 (1877) ... ... 23.2 (1976) ... 11.3 (1877)
07 Jul ... 22.6 (1923&1976) .. 11.1 (1877) ...  22.7 (1923)^ ... 11.1 (1877)
08 Jul ... 21.4 (1870&1976) .. 10.6 (1823) ... 21.4 (1870)^ ... 10.6 (1823)
09 Jul ... 21.6 (1921) ... 11.0 (1856) ... ... 21.6 (1921) ... 11.0 (1856)
10 Jul ... 22.1 (1921) ... 11.2 (1993) ... ... 22.2 (1921) ... 11.1 (1993)

11 Jul ... 22.6 (1783) ..... 9.4 (1888) ... ... 22.6 (1783) .... 9.0 (1888)
12 Jul ... 23.7 (1923) ... 11.0 (1840) ... ... 23.6 (1923) ... 11.0 (1840)
13 Jul ... 24.5 (1808) ... 10.2 (1840) ... ... 24.5 (1808) ... 10.2 (1840)
14 Jul ... 24.4 (1808) ... 11.7 (1961) ... ... 24.4 (1808) ... 11.7 (1961)
15 Jul ... 23.7 (1825) ... 11.5 (1883) ... ... 23.7 (1825) ... 11.4 (1883)

16 Jul ... 22.7 (2003) ... 11.5 (1823) ... ... 22.5 (2003) ... 11.5 (1823)
17 Jul ... 22.3 (1834) ... 11.0 (1892) ... ... 22.3 (1834) ... 11.2 (1892)
18 Jul ... 23.3 (1825)*... 10.1 (1863) ... ... 24.4 (2022) ... 10.1 (1863)
19 Jul ... 24.5 (2006)*... 10.6 (1892) ... ... 28.1 (2022) ... 10.6 (1892)
20 Jul ... 23.5 (2016) ..... 8.7 (1836) ... ... 23.6 (2016) .... 8.7 (1836)

21 Jul ... 23.1 (1868) ... 11.3 (1902) ... ... 23.1 (1868) ... 11.3 (1902)
22 Jul ... 23.2 (1868) ... 11.5 (1902) ... ... 23.1 (1868) ... 11.4 (1902)
23 Jul ... 22.5 (2019) ... 10.1 (1843) ... ... 22.6 (2019) ... 10.1 (1843)
24 Jul ... 23.9 (1818) ... 11.1 (1843) ... ... 23.9 (1818) ... 11.1 (1843)
25 Jul ... 25.2 (2019) ... 10.9 (1920) ... ... 25.3 (2019)^ .. 11.2 (1920)

26 Jul ... 23.2 (2006) ... 11.0 (1884) ... ... 23.3 (2006) ... 11.0 (1884)
27 Jul ... 22.5 (2018.) ...10.6 (1867) ... ... 22.7 (2018.) ... 10.6 (1867)
28 Jul ... 23.7 (1948) ... 11.8 (1886&1891) ..23.7 (1948) ... 11.6 (1886)^  
29 Jul ... 25.2 (1948) ... 11.0 (1816) ... ... 25.1 (1948) ... 11.0 (1816)
30 Jul ... 23.1 (1948) ... 10.6 (1786) ... ... 23.1 (1948) ... 10.6 (1786)

31 Jul ... 23.7 (2020)..... 10.9 (1841) ... ... 23.8 (2020) ... 10.9 (1841)


01 Aug ... 24.9 (1995) ... 11.9 (1888) ... ... 24.8 (1995) ... 11.9 (1888&1907)^
02 Aug ... 24.6 (1995) ... 11.6 (1822) ... ... 24.6 (1995) ... 10.9 (1912)^
03 Aug ... 24.4 (1990) ... 10.5 (1912) ... ... 24.4 (1990) ... 10.8 (1912)
04 Aug ... 23.4 (1975) ... 11.3 (1812) ... ... 23.4 (1975) ... 11.3 (1812)
05 Aug ... 23.1 (2003) ... 11.3 (1812) ... ... 23.1 (2003) ... 11.3 (1812)

06 Aug ... 22.5 (2003) ... 11.2 (1823&1860) ..22.5 (2003) ... 11.2 (1860) 
07 Aug ... 22.8 (1975) ... 11.6 (1898) ... ... 22.8 (1975) ... 11.6 (1898)
08 Aug ... 23.7 (1975) ... 11.5 (1823) ... ... 23.8 (1975) ... 11.5 (1823)
09 Aug ... 23.9 (2003) ... 11.0 (1931) ... ... 23.9 (2003) ... 10.9 (1931)
10 Aug ... 22.5 (1773&1997) .. 10.8 (1892) ...22.6 (1997)^.. 11.0 (1892)

11 Aug ... 24.0 (2020) ... 10.8 (1902) ... ... 24.2 (2020) ... 10.6 (1902)
12 Aug ... 25.1 (2020) ... 10.5 (1912) ... ... 25.2 (2020) ... 10.3 (1912)
13 Aug ... 23.6 (1911) ... 10.5 (1881) ... ... 23.9 (1911) ... 10.6 (1881)
14 Aug ... 21.3 (1911) ... 10.8 (1912) ... ... 23.6 (2022) ... 11.0 (1912)
15 Aug ... 22.1 (1893) ... 10.3 (1829) ... ... 21.7 (1893) ... 10.3 (1829)

16 Aug ... 21.6 (1947) ..... 9.5 (1888) ... ... 21.6 (1947) .... 9.9 (1810)^
17 Aug ... 22.4 (1876) ... 10.9 (1888) ... ... 22.4 (1876) ... 10.9 (1888)
18 Aug ... 22.6 (1893) ... 10.3 (1830) ... ... 22.1 (1947)^.. 10.3 (1830)
19 Aug ... 22.8 (1932) ... 10.4 (1839) ... ... 22.8 (1932) ... 10.4 (1839)
20 Aug ... 21.9 (1995) ... 10.5 (1920) ... ... 21.9 (1995) ... 10.2 (1920)

21 Aug ... 21.6 (1984) ..... 9.8 (1850) ... ... 21.6 (1984) .... 9.8 (1850)
22 Aug ... 22.1 (1955) ... 10.4 (1817) ... ... 22.1 (1955) ... 10.4 (1817)
23 Aug ... 22.1 (1955) ... 10.3 (1877) ... ... 22.1 (1955) ... 10.4 (1877)
24 Aug ... 21.5 (1990) ..... 9.1 (1864) ... ... 21.4 (1955&1990)^.. 9.1 (1864)
25 Aug ... 21.7 (2019) .. 10.5 (1787,1843&64) .. 21.8 (2019) .. 10.5 (1787,1843&64)

26 Aug ... 20.6 (1869) .... 8.8 (1864) ... ... 20.6 (1869) .... 8.8 (1864)
27 Aug ... 22.8 (1930) ... 11.0 (1885&1890) .. 23.1 (1930) ... 11.0 (1785&1896)^ 
28 Aug ... 23.0 (1942) ... 10.5 (1919) ... ... 23.0 (1942) ... 10.1 (1912)^
29 Aug ... 22.6 (1930) ....10.1 (1812) ... ... 22.2 (1930) .... 10.1 (1812)
30 Aug ... 19.8 (1804&2008) ... 9.5 (1890) ... 19.9 (2008)^.. 9.6 (1890)

31 Aug ... 21.3 (1906) ..... 9.2 (1833) .., ... 21.3 (2005)^... 9.2 (1833)
 _________________________________________________

^ Notes:

 5 July ... 1816 gained share with 1920 when 1920 incr 0.5 from 10.7 to 11.2 (1816 remained 11.2). 

 7 July ... 1976 lost share of tie with 1923, decr 22.6 to 22.4, while 1923 incr 22.6 to 22.7.

 8 July ... 1976 lost share of tie with 1870, decr 21.4 to 21.2, while 1870 remained 21.4.

* 18 and 19 July __ no updated legacy CET values (series discontinued) 19th highest of data set for v2.0

... the value shown for 19th was 24.6 in CET v2.0 before being broken in 2022. 

25 July ... 2019 now warmest day of the data set, incr 0.1 from 25.2 (while 1948 29 July went down 0.1 to 25.1).

28 July ... 1886 gained sole record with decr from 11.8 to 11.6 while 1891 incr 11.8 to 12.0.

29 July ... 1948 (25.1) lost share of warmest day all-time, decr 25.2 to 25.1, while 25 July 2019 incr 25.2 to 25.3.

 1 Aug ... 1907 (11.9) decr 0.1 from 12.0 (legacy CET), gained share of tied record with 1888 (unchanged).

 2 Aug ... 1912 (10.9) gains record with 0.8 decr from 11.7, 1822 loses record as it remains 11.6. 

 6 Aug ... 1860 (11.1) gains sole record with 0.1 decr from 11.2, while 1823 loses share as it remains 11.1.

10 Aug ... 1773 lost share of tie with 1997, when 1997 incr 22.5 to 22.6; 1773 remained 22.5.

14 Aug ... v2.0 record was 21.7 in 1911 broken by 23.6 in 2022. 

16 Aug ... 1810 gained record (9.9) when 1888 incr by 1.1 from 9.5 to 10.6.

18 Aug ... 1893 lost record when 22.6 decr to 22.0, 1947 remained 22.1 for the new record.

24 Aug ... 1955 gained tie with 1990 when 1990 decr 21.5 to 21.4, 1955 remained 21.4. 

27 Aug ... 1785, 1896 (11.1) new tied pair replace 1885, 1890 which both increased, to 11.6 and 11.2.

28 Aug ... 1912 gains record with decr of 0.7 from 10.8 to 10.1; 1919 went from 10.5 to 10.4. 

30 Aug ... 1804 lost share of tie with 2008 which incr 0.1 from 19.8 to 19.9 (1804 remained 19.8).

31 Aug ... 2005 gains record with boost from 20.9 to 21.3, while 1906 loses record with decr from 21.3 to 20.8.

_______________________

Record cold near misses

1813 4 July remains 10.4, record was 10.1 now 9.9 (1907).

1838 22 July remains 11.6.

1812 23 July remains 10.7.

1841 12 Aug remains 10.7.

1845 21 Aug remains 10.2. 1986 21 Aug remains 11.0.

1813 23 Aug remains 10.6

 

Non-record hot days with changes (if any)

 6 July ... 1957 remains 22.3

12 July ... 1983 remains 22.6

13 July ... 1923 remains 24.0, 1983 down 0.1 from 22.7 to 22.6, 1926 up 0.1 to 22.0

14 July .,. 1926 up 0.2 from 22.1 to 22.3.

16 July ... 1983 22.4 down 0.1 from 22.5 (legacy CET) which is now record (2003).

19 July ... 2016 up 0.1 to 23.1.

20 July 1878 ... down 1.1 from 22.9 to 21.8, 1900 up 0.3 to 22.3

21 July 1989 ... 22.6 down 0.1 from 22.7 (legacy CET).

22 July 1989 ... 23.0 down 0.1 from 23.1 (legacy CET).

22 July 2021 ... up 0.1 from 22.2 to 22.3, and 2013 up 0.1 to 21.7

23 July 1989 ... 22.3 down 0.1 from 22.4 (legacy CET).

24 July 2019 ... up 0.1 from 23.1 to 23.2.

29 July 1911 _ now 23.2 from 23.4 (legacy CET)

31 July 1943, 1995 _ now tied 23.3, both were 23.4 in legacy CET.

 1 Aug 2013 ... 22.8, up 0.1 from 22.7 (legacy CET)

 2 Aug 1990 ... 23.8, down 0.1 from 23.9 (legacy CET).

 5 Aug 1868 ... 22.5 (no change)

11 Aug 1997 _ 22.6 (no change)

19 Aug 1997 _ 22.2 up 0.1 from 22.1 (legacy CET) and 1995 down 22.1 to 22.0.

28 Aug 1930 ... now 22.3 from 22.4 (legacy CET).

 

Edited August 16, 2022 by Roger J Smith

[Roger J Smith]

The changes in records for September and October follow. September has a new warmest day, 5 Sep 1949 (unchanged at 22.4) took over when 2 Sep 1906 was decreased by 0.3 from 22.6 to 22.3. Note _ new Sep max 23.3 on 7 Sep 2023 replaces both. 

The October monthly record high continues to be 1985 (1st) at 20.1, it was reduced by 0.1 but so was the previous 20.1 on 1st Oct 2011, so no change there. Following the new record on 31 Aug for 2005, three more are added in this segment. Increases also threatened two other records (in late October 1888) where 2005 is now quite a bit closer but still short of those records. There were actually two examples of a recent record (2006 and 2021) being replaced by an older record from the 1890s which they had recently replaced in the legacy CET, due to combinations of recent decreases or earlier increases. This had seldom been the case earlier in the year working through these segments.

Changes to the cold records are relatively minor and both monthly extremes are untouched (one because it was in 1824 before changes began, the other in Oct 1895 could have changed but did not, at 0.3). Most other well known cold records remain intact. A few have shifted around slightly but here again, most of the records are from the 19th century so changes are going to be limited. A recent very cold reading (29 Oct 2008) was reduced from 1.6 to 1.4. 

 

LEGACY CET DAILY RECORDS with v2.0 changes noted 

... underlined are new ties, bold type show new records that have replaced older (or newer) ones

 

Sep-Oct daily records (Legacy) _____ Sep-Oct daily records (v2.0)

01 Sep ... 21.8 (1780&1906) .. 7.1 (1816) ... 22.0 (1906)^.. 7.1 (1816)
02 Sep ... 22.6 (1906) .... 7.6 (1816) ... ... 22.3 (1906)^ .. 7.6 (1816)
03 Sep ... 20.2 (1880) .... 8.2 (1816&1908) .. 19.8 (1880) .. 8.2 (1816)^
04 Sep ... 20.7 (1880) .... 7.7 (1841) ... ... 20.6 (2005)^ .. 7.7 (1841)
05 Sep ... 22.4 (1949) .... 8.1 (1841) ... ... 22.4 (1949)^ .. 8.1 (1841)

06 Sep ... 20.8 (1898) .... 8.5 (1841) ... ... 21.1 (2023)^... 8.5 (1841)
07 Sep ... 21.1 (1868) .... 8.6 (1952) ... ... 23.3 (2023)^ ... 8.1 (1952)
08 Sep ... 21.4 (2021) .... 8.9 (1807&1931) .. 22.0 (2023)^ .. 8.8 (1931)^
09 Sep ... 19.8 (1898) .... 9.2 (1860&1912) .. 22.8 (2023)^ .. 9.0 (1912)^
10 Sep ... 19.2 (1865) .... 8.6 (1860) ... ... 21.6 (2023)^ .. .. 8.6 (1860)

11 Sep ... 20.3 (1999) .... 8.1 (1860) ... ... 20.2 (1999) ... 8.2 (1860)
12 Sep ... 20.4 (1945) .... 8.1 (1848) ... ... 20.3 (1945) ... 8.1 (1848)
13 Sep ... 20.7 (2016) .... 6.7 (1807) ... ... 20.7 (2016) ... 6.7 (1807)
14 Sep ... 21.3 (2016) .... 6.7 (1807) ... ... 21.3 (2016) ... 6.7 (1807)
15 Sep ... 20.1 (2020) .... 7.9 (1986) ... ... 20.1 (2020) ... 7.8 (1986)

16 Sep ... 19.6 (1961) .... 8.1 (1807) ... ... 19.6 (1961) ... 8.1 (1807&1903)^
17 Sep ... 20.4 (1898) .... 8.1 (1807) ... ... 20.1 (1898) ... 8.1 (1807)
18 Sep ... 19.7 (1926) .... 6.9 (1807) ... ... 19.8 (1926) ... 6.9 (1807)
19 Sep ... 20.9 (1926) .... 7.4 (1952) ... ... 20.9 (1926) ... 7.3 (1952)
20 Sep ... 18.4 (1947) .... 6.8 (1919) ... ... 18.4 (1947) ... 6.9 (1919)

21 Sep ... 21.4 (2006) .... 6.5 (1872) ... ... 21.4 (2006) ... 6.7 (1836&1872)^
22 Sep ... 18.7 (1956) .... 6.3 (1872) ... ... 18.7 (1956) ... 6.6 (1872)
23 Sep ... 18.3 (1956) .... 6.0 (1773) ... ... 18.3 (1956) ... 6.0 (1773)
24 Sep ... 18.3 (2006) .... 6.7 (1872) ... ... 18.5 (1895)^ .. 6.9 (1872)
25 Sep ... 19.4 (1895) .... 7.4 (1812) ... ... 19.2 (1895) ... 7.4 (1812)

26 Sep ... 18.4 (1895) .... 6.0 (1885) ... ... 18.4 (1895) ... 6.0 (1885)
27 Sep ... 19.0 (1895) .... 6.1 (1824&1885) .. 19.7 (1895) .. 6.0 (1885)^
28 Sep ... 18.9 (2011) .... 4.9 (1824) ... ... 18.9 (2011) ... 4.9 (1824)
29 Sep ... 19.7 (2011) .... 5.5 (1918) ... ... 19.7 (2011) ... 5.6 (1918)
30 Sep ... 20.0 (2011) .... 6.3 (1808) ... ... 20.0 (2011) ... 6.3 (1808)


01 Oct ... 20.2 (1985) .... 6.1 (1808&1888) .. 20.1 (1985)^ .. 6.1 (1808&1888)
02 Oct ... 17.9 (2011) .... 3.6 (1817) ... ... 17.9 (1959&2011)^ .. 3.6 (1817&1888)^
03 Oct ... 19.8 (2011) .... 4.7 (1817) ... ... 19.8 (2011) ... 4.7 (1817)
04 Oct ... 17.7 (1959) .... 5.1 (1912) ... ... 17.8 (1886)^.. 5.0 (1880)^
05 Oct ... 17.9 (1886) .... 4.6 (1888) ... ... 18.1 (1921)^.. 4.6 (1888)

06 Oct ... 19.0 (1921) .... 4.1 (1888) ... ... 18.9 (1921) ... 4.1 (1888)
07 Oct ... 16.9 (1921) .... 3.5 (1829) ... ... 17.5 (2023)^.. 3.5 (1829)
08 Oct ... 17.7 (1995) .... 4.1 (1829) ... ... 17.5 (1995) ... 4.1 (1829)
09 Oct ... 17.5 (1995) .... 3.3 (1852) ... ... 17.3 (1995) ... 3.3 (1852)
10 Oct ... 17.8 (1921) .... 3.5 (1814) ... ... 17.8 (1921) ... 3.5 (1814)

11 Oct ... 17.6 (1978) .... 3.9 (1860) ... ... 17.7 (2005)^.. 4.0 (1860)
12 Oct ... 16.5 (1978) .... 3.2 (1887) ... ... 16.3 (1978) ... 3.0 (1887)
13 Oct ... 18.5 (2018.).... 2.2 (1838) ... ... 18.4 (2018.) .. 2.2 (1838)
14 Oct ... 17.2 (2017) .... 3.1 (1838) ... ... 17.1 (2017) ... 3.1 (1838)
15 Oct ... 15.7 (1930) .... 2.5 (1843) ... ... 15.8 (1930) ... 2.5 (1843)

16 Oct ... 16.4 (2017) .... 1.8 (1843) ... ... 16.3 (2017) ... 1.8 (1843)
17 Oct ... 15.6 (1897) .... 2.5 (1824) ... ... 15.5 (1897) ... 2.5 (1824)
18 Oct ... 16.7 (2014) .... 2.4 (1843) ... ... 16.5 (2014) ... 2.4 (1843)

19 Oct ... 16.3 (1921) .... 1.5 (1813) ... ... 16.0 (1921) ... 1.5 (1813)
20 Oct ... 14.9 (1795) .... 2.1 (1842) ... ... 14.9 (1795) ... 2.1 (1842)

21 Oct ... 15.2 (1977) .... 1.2 (1842) ... ... 15.1 (1826)^.. 1.2 (1842)
22 Oct ... 16.2 (1906) .... 2.5 (1931) ... ... 16.1 (1906) ... 2.5 (1931)
23 Oct ... 14.4 (1998)*.... 0.9 (1859) ... ... 14.8 (2022)*... 1.0 (1859)
24 Oct ... 14.3 (2009) .... 0.6 (1859) ... ... 14.2 (2009) ... 0.7 (1859)
25 Oct ..14.0 (1978&2013) . 2.0 (1784) .. 13.9 (2013)^.. 2.0 (1784)

26 Oct ... 14.7 (1927) .... 1.5 (1785) ... ... 15.0 (2022)*... 1.2 (1895)^
27 Oct ... 16.7 (1888) .... 1.4 (1869) ... ... 16.6 (1888) ... 1.6 (1778&1869)^
28 Oct ... 15.6 (1888) .... 0.9 (1895) ... ... 15.4 (1888,2022) ... 1.2 (1895)
29 Oct ... 14.0 (1772&1984) .. 0.3 (1895) ... 14.9 (2022)* ... 0.3 (1895)
30 Oct ... 15.5 (2005) .... 0.7 (1836) ... ... 15.5 (2005) ... 0.7 (1836)

31 Oct ... 16.9 (2014) .... 0.7 (1836) ... ... 16.7 (2014) ... 0.7 (1836)

_______________________________

^ Notes: 

 1 Sep _ 1780 loses tie as 1906 incr 21.8 to 22.0 (1780 remains 21.8).

 2 Sep _ 1906 (22.3) no longer warmest Sep mean daily, replaced by 5 Sep 1949 (22.4)

 3 Sep _ 1908 (8.3) loses tie with 1816, incr 8.2 to 8.3. (1816 remains 8.2).

 4 Sep _ 2005 gains record (incr 20.4 to 20.6) while 1880 loses record (decr 20.7 to 20.1).

 5 Sep _ 1949 gains monthly maximum (see note 2 Sep) replaced 7 Sep 2023 

 6 Sep _ 2023 replaced v2.0 record 20.9 (1898)

 7 Sep _ 2023 replaced v2.0 record 20.9 (1868) and is a new max for September

 8 Sep _ 1898 regained record with incr 21.3 to 21.6, 2021 (which had replaced it in legacy CET) held at 21.4. These now replaced by 22.0 (2023).

 8 Sep _ 1931 takes sole possession of previous tie with 1807 with decr from 8.9 to 8.8 (1807 remains 8.9).

 9 Sep _ 1898 tied with 1781 after decr from 19.8 to 19.5 (1781 unchanged at 19.5). These now replaced by 22.8 (2023).

 9 Sep _ 1860 lost share of tie with 1912 as 1912 decr 9.2 to 9.0, 1860 remains 9.2. 

10 Sep _ 2011 gained share of tie with 1865, which decreased from 19.2 to 19.1 (2011 unchanged at 19.1). These now replaced by 21.6 (2023).

16 Sep _ 1903 gains share of tie with 1807, as 1903 decreased from 8.3 to 8.1 (1807 unchanged at 8.1).

24 Sep _ 2006 loses record to 1895 which incr from 18.0 to 18.5 (2006 unchanged at 18.3).

27 Sep _ 1824 loses share of tied record as 1885 decr from 6.1 to 6.0 (1824 unchanged at 6.1). 

 1 Oct _ 1985 retains monthly maximum (now 20.1, was 20.2) as 2011 Oct 1 also drops 0.1 (20.1 to 20.0).

 2 Oct _ 1959 gains tie with 2011 incr 17.6 to 17.7 (2011 unchanged at 17.7).

 2 Oct _ 1888 gains tie with 1817 with decr 4.0 to 3.6 (1817 unchanged at 3.6).

 4 Oct _ 1886 gains a record with incr 17.6 to 17.8 (1959 unchanged at 17.7).

 5 Oct _ 1921 gains a record with incr 17.7 to 18.1 (1886 17.9 to 18.0 lost record).

 5 Oct _ 1880 gains a record with decr 5.3 to 5.0, 1912 loses (remains 5.1). 

 7 Oct _ 2023 replaced 1921 (16.8) in v2.0 records. 

21 Oct _ 1977 loses record with decr 15.2 to 15.0, 1826 gains record (remains at 15.1).

23 Oct _ 1998 v2.0 14.2 record was broken by 14.8 in 2022.

25 Oct _ 1978 loses share of tied record, decr 14.0 to 13.8, while 2013 decr 14.0 to 13.9.

26 Oct _ 2022 replaced 1927 (14.9) in v2.0 records.

26 Oct _ 1895 gains record with decr from 1.9 to 1.2, 1785 remains 1.5 and loses record.

27 Oct _ 1778 gains tie with 1869 which incr from 1.4 to 1.6 (1778 remains 1.6).

28 Oct _ 1888 v2.0 record 15.4 tied by 2022.

29 Oct _ 2005 gains another record with incr from 13.9 to 14.1, 1772 remains 14.0, 1984 decr 14.0 to 13.9.

_ _ this record broken by 14.9 in 2022. 

 

_____________________________

Other Notable non-record daily mean temps (other than those removed as noted)

 6 Sep 1952 _ 8.6 (no change)

 8 Sep 1909 _ 8.9 (from 9.0) _ would have tied 1807, 1931 if both unchanged (1931 now 8.8).

10 Sep 1836 _ 8.8 (no change)

15 Sep 1903 _ 8.1 (from 8.0 in CET legacy)

18 Sep 1952 _ 7.1 (from 7.0 in CET legacy)

20 Sep 1952 _ 7.6 (from 7.9 in CET legacy)

22 Sep 1948 _ 7.0 (from 6.9 in CET legacy)

23 Sep 1844 _ 6.6 (no change)

25 Sep 1860 _ 7.7 (from 7.6 in CET legacy)

26 Sep 1824 _ 6.4 (no change)

28 Sep 1778, 1809 _ both 5.7 (no change)

29 Sep 1908 _ 19.0 (was 19.2 in CET legacy)

30 Sep 1908 _ 19.5 (was 19.6 in CET legacy)

 1 Oct 1908 _ 18.1 (no change)

 7 Oct 1888 _ 4.7 (from 5.0 in CET legacy)

 8 Oct 1852 _ 4.6 (no change)

 9 Oct 1979 _ 17.1 (from 17.3 in CET legacy)

 9 Oct 1829 _ 3.8

11 Oct 1896 _ 4.3 (no change)

13 Oct 1990 _ 16.7 (from 16.8 in CET legacy)

14 Oct 1990 _ 15.9 (from 16.1 in CET legacy)

16 Oct 1993 _ 2.6 (was 2.7 in CET legacy), 1824 2.7 (no change)

17 Oct 1905 _ 2.8 (was 2.7 in CET legacy), 1778 2.9 (no change)

18 Oct 1954 _ 16.1 (from 16.0 in CET legacy)

19 Oct 1843 _ 1.7 (no change)

21 Oct 1859 _ 1.8 (was 1.7 in CET legacy)

22 Oct 1905 _ 2.6 (was 2.8 in CET legacy)

24 Oct 2017 _ 14.1 (from 14.2 in CET legacy)

24 Oct 1895 _ 1.4 (was 1.2 in CET legacy), 1926 _ 1.7 (was 1.6).

27 Oct 2005 _ 16.2 (was 15.9 in CET legacy)

28 Oct 2005 _ 15.2 (was 15.0 in CET legacy)

28 Oct 1836 _ 1.5 (no change)

29 Oct 1836 _ 0.7 (no change), 1873 1.2 (was 1.1), 2008 1.4 (was 1.6). 

30 Oct 1772 _ 14.3 (no change)

30 Oct 1813 _ 1.5 (no change)

31 Oct 1772 _ 14.5 (no change)

31 Oct 1881 _ 1.3 (was 1.5 in CET legacy)

 

 

Edited October 8, 2023 by Roger J Smith

[Roger J Smith]

Working on the last segment of the records (Nov-Dec) and found a real surprise, 24 Nov 1904 not only lost its place as coldest day, it isn't even the date record any more. By adjusting it up from -4.6 to -3.5, it allowed 1816 to sneak in from -3.6 (unchanged) as date record. 

Also with 23 Nov 1858 adjusted from -4.2 to -3.9, and 28 Nov 2010 not adjusted at all, the 2010 cold record is now the monthly low at -4.0. 

So while it wasn't recognized as such at the time, the 28th November 2010 was the coldest November daily mean. I haven't looked at the minima yet to see if the same thing happened there. (1858 is out of the equation there having no max or min before 1878). 

[Don]

On 13/05/2022 at 20:30, Thundery wintry showers said:

The big surprise for me was December 2000 going from 5.8 to 5.3.  I'd have expected a downward adjustment to that month, possibly to 5.6 or even 5.5, but the drop to 5.3 is such a large step that I'm wondering if there was a glitch.

Perhaps the depth of cold between Boxing Day and NYE had more of an impact on the CET?

[cheeky_monkey]

11 minutes ago, Roger J Smith said:

Working on the last segment of the records (Nov-Dec) and found a real surprise, 24 Nov 1904 not only lost its place as coldest day, it isn't even the date record any more. By adjusting it up from -4.6 to -3.5, it allowed 1816 to sneak in from -3.6 (unchanged) as date record. 

Also with 23 Nov 1858 adjusted from -4.2 to -3.9, and 28 Nov 2010 not adjusted at all, the 2010 cold record is now the monthly low at -4.0. 

So while it wasn't recognized as such at the time, the 28th November 2010 was the coldest November daily mean. I haven't looked at the minima yet to see if the same thing happened there. (1858 is out of the equation there having no max or min before 1878). 

i still don't understand or no one has explained how you can change temperature records from over a 100 years ago..based on what exactly??..what was exactly wrong with the temperature record for 24 Nov 1904? but the records were ok for 23 Nov 1904 or 25 Nov 1904?

[Roger J Smith]

My position is, I'm just reporting on the changes, not here to defend or (with any authority at least) explain them. But their rationale for the changes appear to be a mixture of several different things, an attempt to make the numbers for different years more comparable by studying the data and stations used with the idea of standardizing certain aspects of all that, it could involve different things like changes in exposure, maybe a few time of day issues that needed to be standardized, some kind of indication that a contributing station for part of the record had a bias, removing a station from the mix or adding one not used before, these are all some of the factors that might have been involved. I looked at that cold period in Nov 1904 and considerably different changes were made to a consecutive streak of cold days, some went up and some went down. Did you happen to read their document which is linked early on in this thread? I share the frustration to some extent because at the end of the day this cannot be a very objective process that would be easily understandable. Sometimes you can look at older weather data and spot things that are probably not done by the same standard as modern climate records, for example, in some older data sets that I have used in various studies, the 24-hour climate day was evidently different and sometimes the range of max/min for one day and the following day have no point of overlap (as they should do), indicating that the period for max is different than the period for min observations in the older data. That is sometimes corrected and it usually tends to drop the averages of the older data by about 0.2 C deg (because you're more likely to get colder minima by standardizing the day used). People have noticed that sort of thing in adjusted data sets and claimed it was data manipulation to make the past "look" colder but it was actually an attempt to measure the past by presently used standards. I don't know if any of this has any application to the CET because I am not that clear as to what climatological day principles they use, whether midnight to midnight or some other blend. In North American data the standard is local midnight to midnight but it wasn't always recorded that way before about 1940. 

 

[Roger J Smith]

Final instalment of the legacy vs Leggacy drama ... as noted in earlier post, 24 Nov 1904 and 23 Nov 1858 both passed by 28 Nov 2010 which is now November's coldest day for mean daily CET. The December cold record of -10.9 set in 1796 was in no danger and is unchanged. The two months' warmest days are as before, in 1938 and 2015. Last New Years Eve is now within 0.1 of the 2015 December maximum. I have noted plenty of "also rans" showing the degree to which the data base has sometimes been altered even away from the daily records. There are not many changes to daily record holders in these two months, apart from a few ties being separated or created. The 1904 case is most significant, not only did the old record lose its position as monthly minimum, it also lost the day to 1816 which was lurking in the zone of nil change. 

 

LEGACY CET DAILY RECORDS with v2.0 changes noted 

... underlined are new ties, bold type show new records that have replaced older (or newer) ones

 

Nov-Dec daily records (Legacy) _____ Nov-Dec daily records (v2.0)

01 Nov ... 13.5 (1894&1982) .. 1.5 (1934) ... 13.7 (1894)^ .. 1.1 (1926)^
02 Nov ... 14.3 (1821) ... 0.5 (1880) ... ... 14.3 (1821) ... 0.4 (1880)
03 Nov ... 15.0 (1996) ... 1.9 (1820) ... ... 14.9 (1996) ... 1.8 (1980)^
04 Nov ... 14.2 (1946) ... 0.8 (1845&1848) .. 14.2 (1946) .. 0.8 (1845&1848)
05 Nov ... 15.4 (1938) ... 0.8 (1801) ... ... 15.5 (1938) ... 0.8 (1801&1901)^

06 Nov ... 14.3 (2015) .... 0.6 (1868) ... ... 14.2 (2015) ... 0.7 (1868)
07 Nov ... 13.8 (2015) ... -0.6 (1791) ... ... 13.7 (2015) ...-0.6 (1791)
08 Nov ... 13.4 (1852) ... -1.2 (1812) ... ... 13.4 (1852) ...-1.2 (1812)
09 Nov ... 12.5 (1998.)... -0.5 (1921) ... ... 12.3 (1998.) .. +0.2 (1921)
10 Nov ... 13.4 (1977) .... 0.1 (1812) ... ... 13.2 (1977,2015)^.. 0.1 (1812)

11 Nov ... 13.9 (2015) .... 0.3 (1828) ... ... 14.3 (2022)*.... 0.3 (1828)
12 Nov ... 13.8 (1938&1947) ... -1.4 (1919) .. 13.8 (1938&1947) ... -1.5 (1919)
13 Nov ... 14.6 (1938) .. -1.1 (1862) ... ... 14.7 (1938) .. -0.9 (1862)
14 Nov ... 13.4 (1938) .. -1.1 (1925) ... ... 13.4 (1938) .. -1.0 (1925)
15 Nov ... 13.5 (1821) .. -2.1 (1965) ... ... 13.5 (1821) .. -2.1 (1965)

16 Nov ... 13.4 (1997) .. -2.9 (1901) ... ... 13.3 (1997) .. -2.3 (1901)
17 Nov ... 13.1 (1997) .. -2.0 (1841) ... ... 12.9 (1997) .. -2.0 (1841)
18 Nov ... 12.8 (2020) .. -1.6 (1887) ... ... 12.7 (2020) .. -1.3 (1798&1871)^
19 Nov ... 12.7 (1994) .. -2.1 (1815) ... ... 12.5 (1994&2003)^ .. -2.1 (1815)
20 Nov ... 12.8 (2009) .. -1.2 (1829) ... ... 12.7 (2009) .. -1.2 (1829)

21 Nov ... 13.7 (1947) .. -1.4 (1880) ... ... 13.7 (1947) .. -1.5 (1880)
22 Nov ... 14.4 (1947) .. -2.3 (1773) ... ... 14.4 (1947) .. -2.3 (1773)
23 Nov ... 13.3 (1947) .. -4.2 (1858) ... ... 13.3 (1947) .. -3.9 (1858)
24 Nov ... 12.7 (1980) .. -4.6 (1904) ... ... 12.5 (1980) .. -3.6 (1816)^
25 Nov ... 12.1 (1964) .. -1.5 (1923) ... ... 12.1 (1964) .. -1.9 (1923)

26 Nov ... 12.1 (1983) .. -1.7 (1904) ... ... 11.9 (1983) .. -2.1 (1904)
27 Nov ... 11.3 (1818) .. -2.6 (1915) ... ... 11.3 (1818) .. -2.7 (1890)^
28 Nov ... 12.0 (1828) .. -4.0 (2010) ... ... 12.0 (1828) .. -4.0 (2010)^
29 Nov ... 12.2 (1818) .. -2.6 (1801) ... ... 12.2 (1818) .. -2.6 (1801)
30 Nov ... 12.4 (2001) .. -1.7 (1973) ... ... 12.3 (2001) .. -1.6 (1796&1973)^


01 Dec ... 12.1 (1775) .. -3.0 (1947) ... ... 12.1 (1775) .. -3.0 (1947)
02 Dec ... 12.2 (1985) .. -4.7 (1796) ... ... 12.0 (1985) .. -4.7 (1796)
03 Dec ... 12.2 (1985) .. -4.0 (1879) ... ... 12.1 (1985)^.. -4.2 (1879)
04 Dec ... 12.1 (1888) .. -3.8 (1879&1925) .. 12.0 (1888) .. -3.6 (1879&1925)
05 Dec ... 12.6 (1898) .. -3.7 (1844) ... ... 12.7 (1898) .. -3.7 (1844)

06 Dec ... 12.3 (1898) .. -5.5 (1844) ... ... 12.1 (1898) .. -5.5 (1844)
07 Dec ... 12.3 (1856) .. -5.7 (1879) ... ... 12.1 (1856) .. -5.3 (1879)
08 Dec ... 12.1 (1856) .. -5.4 (1807) ... ... 12.0 (1856) .. -5.4 (1807)
09 Dec ... 11.8 (1934) .. -4.0 (1803) ... ... 11.7 (1934) .. -4.0 (1803)
10 Dec ... 10.9 (1997) .. -4.5 (1784) ... ... 10.7 (1856&1997)^ .. -4.5 (1784)

11 Dec ... 12.6 (1994) .. -6.7 (1784) ... ... 12.4 (1994) .. -6.7 (1784)
12 Dec ... 12.9 (1994) .. -8.5 (1981) ... ... 12.7 (1994) .. -8.7 (1981)
13 Dec ... 11.6 (1918) .. -6.5 (1981) ... ... 11.5 (1918) .. -6.7 (1981)
14 Dec ... 11.8 (1912) .. -5.3 (1878) ... ... 11.5 (2006)^.. -5.5 (1878)

15 Dec ... 11.2 (1985) .. -5.4 (1788) ... ... 11.1 (1985) .. -5.4 (1788)

16 Dec ... 11.4 (2015) .. -6.6 (1859) ... ... 11.4 (2015) .. -6.4 (1859)
17 Dec ... 12.5 (2015) .. -7.7 (1859) ... ... 12.5 (2015) .. -7.5 (1859)
18 Dec ... 12.5 (2015) .. -7.1 (1859) ... ... 12.5 (2015) .. -7.0 (1859)
19 Dec ... 13.1 (2015) .. -6.8 (2010) ... ... 13.0 (2015) .. -6.8 (2010)
20 Dec ... 11.1 (1828) .. -7.0 (2010) ... ... 11.1 (1828) .. -7.0 (2010)

21 Dec ... 11.4 (1971) .. -5.9 (2010) ... ... 11.4 (1971) .. -5.9 (2010)
22 Dec ... 11.6 (1991) .. -6.8 (1890) ... ... 11.5 (1991) .. -5.7 (1890)
23 Dec ... 11.8 (1991) .. -6.4 (1870) ... ... 11.6 (1991) .. -6.2 (1870)
24 Dec ... 10.7 (1843) .. -6.9 (1870) ... ... 11.3 (2023)*.. -6.7 (1830&1870)^

25 Dec ... 10.4 (1824&1983) .. -10.8 (1796) ...10.4 (1824)^..-10.8 (1796)

26 Dec ... 11.0 (2011) .. -5.4 (1798) ... ... 11.0 (2011) .. -5.4 (1786, 1798)
27 Dec ... 10.9 (2015) .. -8.4 (1798) ... ... 10.8 (2015) .. -8.4 (1798)
28 Dec ... 11.5 (1987) .. -8.2 (1798) ... ... 11.3 (1987) .. -8.2 (1798)
29 Dec ... 12.0 (1987) .. -4.9 (1874) ... ... 11.9 (1987) .. -5.3 (1908)^
30 Dec ... 11.4 (2021) .. -6.1 (1870) ... ... 11.3 (2021) .. -6.0 (1870)

31 Dec ... 12.9 (2021) .. -7.1 (1783) ... ... 12.9 (2021) .. -7.1 (1783)

____________________________________

^ Notes:

 1 Nov _ 1982 loses tie as 1894 incr 0.2 to 13.7, 1982 decr 13.5 to 13.2.

 1 Nov _ 1926 gains record with decr 1.6 to 1.1, 1934 remains 1.5, loses record.

 3 Nov _ 1980 gains record with decr 0.3 to 1.8, 1820 remains 1.9, loses record.

 5 Nov _ 1901 gains tie with decr 0.9 to 0.8, 1801 remains 0.8, tied.

10 Nov _ 2015 gains tie with decr 0.1 13.3 to 13.2, 1977 decr 0.2 13.4 to 13.2, tied.

11 Nov _ 2022 (14.2) in v2.0 replaced 2015 (13.8).

18 Nov _ 1887 loses record with incr -1.6 to -1.0, 1798 and 1871 (from -1.4) tied at -1.3 new record holders.

19 Nov _ 2003 gains tie with decr 12.6 to 12.5, 1994 decr 12.7 to 12.5 tied.

24 Nov _ 1904 loses record with incr of 1.1, -3.5 from -4.6, (1816 remains -3.6), also loses monthly minimum to 2010

27 Nov _ 1890 gains record with decr -2.5 to -2.7, 1915 loses record with incr -2.6 to -2.0

28 Nov _ 2010 gains monthly record, 23 Nov 1858 and 24 Nov 1904 both incr from lower values, 2010 remains -4.0

30 Nov _ 1796 gains tie (remains -1.6), 1973 incr -1.7 to -1.6, tied. 

 3 Dec _ 1985 revised in v2.0.1.0 to 12.1 from 12.0 in v2.0. 

10 Dec _ 1856 gains tie, decr 10.8 to 10.7, 1997 decr 10.9 to 10.7, tied.

14 Dec _ 2006 gains record, remains 11.5, 1912 decr 11.8 to 11.2. (1929 11.7 to 11.0)

24 Dec _ 2022 replaces 1843 (10.7) in v2.0 records. 1843 data not adjusted in v2.0. 

24 Dec _ 1830 gains tied share as 1870 up 0.2 -6.9 to -6.7, 1830 remains -6.7.

25 Dec _ 1983 loses tied share, decr 10.4 to 10.2, 1824 remains 10.4. 

29 Dec _ 1908 gains record, decr -4.8 to -5.3, 1874 loses record, incr -4.9 to -4.8.

 

_ - - - - - - - - _

other notables __ Warm _______________________ Cold

Date __ Year ___ CET 2.0 __ CET legacy ____ Date __ Year ___ CET 2.0 __ CET legacy 

2 Nov __ 1811 ___ 14.2 ____ same _______ 4 Nov __ 1901 ___ 1.5 _____ 1.0

_________________________________________ 6 Nov __ 1782 ___ 0.9 _____ same

 9 Nov _ 2020 ___ 12.1 ____ same ________ 7 Nov __ 1782 ___ 0.5 _____ same _ 1836 0.9 same

10 Nov _ 2020 ___ 12.3 ____ same ________8 Nov __ 1816 ___-0.8 _____ same _ 1837 -0.7 same

_________________________________________12 Nov __ 1828 ___-0.7 _____ same

_________________________________________13 Nov __ 1825 ___-0.8 _____ same _ 1925 -0.7 (was -0.9)

_________________________________________16 Nov __ 1780 ___-1.9 _____ same

_________________________________________ 17 Nov __ 1930 ___-1.4 _____-1.7 _ 1861 _ -1.3 (was -1.5)

22 Nov _ 1906 ___ 13.0 ____ 13.1 ________ 22 Nov __ 1880 ___-1.5 _____-1.3

23 Nov _ 1980 ___ 12.5 ____ 12.8 ________ 23 Nov __ 1993 ___-3.0 _____-2.9

_________________________________________ 27 Nov __ 1904 ___-2.4 _____-2.3

_________________________________________ 28 Nov __ 1890 ___-2.5 _____ -2.2 _ (1787, 1807 -2.2 same)

29 Nov _ 2000 ___ 11.9 ____ 12.1 ________ 29 Nov __ 2010 ___-2.5 _____ same

30 Nov _ 1939 ___ 12.0 ____ 11.9 _________ 

 1 Dec __ 1939 ___ 11.9 ____ 12.0 _________ 2 Dec ___ 1879 ___-4.2 _____ same

 3 Dec __ 1953 ___ 11.8 ____ same 

 5 Dec __ 1888 ___ 11.6 ____ 11.1 __________ 5 Dec ___ 1879 ___-3.6 _____ -3.2

____________________________________________6 Dec ___ 2010 ___-3.8 _____ same _ 1879 -3.7 (was -3.6)

____________________________________________7 Dec ___ 2010 ___-3.5 _____ same

 8 Dec __ 2015 ___ 11.3 _____ 11.4 __________8 Dec ___ 1812 ___-4.4 _____ same

 9 Dec __ 1856 ___ 11.5 _____ 11.7 __________9 Dec ___ 1812 ___-3.9 _____ same

___________________________________________10 Dec ___ 1981 ___-4.2 _____ -4.0

12 Dec __ 2000 ___ 11.8 ____ 12.1 _________11 Dec ___ 1819 ___-6.0 _____ same

___________________________________________13 Dec ___ 1878 ___-4.5 _____ -4.2 _ 1920 -4.4 (was -5.1)

14 Dec __ 1929 ___ 11.0 ____ 11.7 _________ 14 Dec ___ 1899 ___-5.2 _____ -4.8

18 Dec __ 2014 ___ 11.8 ____ same ________ 16 Dec ___ 1788 ___-5.7 _____ same

19 Dec __ 1993 ___ 11.4 ____ 11.6 _________ 19 Dec ___ 1859 ___-5.6 _____ -5.7

21 Dec __ 1828 ___ 11.2 ____ same ________

22 Dec __ 1828 ___ 11.2 ____ same ________ 22 Dec ___ 1870 ___-5.2 _____ -5.3 __ 1892 -4.8 (same)

23 Dec __ 1843 ___ 11.4 ____ same ________ 23 Dec ___ 1891 ___-5.7 _____ -4.4

___________________________________________ 25 Dec ___ 1830 ___-6.6 (same), 2010 -5.9 (same)

26 Dec __ 1988 ___ 10.7 ____ 10.9 _________ 25 Dec ___ 1878 ___-6.3 _____ -5.8

30 Dec __ 1834 ___ 11.0 ____ same ________ 30 Dec ___ 1788 ___-5.9 _____ same

31 Dec __ 1859 ___ 11.0 ____ 11.1 

(note the lowest value added to data base for Dec 1786 was -5.4 on 26th)

 

 

 

 

Edited January 24 by Roger J Smith

[Roger J Smith]

Summary of changes to the record high daily means

With the change to v2.0, we have 51 new or altered records (in terms of years) with the following breakdown:

18 cases where one year replaced another year

 2 cases where a year replaced two tied years

 1 case where two tied years replaced a different year

13 cases where a year shed a tied partner and now stands alone

15 cases where a year acquired a tied partner

 1 case where a year in a tie acquired a new tied partner _ 1

 1 case where an existing tie became a three-way tie with the two original tied values still involved. _ 1

 

(total 51)

Then of the 315 records that stand the same as before in terms of years, which includes 6 ties with years unchanged, the differential in temperature is as follows (number in brackets refers to tied years maintaining their tie): 

up by 0.3 or more _ 6

up by 0.2 _ 7

up by 0.1 _ 35

same as before _ 163 (5)

down by 0.1 _ 63 (1)

down by 0.2 _ 31

down by 0.3 or more _ 10

(noting that "same as before" would include any records set 1772 to 1852 as long as they survived changes in other data)

(there were cases of changes as large as +1.1 and -0.7)

__________________

Changes to yearly totals (counting ties as 0.5 or in two cases 0.33)

-- a change from sole record to tied is -0.5. -- a change from tied to no share is also -0.5.

-- all changes are shown with a total where more than one occurred.

YEAR _ Changes _____ Net change __ cumulative net change (at intervals)

1772 -0.5 ____________ -0.5

1773 -0.5 ____________ -0.5

1775 +0.5 ____________ +0.5

1780 -0.5 _____________ -0.5

1781 -0.5 +0.5 ________ 0.0

1796 +0.5 ____________ +0.5

1804 +0.5 -0.5 ________ 0.0

1818 +0.5 _____________+0.5

1821 +1.0 _____________+1.0

1822 +0.5 _____________ +0.5

1824 +0.5 _____________ +0.5

1826 +1.0 _____________ +1.0 _________________ +3.0 to 1826

1831 -0.5 ______________ -0.5

1846 -1.0 ______________ -1.0

1852 -0.5 ______________ -0.5

1854 -0.5 ______________ -0.5

1856 +0.5 _____________ +0.5

1858 -0.5 ______________ -0.5

1865 -0.5 -0.5 __________-1.0

1866 -1.0 ______________ -1.0

1870 +0.5 ______________ +0.5

1873 -0.5 _______________ -0.5

1874 -1.0 _______________ -1.0

1875 -1.0 _______________ -1.0

1878 -1.0 _______________ -1.0

1880 -1.0 _______________ -1.0 ___________________ -5.5 to 1880

1886 +1.0 +1.0 -1.0 _____ +1.0

1893 -1.0 _______________ -1.0

1894 +0.5 _______________ +0.5

1895 +1.0 _______________ +1.0

1898 -0.5 +1.0 -0.5 _______ 0.0

1903 +0.5, -1.0 __________ -0.5

1906 -1.0 +0.5 ___________ -0.5

1912 -1.0 ________________ -1.0

1916 -1.0 ________________ -1.0 ______________ -7.0 to 1916

1918 +1.0 _______________ +1.0

1921 +1.0 _______________ +1.0

1922 +0.5 _______________ +0.5

1923 -1.0, +0.5 __________ -0.5

1926 -0.5 ________________ -0.5

1927 -0.17, +1.0 _________+0.83

1928 -1.0 ________________ -1.0

1931 -0.17 _______________ -0.17

1944 -0.5 ________________ -0.5

1945 -0.5 ________________ -0.5

1946 +0.5 _______________ +0.5

1947 +0.5 +1.0 __________ +1.5

1948 -0.5 ________________ -0.5

1955 +0.5 _______________ +0.5

1959 +0.5 -1.0 ___________ -0.5 ________________ -5.33 to 1959

1966 +0.5 ________________ +0.5

1969 +1.0 ________________ +1.0

1976 -0.5, -0.5 ___________ -1.0

1977 -1.0 -0.5 ____________ -1.5

1978 -1.0 -0.5 ____________ -1.5

1982 -0.5 -0.5 ____________ -1.0

1983 +0.5 -0.5 ____________ 0.0

1984 -0.5 _________________ -0.5

1989 -0.5 _________________ -0.5

1990 -0.5 _________________ -0.5

1994 -0.5 _________________ -0.5

1997 +0.5 -0.5 ____________ 0.0

1998 -0.5 _________________ -0.5 ________________ -11.33 to 1998

2002 +0.5, +0.33 _________ +0.83

2003 +0.5 +0.5 ___________ +1.0

2004 +0.5 ________________ +0.5

2005 +1.0 +1.0 +1.0 +1.0 _ +4.0

2006 -1.0 +1.0 ________________ 0.0

2007 +0.5 ____________________ +0.5

2008 +0.5 ____________________ +0.5

 

2011 +1.0 +1.0 +0.5 -0.5 ______ +2.0

2013 +0.5 _____________________ +0.5

2014 +1.0 _____________________ +1.0

2015 +0.5 _____________________ +0.5

2021 +1.0 -1.0 _________________ 0.0

The periods seeing considerable change were around 1865 to 1916 with mostly losses, and since 2000 mostly gains. There was a smaller trend towards loss of high mean daily records in the 1970s and early 1980s. A somewhat different perspective shows that 11.33 records were taken out of the period 1772-2001 and placed in the most recent 21 years. 2005 and 2011 take a total of six of those. Will follow up with a similar census of changes to record low daily means.


 

[Roger J Smith]

Changes in coldest daily mean CET records

 

With the change to v2.0, we have 43 new or altered records (in terms of years) with the following breakdown:

16 cases where one year replaced another year

 0 cases where a year replaced two tied years

1 case where two tied years replaced a different year

12 cases where a year shed a tied partner and now stands alone

12 cases where a year acquired a tied partner

1 case where a year gained two tied partners

1 case where a tie was replaced by a different tie (no years survived)

 

(total 43)

Then of the 323 records that stand the same as before in terms of years, which includes 9 ties with years unchanged, the differential in temperature is as follows (number in brackets refers to tied years maintaining their tie and in one case three tied were all the same as before): 

up by 0.3 or more _ 17

up by 0.2 _ 12 (1)

up by 0.1 _ 41

same as before _ 216 (8)

down by 0.1 _ 17

down by 0.2 _ 11

down by 0.3 or more _ 9

(noting that "same as before" would include any records set 1772 to 1852 as long as they survived changes in other data)

(there were cases of changes as large as 1.2 degrees.)

__________________

Changes to yearly totals (counting ties as 0.5 or in two cases 0.33)

-- a change from sole record to tied is -0.5. -- a change from tied to no share is also -0.5.

-- all changes are shown with a total where more than one occurred.

YEAR _ Changes _____ Net change __ cumulative net change (at intervals)

 

1778 __ +0.5 _________ +0.5

1785 __ +0.5 -1.0 _____ -0.5

1786 __ +0.5 __________+0.5

1796 __ +0.5 __________ +0.5

1798 __ +0.5 __________ +0.5

1799 __ +0.5 __________ +0.5

1801 __ +1.0 -0.5 ______ +0.5

1807 __ -0.5 -0.5 _______ -1.0

1810 __ +1.0 ___________ +1.0

1816 __ +0.5 +0.5 +1.0 _ +2.0 _____________________ +3.5 to 1816

1817 __ -0.5 ____________ -0.5

1820 __ -1.0 ____________ -1.0

1822 __ -1.0 ____________ -1.0

1823 __ -0.5 ____________ -0.5

1824 __ -0.5 ____________ -0.5 ______________________ +1.0 to 1824

1830 __ +0.5 ___________ +0.5

1835 __ +0.33 __________ +0.33

1836 __ +0.5 ___________ +0.5

1837 __ +0.5 +0.5 -1.0 __ 0.0

1845 __ +1.0 +0.5 ______ +1.5

1855 __ +1.0 ____________+1.0 __________________ +4.83 to 1855

1860 __ +0.5 -0.5 ________ 0.0 

1862 __ -0.67 ___________ -0.67

1866 __ -1.0 ____________ -1.0

1867 __ -0.5 ____________ -0.5

1869 __ -0.5 ____________ -0.5

1870 __ -0.5 ____________ -0.5

1871 __ -0.5 +0.5 ________ 0.0

1872 __ -0.5 _____________-0.5

1874 __ -1.0 _____________-1.0 ________________ +0.17 to 1874

1879 ____________________+0.5

1880 __ +1.0 ____________+1.0

1881 __ +0.5 ____________+0.5

1885 __ -0.5 +0.5 ________ 0.0

1886 __ +0.5 ____________+0.5 _________________ +2.67 to 1886

1887 __ -1.0 ____________ -1.0

1888 __ -1.0 -0.5 +0.5 ___-1.0

1890 __ -0.5 +1.0 ________+0.5

1891 __ -0.5 _____________-0.5

1892 __ -0.5 _____________-0.5 __________________ +0.17 to 1892

1894 __ +1.0 ____________+1.0

1895 __ +0.5 +1.0 _______ +1.5

1896 __ +0.5 ____________ +0.5 _________________ +3.17 to 1896

1899 __ -0.5 _____________ -0.5

1901 __ -0.5 -1.0 +0.5 ___ -1.0

1903 __ +0.5 _____________+0.5

1904 __ -1.0 _____________ -1.0

1907 __ -1.0 +0.5 ________ -0.5

1908 __ -0.5 +1.0 ________ +0.5

1909 __ -1.0, -0.5 ________ -1.5 _____________ -0.33 to 1909

1910 __ +1.0 ____________ +1.0 

1912 __+1.0 +1.0 -1.0 +0.5_ +1.5

1914 __ -0.5 ______________ -0.5

1915 __ -1.0 -1.0 _________ -2.0

1917 __ -0.5, -0.5 _________ -1.0

1919 __ -1.0 _______________-1.0

1920 __ -0.5 _______________ -0.5 ______________ -2.83 to 1920

1926 __ +1.0 ______________ +1.0

1931 __ +0.5 ______________ +0.5

1934 __ -1.0 _______________ -1.0

1945 __ +1.0 ______________ +1.0

1973 __ -0.5 _______________ -0.5

1980 __ +1.0 ______________ +1.0

1981 __ +0.33 _____________ +0.33

1991 __ +0.5 ______________ +0.5 _______________ 0.0 to 1991

______________________________

The pattern with changes to years for cold records is somewhat more random, with intervals of gain followed by loss at irregular intervals, the first part of the period (1772 to 1816) picks up regularly, then a short period of losses to 1824 is followed by a second interval of regular gains to 1855. After that the changes from equilibrium are rather small, indicating that as the period of adjustment began, the net effects were fairly random, and it can be said that the interval of adjusted temperatures gave as much to the early unchanged era as vice versa. Within the interval of changed data, the flows seemed to be mostly away from the period 1896-1920 towards 1855-95. There are not that many cold records to shift around after 1920, and no changes occurred after 1991. 

The most significant change is no doubt the loss for 24 Nov 1904 of both a daily record and the monthly extreme. Another loss for 1888 in mid-August is noteworthy. A lot of the other changes will not make impact in the estimation of most weather enthusiasts, I would dare say. Both 1980 and 1981 managed to make their way further into the cold records, and in fact the most recent year to suffer a net loss in record holding is 1973 which lost a share of a newly created tie (30 Nov) and that is the only loss of record on the cold side since 1934 lost 1st Nov to 1926. 

 

 

Edited May 19, 2022 by Roger J Smith

[Earthshine]

Hi Roger, thanks a huge amount for this impressive analysis!

[Roger J Smith]

Thanks, moving on now to list the new daily extremes for high maximum and low minimum, compared to the "legacy" records. Will do this in two-month groups but without as much commentary, just the old and new numbers. The few changes that I found (other than ties that dropped a member) are highlighted in bold. 4 Jan 2010 got another record (with the tie with 1970 for 8 Jan) when 1893 rose to -6.7 out of record position. I also added a few "near miss" cold lows in smaller type size. 

Obviously there are likely some more extreme values among the years before 1878 just based on their mean temperatures (mainly among the record low minima). Would have to think 20 Jan 1838 was at least -15 C for its minimum. 

 

High Maximum 1878-2022 _ Legacy vs v2.0 ____ Low Minimum 1878-2022 _ Legacy vs v2.0

 

DATE ___ Legacy High max __ v2.0 High max _____[]__Legacy Low min __ v2.0 Low min, year

01 Jan __ 14.3 _ 2022 ______14.5 _ 2022 ______ ___ -8.6 _ 1962 _____ -8.6 _ 1962

02 Jan __ 12.9 _ 1910,76 __ 12.9 _ 1976 ______ ___ -8.7 _ 1962 _____ -8.7 _ 1962

03 Jan __ 12.7 _ 1932,48 __ 12.6 _ 1932,48 ___ ___ -7.8 _ 1962 _____ -7.8 _ 1962

04 Jan __ 13.2 _ 1916 _____ 13.1 _ 1957 ______ ___ -7.2 _ 1893 _____ -6.9 _ 2010

05 Jan __ 13.3 _ 1957,83 __ 13.4 _ 1983 ______ ___ -8.6 _ 1893 _____ -8.2 _ 1893

06 Jan __ 12.7 _ 1916,28 __ 12.7 _ 1916 ______ __ -10.7 _ 1894 ____ -10.9 _ 1894

07 Jan __ 12.9 _ 2005 _____ 13.0 _ 2005,2020__ __-9.7 _ 1894 _____-10.0 _ 1886 (9.1 _ 1894) (-8.4 _ 2010)

08 Jan __ 12.8 _ 2007 _____ 13.0 _ 2007 ______ ___ -7.7 _ 1970, 2010 _-8.7 _ 1886 (-7.7_1970,2010)

09 Jan __ 14.0 _ 2015 _____ 14.2 _ 2015 ______ ___ -6.5 _ 1918 _____ -6.5 _ 1892

10 Jan __ 12.7 _ 1971 _____ 12.7 _ 1971 ______ ___ -8.0 _ 1968, 82__ -8.0 _ 1968, 82

11 Jan __ 12.3 _ 2007 _____ 12.4 _ 2005, 2007 ___ -8.2 _ 1879 _____ -9.2 _ 1879

12 Jan __ 13.1 _ 2007 _____ 13.3 _ 2007 ______ __ -10.1 _ 1963 ____ -10.2 _ 1879 (-10.1 _ 1963 _ -9.8 _ 1987)

13 Jan __ 12.3 _ 2011 _____ 12.5 _ 2011 ______ ___ -9.6 _ 1987 _____ -9.7 _ 1987

14 Jan __ 12.7 _ 1968 _____ 12.7 _ 1968 ______ __ -12.9 _ 1982 ____ -12.8 _ 1982 

15 Jan __ 13.1 _ 1954 _____ 13.1 _ 1954 ______ __ -12.7 _ 1982 ____ -12.7 _ 1982

16 Jan __ 13.1 _ 1993 _____ 13.1 _ 1993 ______ __ -12.7 _ 1881 ____ -12.5 _ 1881

17 Jan __ 12.4 _ 1934 _____ 12.4 _ 1934 ______ __ -11.0 _ 1881 ____ -11.7 _ 1881

18 Jan __ 13.2 _ 2008 _____ 13.3 _ 2008 ______ __ -11.0 _ 1891 ____ -11.2 _ 1891

19 Jan __ 13.6 _ 1930 _____ 13.8 _ 1930 ______ __ -11.1 _ 1891 ____ -11.7 _ 1891

20 Jan __ 12.9 _ 2008 _____ 13.1 _ 2008 ______ __ -11.5 _ 1881 ____ -12.2 _ 1881

21 Jan __ 12.4 _ 1993 _____ 12.5 _ 2024^______ __ -13.4 _ 1940 ____ -13.3 _ 1940 (-12.9 _ 1881)

22 Jan __ 12.5 _ 1878 _____ 12.0 _ 1878 ______ __ -12.3 _ 1881 ____ -12.5 _ 1881

23 Jan __ 13.0 _ 1884 _____ 13.0 _ 2024^______ __-13.2 _ 1963 _____ -13.2 _ 1963

24 Jan __ 13.7 _ 2016 _____ 13.9 _ 2016 ______ __ -12.7 _ 1963 _____ -12.8 _ 1963

25 Jan __ 13.5 _ 2016 _____ 13.7 _ 2016 ______ __ -10.7 _ 1963 _____ -10.6 _ 1963 (-10.2_1881)

26 Jan __ 13.2 _ 2003 _____ 13.2 _ 2003 ______ __ -10.6 _ 1945 ____ -10.6 _ 1945

27 Jan __ 13.4 _ 2002 _____ 13.4 _ 2002 ______ __ -10.3 _ 1945 ____ -10.3 _ 1945

28 Jan __ 12.6 _ 2018 _____ 12.7 _ 2018 ______ __-11.1 _ 1979 ____  -11.2 _ 1979

29 Jan __ 13.0 _ 2002 _____ 13.0 _ 2002, 2013 __ -8.9 _ 1947 _____ -9.0 _ 1947

30 Jan __ 12.7 _ 1975 _____ 12.9 _ 1898 _____ ___ -8.7 _ 1947 _____ -8.7 _ 1947

31 Jan __ 12.6 _ 2016 _____ 12.8 _ 2016 _____ ___ -9.2 _ 1972 _____ -9.2 _ 1972

^ 21 Jan 2024 new record, 1993 stayed at 12.4 C in v2.0.

^ 23 Jan 2024 new record, 2018 (12.7) replaced 1884 (12.3) in v2.0.

==============================

High Maximum 1878-2022 _ Legacy vs v2.0 ____ Low Minimum 1878-2022 _ Legacy vs v2.0

DATE ___ Legacy High max __ v2.0 High max _____[]__Legacy Low min __ v2.0 Low min, year

01 Feb __ 13.3 _ 2016 _____ 13.5 _ 2016 _____ ___ -9.7 _ 1956 _____ -9.8 _ 1956

02 Feb __ 13.5 _ 2004 _____ 13.8 _ 2004 _____ __ -10.0 _ 1956 ____ -10.0 _ 1956

03 Feb __ 14.2 _ 2004 _____ 14.5 _ 2004 _____ __ -10.4 _ 1956 ____ -10.5 _ 1956

04 Feb __ 14.5 _ 2004 _____ 14.8 _ 2004 ______ ___-9.7 _ 1956 _____ -9.8 _ 1956

05 Feb __ 13.1 _ 1990 _____ 13.2 _ 1990, 2004___-9.2 _ 1917 _____ -9.6 _ 1917

06 Feb __ 13.4 _ 1989 _____ 13.6 _ 1989 ______ __ -11.0 1917  ____ -10.9 _ 1917

07 Feb __ 12.9 _ 1990 _____ 13.0 _ 1990 ______ __ -11.7 1917 _____ -12.3 _ 1895 (-10.7_1917)

08 Feb __ 12.6 _1903, 2000__12.6_ 1933, 2000__ -13.5 _ 1895 ____ -13.7 _ 1895

09 Feb __ 14.1 _ 2008 _____ 14.4 _ 2008 ______ __ -12.9 _ 1895 ____ -12.5 _ 1895

10 Feb __ 14.6 _ 1899 _____ 14.7 _ 1899 ______ __ -11.3 _ 1895 ____ -11.7 _ 1895

11 Feb __ 13.7 _ 1939 _____ 13.7 _ 1939 ______ ___ -8.6 _ 1986 _____ -8.5 _ 1986

12 Feb __ 14.3 _ 1998 _____ 14.3 _ 1998 ______ __ -10.1 _ 1895 _____ -9.9 _ 1895

13 Feb __ 16.4 _ 1998 _____ 16.4 _ 1998 ______ __ -11.1 _ 1895 ____ -11.2 _ 1895

14 Feb __ 15.8 _ 1998 _____ 15.9 _ 1998 ______ __ -12.5 _ 1929 ____ -12.6 _ 1929

15 Feb __ 14.2 _1998,2019__16.3 _ 2024^______ __ -12.1 _ 1929 ____ -11.5 _ 1929

16 Feb __ 14.8 _ 2022 _____ 15.0 _ 2022 ______ ___ -7.2 _ 1969, 1985 _ -7.3 _ 1969 (-7.2 1985)

17 Feb __ 14.2 _1878,1920__14.9 _ 1878^_____ ___ -9.2 _ 1929 _____ -8.6 _ 1929

18 Feb __ 15.0 _ 1945 _____ 15.2 _ 1945 ______ ___ -9.8 _ 1929 _____ -9.8 _ 1929

19 Feb __ 13.5 _ 1961 _____ 13.5 _ 1961 ______ ___ -8.7 _ 1892 _____ -9.0 _ 1892

20 Feb __ 14.1 _ 2017 _____ 14.3 _ 2017 ______ ___ -7.5 _ 1955 _____ -7.5 _ 1955

21 Feb __ 15.0 _ 2019 _____ 15.2 _ 2019 ______ ___ -8.2 _ 1986 _____ -8.2 _ 1986

22 Feb __ 15.0 _ 2019 _____ 15.2 _ 2019 ______ ___ -6.3 _ 1986 _____ -6.5 _ 1942

23 Feb __ 16.2 _ 2019 _____ 16.4 _ 2019 ______ ___ -7.0 _ 1947 _____ -7.0 _ 1947

24 Feb __ 15.9 _ 2019 _____ 16.1 _ 2019 ______ __ -13.6 _ 1947 ____ -13.6 _ 1947

25 Feb __ 17.7 _ 2019 _____ 17.9 _ 2019 ______ __ -12.1 _ 1947 ____ -12.1 _ 1947

26 Feb __ 18.4 _ 2019 _____ 18.6 _ 2019 ______ ___ -8.0 _ 1947 _____ -8.1 _ 1947

27 Feb __ 16.3 _ 2019 _____ 16.5 _ 2019 ______ ___ -6.0 _ 1955 _____ -6.0 _ 1955

28 Feb __ 16.0 _ 1959 _____ 16.0 _ 1959 ______ ___ -7.8 _ 1955 _____ -7.9 _ 1955

29 Feb __ 15.5 _ 1960 _____ 15.5 _ 1960 ______ ___ -4.9 _ 1904 _____ -4.6 _ 1904

_________________

^ 15 Feb 2024 16.4C broke 14.4 C in v2.0. 

^ 17 Feb 2023 14.2 C tied the legacy values but fell short of the boosted 1878 v2.0 value.

Edited February 19 by Roger J Smith

[Roger J Smith]

Second instalment of the updated extremes (high max, low min) in CET v2.0. Very few changes found, Apr 2021 lost one of its records to 1911, and 2013 lost a share of 31 March with 1955, both due to slight upward adjustments. 

 

 

High Maximum 1878-2022 _ Legacy vs v2.0 ___ Low Minimum 1878-2022 _ Legacy vs v2.0

DATE ___ Legacy High max __ v2.0 High max ____[]__Legacy Low min __ v2.0 Low min, year

 

01 Mar __ 14.9 _ 1959 ______ 14.9 _ 1959 _______ ___ -7.1 _ 1929 ______ -7.0 _ 1929*

02 Mar __ 16.5 _ 1977 ______ 16.5 _ 1977 _______ ___ -6.7 _ 1965 ______ -6.6 _ 1965

03 Mar __ 14.3 _ 1957 ______ 14.3 _ 1957 _______ ___ -9.3 _ 1965 ______ -9.3 _ 1965

04 Mar __ 16.0 _ 1928 ______ 16.3 _ 1928 _______ ___ -7.2 _ 1890, 1909__-7.8 _ 1890

05 Mar __ 16.0 _ 1961 ______ 16.0 _ 1961 _______ ___ -9.4 _ 1909 ______ -9.0 _ 1909

06 Mar __ 15.3 _ 1961 ______ 15.2 _ 1961 _______ ___ -6.2 _ 1962 ______ -6.2 _ 1962

07 Mar __ 14.9 _ 1906 ______ 14.8 _ 2015 _______ ___ -9.3 _ 1947 ______ -9.4 _ 1947

08 Mar __ 15.1 _ 1961 ______ 15.1 _ 1961 _______ ___ -6.6 _ 1947 ______ -6.6 _ 1947

09 Mar __ 19.9 _ 1948 ______ 19.9 _ 1948 _______ ___ -7.5 _ 1917 ______ -7.1 _ 1917

10 Mar __ 17.4 _ 1929 ______ 17.5 _ 1929 _______ ___ -6.3 _ 1883 ______ -6.1 _ 1883

11 Mar __ 18.4 _ 1957 ______ 18.4 _ 1957 _______ ___ -5.0 _ 1958 ______ -5.0 _ 1958

12 Mar __ 18.4 _ 1957 ______ 18.5 _ 1957 _______ ___ -6.4 _ 1891 ______ -7.5 _ 1891

13 Mar __ 17.2 _ 1991 ______ 17.3 _ 1991 _______ ___ -6.3 _ 1887 ______ -6.4 _ 1887

14 Mar __ 17.9 _ 1948 ______ 17.9 _ 1948 _______ ___ -6.7 _ 1887 ______ -6.6 _ 1887 

15 Mar __ 17.9 _ 1961 ______ 18.0 _ 1961 _______ ___ -5.4 _ 1962 ______ -5.4 _ 1962

16 Mar __ 20.0 _ 1961 ______ 20.0 _ 1961 _______ ___ -4.6 _ 1909 ______ -4.8 _ 1909

17 Mar __ 19.3 _ 1990 ______ 19.4 _ 1990 _______ ___-5.1 _ 1887 ______ -5.2 1887, 1909

18 Mar __ 19.6 _ 1990 ______ 19.7 _ 1990 _______ ___-4.6 _ 1900 ______ -5.0 _ 1900

19 Mar __ 17.6 _ 1972 ______ 17.5 _ 1972 _______ ___ -4.5 _ 1887 ______ -4.6 _ 1887

20 Mar __ 17.5 _ 1929 ______ 17.2 _ 1929 _______ ___ -7.7 _ 1930 ______ -7.3 _ 1930

21 Mar __ 17.8 _ 1927 ______ 17.8 _ 1927 _______ ___ -6.0 _ 1899 ______ -6.0 _ 1899

22 Mar __ 18.0 _ 2022 ______ 18.1 _ 2022 _______ ___ -5.3 _ 1899 ______ -4.7 _ 1899

23 Mar __ 19.4 _ 1945 ______ 19.4 _ 1945 _______ ___ -4.8 _ 1899 ______ -4.7 _ 1899

24 Mar __ 18.9 _ 2012 ______ 19.1 _ 2012 _______ ___ -6.3 _ 1883 ______ -6.7 _ 1883

25 Mar __ 19.1 _ 1953 ______ 19.1 _ 1953^______ ___ -4.4 _ 1883 ______ -4.4 _ 1883

26 Mar __ 18.8 _ 2012 ______ 18.9 _ 2012^______ ___ -4.2 _ 1901 ______ -4.2 _ 1901

27 Mar __ 19.5 _ 2012 ______ 19.6 _ 2012^______ ___ -4.4 _ 1881 ______ -4.6 _ 1881

28 Mar __ 20.3 _ 1929 ______ 20.5 _ 1929 _______ ___ -3.9 _ 1901 ______ -3.8 _ 1901

29 Mar __ 22.1 _ 1965 ______ 22.2 _ 1965 _______ ___ -4.9 _ 1901 ______ -5.1 _ 1901

30 Mar __ 21.2 _ 2021______ 21.3 _ 2021*_______ ___ -3.7 _ 1915 ______ -3.9 _ 1915

31 Mar __ 20.2 _ 2021 ______ 20.4 _ 2021 _______ ___ -3.8 _ 1955, 2013__-3.8 _ 1955 (-3.7 2013)

------------------------------

^ note: 25th to 27th had high daily means (>14 C) in 1777 and may have had warmer days than these record values. 

* (30th 2017 was 19.3) * (min 1st 2018 was -6.3)

======================================================

 

High Maximum 1878-2022 _ Legacy vs v2.0 ____ Low Minimum 1878-2022 _ Legacy vs v2.0

DATE ___ Legacy High max __ v2.0 High max ____[]__Legacy Low min __ v2.0 Low min, year

01 Apr __ 19.1 _ 1999 ______ 19.1 _ 1999 _______ ___ -4.0 _ 1967 ______ -4.1 _ 1967

02 Apr __ 20.8 _ 1946 ______ 20.8 _ 1946 _______ ___ -4.9 _ 1917 ______ -4.9 _ 1917

03 Apr __ 23.5 _ 1946 ______ 23.4 _ 1946 _______ ___ -3.9 _ 1917 ______ -4.0 _ 1917

04 Apr __ 22.0 _ 1946 ______ 22.0 _ 1946 _______ ___ -2.8 _ 1990 ______ -3.0 _ 1990

05 Apr __ 19.9 _ 2020 ______ 20.0 _ 2020 _______ ___ -3.1 _ 1990 ______ -3.3 _ 1990 

06 Apr __ 20.3 _ 2011 ______ 20.3 _ 2011 _______ ___ -2.4 _ 1911,1990 __ -2.6 1990 (-2.5 1911)

07 Apr __ 18.6 _ 1933 ______ 18.5 _ 1933 _______ ___ -3.3 _ 2021 ______ -3.1 _ 2021

08 Apr __ 20.3 _ 1969 ______ 20.5 _ 1969 _______ ___ -3.6 _ 1968 ______ -3.6 _ 1968

09 Apr __ 21.4 _ 2017 ______ 21.5 _ 2017 _______ ___ -3.2 _ 1973 ______ -3.2 _ 1973

10 Apr __ 22.0 _ 2020 ______ 22.1 _ 2020 _______ ___ -1.9 _ 1924 ______ -2.4 _ 1924

11 Apr __ 21.7 _ 2020 ______ 21.8 _ 2020 _______ ___ -3.4 _ 1978 ______ -3.4 _ 1978

12 Apr __ 20.8 _ 2020 ______ 20.9 _ 2020 _______ ___ -2.0 _ 2021 ____ -2.0 _1911,1912 (-1.8 2021)

13 Apr __ 19.3 _ 1945 ______ 19.3 _ 1945 _______ ___ -2.3 _ 2021 ______ -2.1 _ 2021

14 Apr __ 21.5 _ 2007 ______ 21.5 _ 2007 _______ ___ -3.3 _ 1892 ______ -3.1 _ 1892

15 Apr __ 23.3 _ 1949 ______ 23.3 _ 1949 _______ ___ -3.6 _ 1892 ______ -3.3 _ 1892

16 Apr __ 25.0 _ 2003 ______ 25.0 _ 2003 _______ ___ -2.3 _ 1892 ______ -2.2 _ 1892

17 Apr __ 22.4 _ 2003 ______ 22.4 _ 2003 _______ ___ -2.4 _ 1892 ______ -2.5 _ 1892

18 Apr __ 22.4 _ 2018 ______ 22.4 _ 2018 _______ ___ -2.8 _ 1892 ______ -2.9 _ 1892

19 Apr __ 24.3 _ 2018 ______ 24.3 _ 2018 _______ ___ -2.3 _ 1892 ______ -2.5 _ 1892

20 Apr __ 23.4 _ 1893 ______ 23.5 _ 1893 _______ ___ -1.7 _ 1969 ______ -1.7 _ 1969

21 Apr __ 23.7 _ 1893 ______ 23.4 _ 1893* ______ ___ -2.3 _ 1936 ______ -2.3 _ 1936, 1997

22 Apr __ 23.4 _ 2011 ______ 23.5 _ 2011 _______ ___ -1.0 _ 1879 ______ -1.1 _ 1879

23 Apr __ 22.4 _ 2011 ______ 22.5 _ 2011 _______ ___ -2.3 _ 1936 ______ -2.3 _ 1936

24 Apr __ 21.9 _ 1893 ______ 21.9 _ 1893 _______ ___ -3.0 _ 1908 ______ -3.0 _ 1908

25 Apr __ 22.9 _ 1893 ______ 23.1 _ 1893 _______ ___ -1.3 _ 1908 ______ -1.5 _ 1908

26 Apr __ 22.5 _ 1928 ______ 22.1 _ 1928 _______ ____-2.0 _ 1900 ______ -2.2 _ 1900 (-1.9 1985)

27 Apr __ 19.8 _ 1916,64 ___ 19.9 _ 1964 _______ ___ -0.7 _ 1906 ______ -1.2 _ 1906 

28 Apr __ 22.0 _ 1987 ______ 22.0 _ 1987^ ______ ___ -1.4 _ 2016 ______ -1.3 _ 2016

29 Apr __ 21.2 _ 1994 ______ 21.3 _ 1994^ ______ ___ -1.4 _ 1976 ______ -1.4 _ 1976

30 Apr __ 22.2 _ 1990 ______ 22.3 _ 1990^ ______ ___ -2.2 _ 1927 ______ -2.2 _ 1927*

------------------------

^ Maxima of 24-27 were likely in 1775 on these last three days of April. Minima around 10th-15th in 1837 very low, some could be records.

* 23.3 2011 not quite a record __ *-1.4 on 30th 1945. 

Edited May 28, 2022 by Roger J Smith

[Roger J Smith]

Moving along to the third segment of record high maxima and low minima, as updated by v2.0 changes ... 

 

High Maximum 1878-2022 _ Legacy vs v2.0 ____ Low Minimum 1878-2022 _ Legacy vs v2.0

DATE ___ Legacy High max __ v2.0 High max ____[]__Legacy Low min __ v2.0 Low min, year

 

01 May __ 23.7 _ 1966 ______ 23.7 _ 1966 _______ ___ -1.0 _ 1927 ______ -1.2 _ 1886 (-0.9_1927, -0.6 1945)

02 May __ 24.2 _ 1990 ______ 24.2 _ 1990 _______ ___ -0.4 _ 1979 ______ -0.6 _ 1979

03 May __ 25.5 _ 1990 ______ 25.5 _ 1990 _______ ___ -1.5 _ 1967 ______ -1.5 _ 1967

04 May __ 25.2 _ 1990,2006__ 25.3 _ 1990 _______ ___ -1.5 _ 1941 ______ -1.6 _ 1941

05 May __ 23.7 _ 1995 ______ 23.9 _ 1995 _______ ___ -0.5 _ 1982 ______ -0.5 _ 1979, 1982

06 May __ 23.9 _ 1995 ______ 24.0 _ 1995 _______ ___ +0.8 _ 1996 ______ +0.7 _ 1996

07 May __ 25.6 _ 2018 ______ 25.6 _ 2018 _______ ___ -0.5 _ 1892 ______ -0.6 _ 1892

08 May __ 25.0 _ 2016 ______ 25.0 _ 2016 _______ ___ -0.9 _ 1938 ______ -1.0 _ 1938

09 May __ 23.1 _ 2016 ______ 23.1 _ 2016 _______ _ +0.2 _1910, 1980, 1984 _ -0.5_1910

10 May __ 24.3 _ 1959 ______ 24.4 _ 1959 _______ ___ -1.3 _ 1879 ______ -1.3 _ 1879

11 May __ 25.2 _ 2008 ______ 25.2 _ 2008 _______ ___ -0.3 _ 1881 ______ -0.4 _ 1881

12 May __ 25.3 _ 1945 ______ 25.3 _ 1945________ ___ -0.9 _ 2020 ______ -0.8 _ 2020

13 May __ 24.4 _ 1965 ______ 24.5 _ 1965 _______ ___ -0.4 _ 2010 ______ -0.3 _ 2010

14 May __ 26.0 _ 1965 ______ 26.1 _ 1965 (25.9 _ 1992) _-0.6 _ 2020 ______ -0.4 _ 2020

15 May __ 23.7 _ 2000 ______ 23.7 _ 2000^______ ___ +0.2 _ 1915 ______ +0.2 _ 1915

16 May __ 24.5 _ 1952 ______ 24.5 _ 1952 _______ ___ -0.4 _ 1941 ______ -0.6 _ 1941

17 May __ 26.4 _ 1952 ______ 26.4 _ 1952 _______ ___ -1.3 _ 1935 ______ -1.3 _ 1935

18 May __ 26.2 _ 1952 ______ 26.2 _ 1952 _______ ___ -0.7 _ 1891 ______ -0.1 _ 1891

19 May __ 24.6 _ 1992 ______ 24.7 _ 1992 _______ ___ -0.4 _ 1891 ______ -0.2 _ 1891

20 May __ 25.5 _ 2020 ______ 25.5 _ 2020 _______ ___+1.9 _ 1956 ______ +1.9 _ 1894 (2.0 _ 1956)

21 May __ 26.2 _ 1918 ______ 26.4 _ 1918 _______ ___ +0.4 _ 1894 ______ +0.3 _ 1894

22 May __ 26.5 _ 1918 ______ 26.6 _ 1918 _______ ___ +0.4 _ 1894 ______+0.5 _ 1894

23 May __ 26.1 _ 1922 ______ 26.0 _ 1922 (25.8 _ 2010) _+2.0 _ 1905 ______ +1.8 _ 1905

24 May __ 25.3 _ 1992 ______ 25.4 _ 1992 _______ ___ +0.9 _ 1923 ______+1.4 _ 1923

25 May __ 27.7 _ 1953 ______ 27.6 _ 1953 _______ ___ +2.4 _ 1948 ______ +2.4 _ 1948

26 May __ 25.5 _ 2017 ______ 25.5 _ 2017 _______ ___ +1.7 _ 1914 ______ +1.6 _ 1914

27 May __ 25.6 _ 2005 ______ 25.5 _ 2005 _______ ___ +1.1 _ 1914 ______ +1.1 _ 1914

28 May __ 26.2 _ 1944 ______ 26.3 _ 1944 _______ ___ +1.3 _ 1899 ______ +1.2 _ 1899

29 May __ 29.0 _ 1944 ______ 28.9 _ 1944*______ ___ +2.8 _ 1927 ______ +2.8 _ 1927

30 May __ 27.4 _ 1944 ______ 27.4 _ 1944 _______ ___ +2.8 _ 1915,74 ___+2.7 _ 1880,1915,74

31 May __ 28.5 _ 1947 ______ 28.6 _ 1947 _______ ___ +0.8 _ 1975 ______ 0.8 _ 1975 (+1.2_1915)

_____________________________________

^ higher maxima may have occurred 15th May 1833. * 28.6 29th 1947

===========================================

High Maximum 1878-2022 _ Legacy vs v2.0 ____ Low Minimum 1878-2022 _ Legacy vs v2.0

DATE ___ Legacy High max __ v2.0 High max ____[]__Legacy Low min __ v2.0 Low min, year

 

01 Jun __ 26.8 _ 1922 ______ 27.0 _ 1922 _______ ___ 1.9 _ 1962 ______ 1.9 _ 1962

02 Jun __ 30.0 _ 1947 ______ 30.0 _ 1947 _______ ___ 2.6 _ 1991 ______ 2.4 _ 1991 (2.9 1989)

03 Jun __ 29.6 _ 1947 ______ 29.5 _ 1947 _______ ___ 3.9 _ 1975 ______ 3.8 _ 1975

04 Jun __ 27.5 _ 1933 ______ 27.5 _ 1933, 1980 ____1.8 _ 1991 ______ 1.6 _ 1991

05 Jun __ 28.4 _ 1942 ______ 28.4 _ 1942 _______ ___ 1.3 _ 1991 ______ 1.2 _ 1991 

06 Jun __ 29.9 _ 1950 ______ 29.9 _ 1950 _______ ___ 3.7 _ 1920 ______ 3.5 _ 1920

07 Jun __ 27.8 _ 1940 ______ 27.7 _ 1933, 1940 ____ 3.6 _ 2005 ______  3.7 _ 2005 

08 Jun __ 28.5 _ 1976 ______ 28.4 _ 1976 _______ ___ 3.1 _ 1985 ______ 2.9 _ 1985

09 Jun __ 28.3 _ 1940 ______ 28.2 _ 1940 _______ ___ 3.1 _ 1881 ______ 3.1 _ 1881

10 Jun __ 28.4 _ 1970^______ 28.6 _ 2023^_______ ___ 2.8 _ 1911 ______ 3.0 _ 1955

11 Jun __ 28.3 _ 1925 ______ 28.4 _ 1925 _______ ___ 4.7 _ 1942 ______ 4.7 _ 1942

12 Jun __ 25.8 _ 2006^_____ 28.4 _ 2023^_______ ___ 4.1 _ 1957 ______ 4.3 _ 1957, 2011

13 Jun __ 26.4 _ 1897^______27.5 _ 2023^ ______ ___ 3.5 _ 1892 ______ 3.6 _ 1892

14 Jun __ 25.1 _ 1887^______ 25.9 2023^ ______ ____ 3.7 _ 1973 ______ 3.6 _ 1973

15 Jun __ 26.9 _ 1896 ______ 27.1 _ 1896 _______ ___ 2.5 _ 1895 ______ 2.8 _ 1895 (3.0_1892)

16 Jun __ 27.5 _ 1957 ______ 27.5 _ 1957 _______ ___ 4.3 _ 1918 ______ 4.2 _ 1918

17 Jun __ 28.3 _ 1957 ______ 28.2 _ 1957, 2022*_ __ 2.9 _ 1916 ______ 3.2 _ 1916

18 Jun __ 29.4 _ 2000 ______ 29.2 _ 2000 _______ ___ 3.7 _ 1892 ______ 4.0 _ 1892

19 Jun __ 29.1 _ 2005,2017__ 30.1 _ 2005 (29.0 _ 2017) __ 3.6 _ 1915 ______ 3.8 _ 2004

20 Jun __ 27.5 _ 1989 ______ 27.5 _ 1989 _______ ___ 4.0 _ 1964 ______ 4.0 _ 1964

21 Jun __ 29.8 _ 2017 ______ 29.6 _ 1941, 2017 ___ ___ 4.0 _ 1903 ______ 3.5 _ 1903

22 Jun __ 28.1 _ 1935 ______ 28.1 _ 1935 _______ ___ 5.1 _ 1903 ______ 4.3 _ 1903

23 Jun __ 28.0 _ 1935 ______ 28.0 _ 1935 _______ ___ 4.1 _ 1957 ______ 4.0 _ 1957

24 Jun __ 29.2 _ 2020 ______ 29.0 _ 2020 _______ ___ 5.4 _ 1926 ______ 5.5 _ 1926, 1944

25 Jun __ 29.4 _ 2020 ______ 29.2 _ 2020 (29.0 _ 1976)_ 5.3 _ 1926,31 ___ 5.3 _ 1931 

26 Jun __ 30.0 _ 1878 ______ 29.4 _ 1878 (29.3 _ 1976) _ 5.1 _ 1918,29 ___ 5.1 _ 1918

27 Jun __ 29.9 _ 1976 ______ 29.9 _ 1976 ________ ___ 4.8 _ 1919 ______ 5.9 _ 1919, 1981

28 Jun __ 30.3 _ 1976 ______ 30.3 _ 1976 ________ ___ 5.2 _ 1921 ______ 5.4 _ 1904 (5.5_1921, 5.6_1981)

29 Jun __ 30.6 _ 2019 ______ 30.4 _ 2019 (30.0 _ 1976) _ 4.6 _ 1907 ______ 4.8 _ 1907

30 Jun __ 29.8 _ 1976 ______ 29.7 _ 1976 ________ ___ 5.3 _ 1972 ______ 5.3 _ 1972

___________

*2022 added to table after first appearance, tied the v2.0 value for 1957. 

the mean for the day (21.0) remained short of the 1917 mark. 

^ 10, 12, 13, 14 June new record high max in v2.0 as shown. 

(13 June 1897 was 26.1 in v2.0) (14 June 1896 25.2 in v2.0, 1887 was 25.0)

Edited June 15, 2023 by Roger J Smith

[SummerShower]

Does anyone know the rationale behind the database being changed?  And is this new version now 'the official' one, or merely just an alternative data set?

I guess the new data set doesn't adjust figures downwards for urban warming (hence many recent figures being corrected upwards) but I believe there is more to it.

Just interested to know really