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

[Midlands Ice Age]

3 hours ago, Greyhound81 said:

I am not an activist, I have never been to a protest in my life.  Anyone is entitled to thier views on AGW, but what is bullshit is the idea that the only reason the CET data has been changed is that it is part of a big conspiracy, which is what BFTP was suggesting.  It is an insult to the hard working people at the Met Office.

OK... fine .

Then why not state that in your reply.

So you discard BFTV's reason.   (basically that they have discarded the Redhill Aerodrome because of some underhand reason).

My reason for disagreeing with his point is that Redhill has not been a 'CET' station for many years.

The only real differences and unexplained changes are to the last 5 years. Why is that when we have seen many checks on the CET, each day, (even on here). Give us a reason that these have required an uplift? The last 2 years has seen changes of 25% of the warming of the last 40 years. It is not a small amount  in CET anomaly terms..

It will therefore attract the attention of many people.

If the recorded data is accurate (I believe it is) then there should bot be a need for any adjustments over the current monthly adjustment process. 

Is it that they have removed some UHI effect? If so, would it not be possible to tell people?

MIA

[Greyhound81]

2 hours ago, Midlands Ice Age said:

OK... fine .

Then why not state that in your reply.

So you discard BFTV's reason.   (basically that they have discarded the Redhill Aerodrome because of some underhand reason).

My reason for disagreeing with his point is that Redhill has not been a 'CET' station for many years.

The only real differences and unexplained changes are to the last 5 years. Why is that when we have seen many checks on the CET, each day, (even on here). Give us a reason that these have required an uplift? The last 2 years has seen changes of 25% of the warming of the last 40 years. It is not a small amount  in CET anomaly terms..

It will therefore attract the attention of many people.

If the recorded data is accurate (I believe it is) then there should bot be a need for any adjustments over the current monthly adjustment process. 

Is it that they have removed some UHI effect? If so, would it not be possible to tell people?

 

I would not know that unfortunatly, but I am sure there is a reasonable explanation.  If you really wanted to know, the best thing would be to email the Met Office?  

Also, I think I remember reading somewhere that in the earliest days of the CET, temperature readings were taken indoors because it was too cold to go outside.  If that is true (a very big if, I know), then that would be a much bigger problem than the changes over the last 5 years. 

[LetItSnow!]

12 hours ago, Midlands Ice Age said:

OK... fine .

Then why not state that in your reply.

So you discard BFTV's reason.   (basically that they have discarded the Redhill Aerodrome because of some underhand reason).

My reason for disagreeing with his point is that Redhill has not been a 'CET' station for many years.

The only real differences and unexplained changes are to the last 5 years. Why is that when we have seen many checks on the CET, each day, (even on here). Give us a reason that these have required an uplift? The last 2 years has seen changes of 25% of the warming of the last 40 years. It is not a small amount  in CET anomaly terms..

It will therefore attract the attention of many people.

If the recorded data is accurate (I believe it is) then there should bot be a need for any adjustments over the current monthly adjustment process. 

Is it that they have removed some UHI effect? If so, would it not be possible to tell people?

MIA

I think the best way and the only way you'd be able to accurately measure temperatures compared to old readings is if you're lucky enough to live in the countryside and own land and set up a station that's completely away from any building materials, and then compare the readings to official stations - that way you would be able to assess any real differences. Like on a hot day, if Heathrow was showing 36 but the rural station was showing 32, then it would be of interest. However if they were both showing 36 then you'd have your answer. I'm sure someone already has got a station like I described somewhere - and I don't mean  just someone's backgarden  I did that when I was a kid and wondered why I'd record 35-40C every summer. I'd love to start recording data again but living in an apartment complex...

Back to the topic though. I do think there is something to this UHI stuff but it requires far more proof that just guesswork. It's just a case of whether the warming that has occured already is being amplified and such. 

[BLAST FROM THE PAST]

On 05/06/2022 at 19:03, Greyhound81 said:

I am not an activist, I have never been to a protest in my life.  Anyone is entitled to thier views on AGW, but what is bullshit is the idea that the only reason the CET data has been changed is that it is part of a big conspiracy, which is what BFTP was suggesting.  It is an insult to the hard working people at the Met Office.

And you derived all that from my post…..with a beautiful ‘you denier’ response.  Go on, accuse me of also denying the holocaust too from my post. We move on
 

BFTP

[Roger J Smith]

If it hits 41.2 next weekend, you can always say "yes but it's only 41.0 legacy."

[Roger J Smith]

For the coming heat wave part two, in terms of the CET Tuesday the 19th is up against heavyweight daily records, mean 24.6 (24.5 legacy), max 33.0 (32.9 legacy) from 2006, while the 18th takes on a somewhat less formidable value from 1825 (mean daily 23.2 only in that case, they didn't start daily max or min until 1878 so the max records are from 2006, 30.9 both sets. At least 1825 will probably retain an earlier record mean set on 15th of 23.7. For Sunday 17th, a lower mean record of 22.3 (1834) is within reach perhaps too. That daily max record (as 1834 unavailable) was also 2006, 29.7 (legacy 29.6). 

I realize the core of the heat is expected to be a bit further east so maybe the 19th 2006 record will survive. We'll know soon enough.

[Roger J Smith]

We have looked over the primary daily records (high max, low min) so here are the rather few changes made to secondary records which are low max and high min ... will continue to edit in values, the first four months are available here ... should be finished with this table by some time late Tuesday I hope. 

CET low maximum records 1878-2022 ____ CET high minimum records 1878-2022

Date __ CET leg _ CET v2.0 ____________ CET leg _ CET v2.0 _______________

01 Jan _ -1.1 1962 _ -1.1 1962 _________10.9 2022 _10.9 2022

02 Jan _ -1.8 1893 _ -1.6 1893 _________ 8.9 1921 _ 8.7 1921

03 Jan _ -0.9 1941 _ -0.9 1941 _________10.5 1932 _10.4 1932

04 Jan _ -2.1 1894 _ -2.3 1894 _________ 9.7 1932 _ 9.7 1932

05 Jan _ -4.2 1894 _ -4.7 1894 _________ 9.5 1957 _ 9.5 1957

06 Jan _ -3.0 1894 _ -3.1 1894 _________ 9.2 1983 _ 9.2 1983

07 Jan _ -2.6 1894 _ -2.0 1894 _________ 8.8 1890 _ 8.8 1890

08 Jan _ -2.1 1982 _ -2.0 1982 _________ 8.2 1890 _ 7.9 1989

09 Jan _ -2.5 1982 _ -2.4 1982 _________ 8.2 1957,71 _8.3 1957

10 Jan _ -2.3 1982 _ -2.3 1879 _________10.4 1921 _10.5 1921

11 Jan _ -3.3 1987 _ -3.2 1987 _________ 8.8 1990 _ 8.8 1990

12 Jan _ -5.7 1987 _ -5.6 1987 _________ 8.4 1976 _ 8.4 1976

13 Jan _ -3.5 1987 _ -3.5 1987 _________ 8.8 2007 _ 8.8 2007

14 Jan _ -4.4 1881 _ -4.4 1881 _________ 9.5 2011 _ 9.5 2011

15 Jan _ -2.7 1881 _ -2.9 1881 _________ 8.3 1968 _ 8.4 1968

16 Jan _ -3.0 1985 _ -3.0 1985 _________ 9.8 1990 _ 9.7 1990

17 Jan _ -2.1 1940 _ -2.2 1940 _________ 9.3 1908 _ 9.3 1908

18 Jan _ -1.3 1881 _ -1.3 1891 _________ 8.0 1920 _ 8.0 1921

19 Jan _ -2.9 1881 _ -2.9 1881 _________ 9.9 1932 _ 9.9 1932

20 Jan _ -3.8 1940 _ -3.9 1940 _________ 9.9 1898 _ 9.7 1898

21 Jan _ -3.2 1881 _ -3.2 1881 _________ 9.6 1898 _ 9.5 1898

22 Jan _ -1.8 1963 _ 1.9 1963 _________ 8.7 1969 _ 8.7 1969

23 Jan _ -3.6 1963 _ -3.6 1963 _________ 9.2 1960 _ 9.2 1960

24 Jan _ -3.6 1963 _ -3.6 1963 _________ 8.2 2018 _ 8.1 2018

25 Jan _ -4.0 1881 _ -4.1 1881 _________ 9.7 2016 _ 9.6 2016

26 Jan _ -4.5 1945 _ -4.5 1945 _________ 8.4 1903 _ 8.1 1903

27 Jan _ -0.8 1945,54 _-1.2 1954 ________ 8.4 2016 _ 8.4 1903,2016

28 Jan _ -1.1 1895,1954 _-1.1 1954 _______ 8.8 1958 _ 8.8 1958

29 Jan _ -3.8 1947 _ -3.8 1947 _________ 9.0 1921 _ 8.9 1921

30 Jan _ -1.4 1947 _ -1.4 1947 _________ 8.5 1923 _ 8.4 2000

31 Jan _ -1.9 1954 _ -1.9 1954 _________ 8.9 2000 _ 8.9 2000

 

01 Feb _ -3.8 1956 _ -3.9 1956 _________ 9.8 1923 _ 9.4 1923

02 Feb _ -2.9 1956 _ -2.9 1956 _________10.3 1923 _10.0 1923

03 Feb _ -0.3 1956 _ -0.3 1956 _________ 9.7 2004 _ 10.0 2004

04 Feb _ -3.0 1912 _ -2.9 1912 _________10.8 2004 _10.8 2004

05 Feb _ -0.6 1912 _-0.3 1895,1912 _____ 10.5 2004 _10.5 2004

06 Feb _ -4.5 1895 _ -4.5 1895 _________ 8.8 2011 _ 8.9 2011

07 Feb _ -2.7 1895 _ -3.3 1895 _________ 8.7 1989 _ 8.7 1989

08 Feb _ -3.0 1895 _ -3.2 1895 _________10.1 1903 _ 9.4 1903

09 Feb _ -1.8 1895 _ -1.4 1895 _________ 9.4 1903 _ 9.6 1903

10 Feb _ -2.7 1985 _ -2.5 1985 _________ 9.4 1899 _ 9.5 1899

11 Feb _ -1.8 1947,85 _ -1.9 1929 _______ 9.1 1939 _ 9.1 1939

12 Feb _ -2.9 1929 _ -2.9 1929 _________ 8.8 2002 _ 8.7 1943

13 Feb _ -3.4 1929 _ -3.4 1929 _________ 7.6 1998 _ 7.4 1998

14 Feb _ -1.6 1929 _ -1.7 1895,1929 _____ 7.7 1882 _ 8.1 1882

15 Feb _ -3.9 1929 _ -3.3 1895 _________10.0 1958 _11.1 2024^

16 Feb _ -1.2 1947 _ -1.3 1947 _________ 9.4 1928 _ 9.7 1928

17 Feb _ -2.3 1947 _ -2.3 1947 _________ 8.1 1911 _ 8.4 2023*

18 Feb _ -0.8 1947 _ -0.8 1947 _________ 9.0 1911 _ 8.8 2023*

19 Feb _ -0.6 1892 _ -0.9 1892 _________ 8.4 1945,89 _8.4 1945

20 Feb _ -0.7 1947 _ -0.7 1947 _________ 9.7 1990 _ 9.7 1990

21 Feb _ -2.1 1947 _ -2.2 1947 _________ 8.5 2021 _ 8.8 1903

22 Feb _ -0.8 1947 _ -0.7 1947 _________ 8.6 1953 _ 8.5 1953

23 Feb __ 0.0 1947 __ 0.0 1947 _________ 8.8 1918 _ 8.6 1918

24 Feb _ -0.6 1956 _ -0.5 1956 _________ 9.5 1922 _ 9.4 1990

25 Feb __ 0.0 1986 __0.3 1929,86 ______ 8.0 1900 _ 8.0 1900

26 Feb _ -1.3 1929 _ -1.3 1929 _________ 9.9 1882 _ 9.6 1882

27 Feb _ -1.5 1929 _ -1.5 1929 _________ 9.0 1945 _ 9.0 1945

28 Feb _ -1.3 2018 _ -1.1 2018 _________ 8.6 1912 _ 8.5 1912

29 Feb __ 0.1 1904 __ 0.5 1904 _________ 8.5 1960 _ 8.8 1912

01 Mar _ -1.2 2018 _ -1.1 2018 _________ 8.9 1878 _ 9.1 1878

02 Mar __ 0.0 1892 _ -0.3 1892 _________ 8.9 1999 _ 8.8 1999

03 Mar _ -0.1 1892 _ -0.5 1892 _________ 8.4 1979 _ 8.4 1979

04 Mar __ 0.5 1965 __ 0.6 1965 _________ 8.1 1977 _ 8.2 1922

05 Mar __ 0.3 1947 __ 0.3 1947 _________ 7.8 1880 _ 7.8 1880

06 Mar _ -0.7 1942 _ -0.8 1942 _________ 9.4 1989 _ 9.4 1989

07 Mar __ 0.9 1931 __ 0.8 1931 _________ 8.6 1926,2002 _8.8 1926^

08 Mar __ 0.6 1917 __ 0.6 1917 _________10.0 2000 _ 9.8 1981,2000

09 Mar __ 0.7 1931 __ 0.7 1931 _________10.3 2000 _10.1 2000

10 Mar __ 0.9 1891 __ 0.7 1891 _________ 9.9 1957 _ 9.8 1957

11 Mar __ 0.5 1928 __ 0.6 1928 _________10.1 1981 _10.1 1981

12 Mar __ 1.0 1928 __ 1.0 1928 _________ 8.5 2017 _ 8.6 2017

13 Mar __ 2.4 1888 __ 2.1 1888 _________ 9.0 1961 _ 9.0 1961

14 Mar __ 1.9 1947 __ 1.8 1947 _________ 8.3 1912 _ 9.4 2024 (repl 8.3 1884)

15 Mar __ 1.4 1887 __ 1.3 1887 _________ 8.8 1957 _ 9.7 2024 (repl 8.9 1957)

16 Mar __ 0.9 1979 __ 0.9 1979 _________ 9.6 2004 _ 9.6 2004

17 Mar __ 1.5 1888,2018 _1.6 1888 ________10.4 2005 _10.2 2005

18 Mar __ 0.7 2018 __ 0.8 2018 _________ 9.4 1898 _ 9.1 1898,1993

19 Mar __ 1.6 1888 __ 1.5 1888 _________ 9.5 2017 _ 9.6 2017

20 Mar __ 2.8 1888 __ 2.9 1888 _________ 9.3 2017 _ 9.4 2017

21 Mar __ 2.4 1883 __ 2.3 1883 _________ 9.5 1931 _ 9.4 1931

22 Mar __ 1.9 1883 __ 1.8 1879 _________10.4 1927 _10.2 1927

23 Mar __ 0.8 2013 __ 0.9 2013 _________ 9.2 1936 _ 9.5 1886

24 Mar __ 0.4 1879 __ 0.4 1879 _________ 9.0 2005 _ 9.1 2005

25 Mar __ 0.1 1879 __ 0.2 1879 _________ 9.9 1981 _ 9.8 1981

26 Mar __ 1.1 1879 __ 1.1 1879 _________ 9.7 2006 _ 9.8 2006

27 Mar __ 3.0 2013 __ 3.0 1901 _________10.9 2006 _11.0 2006

28 Mar __ 2.8 1952 __ 2.9 1952 _________ 9.1 1981 _ 9.5 1890

29 Mar __ 2.1 1952 __ 2.2 1952 _________ 9.8 1945 _ 9.8 1945

30 Mar __ 3.4 1952 __ 3.5 1952 _________11.2 1998 _11.1 1998,2017

31 Mar __ 3.3 1922 __ 3.5 1922 _________10.7 2017 _10.8 2017

^ 7 Mar 1926 was 8.9 in v2.0, reduced to 8.8 in v2.0.1.0.  

01 Apr __ 3.1 1917 __ 3.3 1917 __________10.2 2011 _10.3 2011

02 Apr __ 3.3 1968 __ 3.2 1968 __________11.3 2011 _11.4 2011

03 Apr __ 3.1 1922 __ 2.8 1922 __________ 9.9 1985 _ 9.9 1985

04 Apr __ 5.0 1911 __ 5.2 1911 __________11.9 1926 _12.1 1926

05 Apr __ 2.3 1911 __ 2.4 1911 __________10.4 1999 _10.5 1999

06 Apr __ 4.1 1911 __ 4.1 1911 __________10.5 2014 _10.6 2014

07 Apr __ 4.1 1986 __ 4.2 1986 __________ 9.4 2014 _ 9.5 2014

08 Apr __ 4.9 1986 __ 4.9 1986 __________ 9.7 1937 _ 9.6 1937

09 Apr __ 6.0 1891,1917 _5.9 1917__________ 9.4 1999 _ 9.3 1999

10 Apr __ 4.1 1978 __ 3.9 1917 __________10.9 1928,37 _10.9 1937

11 Apr __ 5.4 1879 __ 5.2 1879 __________11.6 1981 _11.5 1981

12 Apr __ 3.7 1879 __ 3.8 1879 __________10.1 1949 _10.0 1943,49

13 Apr __ 3.7 1892 __ 3.5 1892 __________10.2 1939 _10.3 1939

14 Apr __ 2.3 1966 __ 2.3 1966 __________10.5 1905 _10.2 1905

15 Apr __ 3.3 1966 __ 3.4 1966 __________11.9 1945 _11.9 1945

16 Apr __ 4.6 1966 __ 4.6 1966 __________11.8 1945 _11.9 1945

17 Apr __ 5.3 1966 __ 5.3 1966 __________ 9.7 2018 _ 9.9 2018

18 Apr __ 6.0 1918 __ 6.3 1918,83 ________11.6 2018 _11.7 2018

19 Apr __ 5.1 1881 __ 4.9 1881 __________11.0 2018 _11.1 2018

20 Apr __ 5.9 1881 __ 5.9 1881 __________ 9.8 1893 _ 9.8 1893

21 Apr __ 6.4 1918 __ 5.4 1918 __________ 9.9 1895,1963 _9.9 1910

22 Apr __ 7.6 1936 __ 7.5 1888,1936 _____11.1 2018 _11.3 2018

23 Apr __ 4.3 1908 __ 4.3 1908 __________ 9.9 1993 _ 9.8 1993

24 Apr __ 4.0 1908 __ 4.2 1908 __________12.3 2007 _12.4 2007

25 Apr __ 5.0 1908 __ 5.0 1908 __________12.2 2007 _12.3 2007

26 Apr __ 6.1 1981 __ 6.2 1981 __________10.3 1930 _10.2 1896

27 Apr __ 5.7 1919 __ 5.9 1919 __________11.1 1928 _10.8 1928

28 Apr __ 7.7 1892,1919 _ 7.4 1919 ________12.1 1994 _11.9 1994

29 Apr __ 7.6 1945 __ 7.6 1945 __________10.1 1963 _10.1 1963 (possibly 13-14 in 1775)

30 Apr __ 6.7 1945 __ 6.7 1945 __________10.4 1987 _10.5 1987

(table continues ... next two posts)

NOTE:

 

^ 11.1 on 15 Feb 2024 replaced 11.0 in v2.0 (1958)

* 8.4 17 Feb 2023 replaced 8.1 in v2.0 1911. 

* 8.8 18 Feb 2023 replaced 8.5 in v2.0 1945. (CET legacy was 9.0 in 1911).

 

Edited March 16 by Roger J Smith

[Roger J Smith]

 

CET low maximum records 1878-2022 ____ CET high minimum records 1878-2022

Date __ CET leg _ CET v2.0 ____________ CET leg _ CET v2.0 _______________

 

01 May __ 6.7 1979 _ 6.6 1979 _________12.1 2005 _11.8 2005

02 May __ 8.1 1979 _ 8.0 1979 _________10.3 2005 _10.5 2005

03 May __ 6.0 1892 _ 6.0 1892 _________10.5 2005 _10.8 2005

04 May __ 8.4 1979 _ 8.5 1979 _________12.5 2008 _12.6 2008

05 May __ 8.5 1979 _ 8.4 1979 _________11.0 2008 _11.2 2008

06 May __ 8.6 1932 _ 8.6 1932 _________11.1 1962 _11.1 1958,62

07 May __ 6.7 1879 _ 6.4 1879 _________12.3 2011 _12.4 2011

08 May __ 8.1 1904 _ 7.8 1904 _________13.5 2011 _13.7 2011

09 May __ 8.3 1883 _ 8.2 1883 _________14.2 1945 _14.2 1945

10 May __ 8.6 1883 _ 8.6 1883 _________13.1 2016 _13.3 2016

11 May __ 9.0 1886 _ 9.4 1995 _________12.5 2016 _12.7 2016

12 May __ 8.7 1897 _ 9.5 1886,1897 _____13.0 1959 _13.0 1959

13 May __ 6.7 1915 _ 7.1 1915 _________14.1 1945 _14.1 1945

14 May __ 9.1 1935 _ 9.2 1935 _________11.8 1969,92 _11.6 1943,47,92,98

15 May __ 9.3 1879 _ 9.6 1879,1941 _____13.2 2000 _13.2 2000

16 May __ 7.9 1935 _ 7.9 1935 _________12.2 2017 _12.3 2017 (possibly 14-15 in 1833)

17 May __ 8.5 1995 _ 8.6 1935 _________12.7 2002 _12.6 2002

18 May __ 9.4 1996 _ 9.6 1996 _________13.1 1997 _13.1 1896

19 May __ 9.7 1894 _ 9.8 1894 _________13.1 1888 _12.7 1888

20 May __ 8.8 1907 _ 9.3 1906 _________12.1 2014 _12.3 2014

21 May __ 9.5 1891 _ 9.4 1891 _________12.1 1916 _11.9 1922

22 May __ 9.9 1954 _ 9.8 1954 _________13.5 2020 _13,6 2020

23 May __ 8.3 1948 _ 8.2 1948 _________13.0 1953 _13.0 1953

24 May __10.1 1891_ 9.4 1891 _________13.1 2017 _13.2 2007

25 May __ 9.8 1899 _10.2 1899,1950 ____14.3 1953 _14.3 1953

26 May __ 8.8 1962 _ 8.9 1962 _________12.9 2019 _13.0 2019

27 May __ 9.5 1984 _ 9.6 1984 _________13.6 1892,2017 _14.0 1892

28 May __10.5 1983_10.3 1923 ________14.1 2001 _14.0 2001

29 May __11.3 1887_11.4 1887,1923 ____13.4 1928 _13.6 1928

30 May __11.2 1975_11.3 1975 ________ 14.6 1944 _14.5 1944

31 May __11.3 1923_11.1 1880 ________ 14.1 1895 _15.1 1895

 

01 Jun __10.4 1964_10.4 1964 _________ 15.3 1947 _15.3 1947

02 Jun __10.6 1964_10.6 1964 _________ 14.6 1947 _14.5 1947

03 Jun __10.5 1923_10.5 1936 _________ 16.4 1947 _16.4 1947

04 Jun __12.3 1923,32,94_12.0 1923 _______ 14.9 1947 _14.9 1947

05 Jun __12.6 1888_12.5 1888,1929 ______15.9 1980 _15.8 1980

06 Jun __10.8 1905_10.7 1985 _________ 15.2 1982 _15.1 1982

07 Jun __11.4 1891_11.5 1891 _________ 14.7 1950 _14.6 1950

08 Jun __10.1 1897_10.5 1897 _________ 15.1 1983 _14.9 1983

09 Jun __11.8 1902_12.0 1902 _________ 14.8 1982 _14.7 1982

10 Jun __11.4 1977_11.3 1977 _________ 14.9 1993 _14.8 1993

11 Jun __11.7 2019_11.6 2019 _________ 15.9 2006 _15.9 2006

12 Jun __12.6 1892_12.7 1892,1902 _____ 15.8 2006 _15.9 2006

13 Jun __12.1 1903_12.0 1903 _________ 15.2 1989 _15.0 1989

14 Jun __10.1 1903_10.5 1903 _________ 13.7 1951 _13.8 1951

15 Jun __12.3 1923_11.9 1903 _________ 14.3 2004 _14.1 1981,2004

16 Jun __12.1 1923_11.7 1923 _________ 14.7 1896 _14.7 1896

17 Jun __12.6 1977_12.5 1977 _________ 14.9 1896 _15.5 2005

18 Jun __12.2 1977_12.1 1977 _________ 15.1 1930 _15.6 2005

19 Jun __12.2 1903_13.2 1903 _________ 15.2 2000,05 _16.2 2005

20 Jun __12.2 1903_12.4 1903 _________ 15.8 2005 _15.4 1936,2005

21 Jun __14.5 1972_14.5 1972 _________ 16.0 1936 _16.1 1936

22 Jun __14.8 1980_14.8 1882 _________ 17.2 1941 _17.3 1941

23 Jun __13.5 1978_13.4 1978 _________ 15.6 1935 _15.6 1935

24 Jun __13.1 1939_13.2 1939 _________ 16.0 1935 _16.1 1935

25 Jun __12.3 1909_12.2 1909 _________ 16.6 1935 _16.6 1935

26 Jun __12.0 1997_12.1 1997 _________ 16.2 2020 _16.3 2020

27 Jun __12.8 1974_12.7 1974 _________ 16.0 1878,2011 _16.0 2011

28 Jun __13.8 2017_13.7 2017 _________ 16.0 1878 _16.1 1878

29 Jun __14.1 1906_14.2 1906 _________ 16.5 1987 _16.3 1987

30 Jun __13.7 1919_14.1 1919 _________ 16.4 1952 _16.4 1952

 

01 Jul __13.9 1919_14.3 1919 _________ 17.1 1968 _17.1 1968

02 Jul __14.7 1912_14.8 1912 _________ 16.9 1952 _17.0 1952

03 Jul __13.5 1907_13.3 1907 _________ 16.5 1999 _16.4 1999

04 Jul __15.0 1879_14.9 1879 _________ 18.0 1976 _17.8 1976

05 Jul __12.5 1920_12.9 1978 _________ 16.4 1976 _16.3 1939,76

06 Jul __13.7 1888_13.8 1888 _________ 16.7 1991,2001 _16.7 2001

07 Jul __13.7 1888_13.7 1888 _________ 16.7 1989 _16.5 1989

08 Jul __14.3 1907_14.2 1907 _________ 16.4 1893 _16.0 1970

09 Jul __13.9 1879_14.1 1879,1948 _____ 16.4 1999 _16.2 1999

10 Jul __15.0 1907,93_15.1 2000 ________16.1 1923 _15,9 2016

11 Jul __13.7 1888_13.4 1888 _________ 16.8 1923 _16.9 1923

12 Jul __13.4 1879_14.0 1879 _________ 17.0 1887 _17.0 1887

13 Jul __14.6 1956_14.6 1956 _________ 17.9 1941 _17.9 1941

14 Jul __14.8 1892_15.5 1988 _________ 16.5 1975 _16.3 1975

15 Jul __14.5 1888_14.6 1888 _________ 16.8 1926 _16.2 1926

16 Jul __14.9 1915,22_15.0 1915 _______ 16.8 2003 _16.6 2003

17 Jul __12.9 1892_13.2 1892 _________ 16.2 2003 _16.0 2003

18 Jul __13.6 1892_13.9 1892 _________ 15.9 1937 _16.3 1878

19 Jul __14.0 1892_14.0 1892 _________ 17.6 1995 _18.9 2022*

20 Jul __14.9 1902_14.8 1902 _________ 19.4 2016 _19.5 2016

21 Jul __13.5 1902_13,5 1902 _________ 15.8 2006 _16.0 2006

22 Jul __13.6 1930_13.9 1930 _________ 17.0 2006 _17.1 2006

23 Jul __13.8 1930_14.1 1930 _________ 17.7 1925 _17.5 1900,25

24 Jul __14.9 1981_14.8 1981 _________ 17.7 2019 _17.9 2019

25 Jul __14.9 1920_15.3 1914,20 ______ 16.2 2019 _16.4 2019

26 Jul __14.9 1920_15.0 1962 _________ 17.8 2006 _18.0 2006

27 Jul __14.9 1886_14.9 1886 _________ 17.2 1949 _17.2 1949

28 Jul __15.3 1888_14,9 1888 _________ 17.0 1947 _17.0 1947

29 Jul __15.2 1898_15.1 1898 _________ 18.8 1948 _18.8 1948

30 Jul __15.4 1898,1965_15.4 1965 _______ 17.5 1911 _16.9 1911

31 Jul __13.8 1912_14.3 1912 _________ 16.5 1995 _17.4 2022*

* V2.0 records in 2022 have no CET legacy equivalents. 19th July 1995 was 17.4 in v2.0. 31st July was 16.3 and other years at 16.5 had taken that record before 2022 broke through. (see also August notes)

 

01 Aug __14.9 1917_14.9 1917 _________ 17.9 1995 _17.8 1995

02 Aug __14.2 1912_13.4 1912 _________ 17.8 1995 _17.7 1995

03 Aug __14.9 1986_15.0 1986 _________ 16.5 1933,95 _17.4 2022* 

04 Aug __15.0 1920_15.3 1920 _________ 17.2 1904 _16.9 1933,94

05 Aug __15.0 1941_15.0 1941 _________ 18.5 1975 _18.5 1975

06 Aug __15.2 1977_15.2 1977 _________ 16.5 2003 _16.6 2003

07 Aug __14.6 1898_14.6 1898 _________ 16.3 2016 _16.5 2016

08 Aug __13.6 1902_14,5 1902 _________ 16.6 1938 _16.7 1938

09 Aug __13.7 1900_14.0 1900 _________ 18.5 2004 _18.5 2004

10 Aug __15.6 1892_15.7 1931 _________ 16.4 2003 _16.4 2003

11 Aug __15.1 1960_15.1 1960 _________ 18.8 1997 _18.8 1997

12 Aug __13.9 1881_14.1 1881 _________ 18.2 2020 _18.5 2020

13 Aug __13.5 1881_13.6 1881 _________ 17.7 2020 _18.0 2020

14 Aug __14.1 1912_14.3 1912 _________ 16.4 2001 _16.7 2001

15 Aug __14.5 1957_14.6 1957 _________ 15.8 1893,2012,13 _16.9 2022*

16 Aug __12.0 1888_13.1 1888 _________ 15.4 1909 _15.5 1926

17 Aug __14.2 1888_14.2 1888 _________ 15.9 2012 _16.1 2012

18 Aug __14.8 1952_14.9 1952 _________ 16.4 1944 _16.4 1944

19 Aug __14.5 1954_14.4 1954 _________ 17.0 1955 _17.0 1955

20 Aug __14.6 1903_14.9 1920 _________ 16.4 1932,97 _16.4 1932

21 Aug __14.7 1944_14.5 1920 _________ 16.5 1997 _16.5 1997

22 Aug __14.3 1904_14.5 1993 _________ 16.5 1997 _16.5 1997

23 Aug __14.5 1979_14.5 1979 _________ 16.3 1997 _16.4 2015

24 Aug __13.8 1931_13.8 1931 _________ 16.4 2003 _18.0 2022*

25 Aug __14.3 1956_14.2 1956 _________ 16.4 1959,95 _16.4 1959,95

26 Aug __12.3 1912_12.7 1912 _________ 15.8 2000 _15.9 2000

27 Aug __13.8 1885_14.3 1885 _________ 15.9 1911 _15.7 1911,30

28 Aug __14.1 1888_14.4 1888 _________ 16.2 1942 _16.2 1942

29 Aug __12.5 1919_12.3 1919 _________ 16.5 1942 _16.4 1942

30 Aug __14.1 1885_14.1 1885 _________ 16.4 2008 _16.6 2008

31 Aug __13.2 1881_13.2 1881 _________ 17.1 1984 _17.1 1984

* V2.0 records in 2022 have no CET legacy equivalents. 3rd Aug 1933 was 16.5 and 1995 was 16.3 in v2.0. 31st July was 16.3 and other years at 16.5 had taken that record before 2022 broke through. For 15th August, 2012 had broken the tie in v2.0 (16.1) before the 2022 record removed it. 24 Aug 2003 was also 16.4 C in v2.0 before that was broken in 2022. 

Edited September 6, 2022 by Roger J Smith

[Roger J Smith]

 

CET low maximum records 1878-2023 _____ CET high minimum records 1878-2023

Date __ CET leg _ CET v2.0 _____________ CET leg _ CET v2.0 _______________

01 Sep __13.3 1881 _13.5 1881 ________ 16.4 1984 __ 16.4 1984

02 Sep __13.5 1915 _14.2 1915 ________ 16.3 1939 __ 16.3 1939

03 Sep __11.7 1908 _11.9 1908 ________ 16.5 1939 __ 16.6 1939

04 Sep __12.2 1908 _12.4 1908 ________ 14.7 1973 __ 15.4 2022*

05 Sep __12.7 1931 _12.7 1931 ________ 18.4 1949 __ 18.4 1949

06 Sep __13.0 1952 _13.0 1952 ________ 16.1 1898,1958_ 16.2 1898

07 Sep __12.5 1952 _11.9 1952 ________ 16.2 2016 __ 17.7 2023*

08 Sep __12.3 1909 _12.2 1909 ________ 15.9 2009 __ 16.0 1898,2009

09 Sep __12.5 1952 _12.6 1912,52,72 ___ 15.4 2021 __ 16.6 2023* 15.5 2021

10 Sep __12.9 1912 _12.2 1912 ________ 15.9 2011 __ 16.1 2023* 16.0 2011

11 Sep __11.4 1912 _11.7 1912 ________ 15.8 2021 __ 15.9 2021

12 Sep __13.1 1948 _12.9 1922 ________ 17.3 1945 __ 17.2 1945

13 Sep __12.6 1909 _12.6 1909 ________ 15.9 2006 __ 16.0 2006

14 Sep __12.0 1975 _11.8 1975 ________ 16.1 2016 __ 16.2 2016

15 Sep __11.4 1994 _11.4 1994 ________ 14.6 1932 __ 14.5 1947

16 Sep __13.0 1976 _12.9 1976 ________ 16.1 1961 __ 16.1 1961

17 Sep __11.8 2013 _11.8 2013 ________ 15.4 1926 __ 15.0 1926,45

18 Sep __11.1 1952 _11.2 1952 ________ 14.9 1945 __ 14.9 1945

19 Sep __12.1 1912 _11.7 1919 ________ 14.8  2014 __ 15.0 2014

20 Sep __11.6 1977 _11.5 1977 ________ 15.9 1947 __ 15.8 1947

21 Sep __11.5 1948 _11.5 1948 ________ 15.7 2006 __ 15.8 2006

22 Sep __11.8 1948 _11.7 1889 ________ 14.8 1989 __ 14.7 2006

23 Sep __11.0 1893 _11.1 1893 ________ 15.1 1956 __ 15.1 1956

24 Sep __11.9 1889 _12.2 1972,2010 ____ 14.9 2006 __ 15.0 2006

25 Sep __12.2 1885,88_11.9 1888 _______ 14.6 1895 __ 14.5 1936

26 Sep __10.7 1926 _10.6 1926 ________ 14.1  1976 __ 14.1 1967

27 Sep __ 9.8 1974 __ 9.6 1974 ________ 14.2 1913,41_ 14.6 1913

28 Sep __11.1 1974 _10.9 1974 ________ 15.0 1948 __ 15.0 1948

29 Sep __ 8.3 1918 __ 8.2 1918 ________ 15.7 1908 __ 15.4 1908

30 Sep __10.1 1918 _10.1 1918 ________ 14.8 1908 __ 14.8 1923

* 4 Sep 1973 was also 14.7 in v2.0, broken by 15.4 in 2022. 

* 7 Sep 2016 at 16.3 in v2.0, broken by 17.7 in 2023. 

(8 Sep 2023 at 15.4 failed to break existing record)

* 9 Sep 2021 at 15.5 in v2.0, broken by 16.6 in 2023. 

*10 Sep 2011 at 16.0 in v2.0, broken by 16.1 in 2023.

01 Oct __10.3 1888 _10.3 1888 _________ 14.8 1985 __ 14.6 1985 

02 Oct __ 7.9 1888 __7.6 1888 __________ 13.8 1954 __ 13.8 1954

03 Oct __ 8.5 1923 __8.5 1923 __________ 15.4 2011 __ 15.3 2011

04 Oct __ 8.4 1880 __8.1 1880 __________ 15.0  2013 __ 14.9 2013

05 Oct __ 9.6 1888 __9.7 1888 __________ 14.1 1886 __ 14.2 1886

06 Oct __ 8.6 1888 __8.6 1888 __________ 13.8 1990 __ 13.7 1990

07 Oct __ 9.9 1904 __9.9 1888 __________ 13.8 1878 __ 13.7 1900

08 Oct __10.1 1892 _10.2 1881,92 _______ 13.2 1969 __ 13.2 1969,2005

09 Oct __ 8.8 1887 __8.7 1887 __________ 14.7 1967 __ 14.7 1967

10 Oct __ 8.2 1980 __7.9 1980 __________ 14.4 1921,2011_14.3 1921,2011 

11 Oct __ 6.0 1896 __6.1 1896 __________ 14.2 2011 __ 14.6 2005

12 Oct __ 7.4 1887 __7.2 1887 __________ 15.2 2005 __ 15.1 2005

13 Oct __ 8.0 1971 __8.0 1971 __________ 15.1 2018 __ 14.9 2018

14 Oct __ 8.8 1925 __8.7 1925 __________ 15.2 2017 __ 15.1 2017

15 Oct __ 7.6 1879 __7.6 1879 __________ 14.2 1893 __ 14.2 1893

16 Oct __ 7.8 1905,80_7.5 1980 __________ 13.1 1954 __ 13.1 1954

17 Oct __ 7.7 1905 __7.8 1905 __________ 13.0 1897 __ 12.9 1897

18 Oct __ 7.8 1926 __7.8 1926 __________ 14.7 2014 __ 14.5 2014

19 Oct __ 6.9 1896 __7.1 1896 __________ 14.1 2014 __ 14.0 2014

20 Oct __ 5.4 1880 __5.3 1880 __________ 12.2 1941 __ 12.2 1941

21 Oct __ 6.3 1926 __6.1 1926 __________ 13.1 2020 __ 13.0 2020

22 Oct __ 5.7 1895 __5.6 1895 __________ 13.7 1906 __ 13.5 1906

23 Oct __ 6.2 1895 __6.3 1895 __________ 12.8 1998 __ 12.6 1998

24 Oct __ 6.2 1895,1926_6.3 1926 ________ 11.6 2012 __ 11.4 2012

25 Oct __ 5.9 1892 __6.0 1892 __________ 12.1 1978 __ 11.9 1978

26 Oct __ 5.9 1880,95_5.2 1895 __________ 13.3 1927 __ 13.5 1927

27 Oct __ 5.4 1895 __5.8 1895 __________ 14.6 1888 __ 14.5 1888

28 Oct __ 5.6 1895 __5.4 1926 __________ 13.7 1888 __ 13.8 2022*

29 Oct __ 4.6 1895 __4.7 1895 __________ 13.2 1935 __ 13.2 1935

30 Oct __ 5.6 1881 __5.5 1974 __________ 13.2 2005 __ 13.1 2005

31 Oct __ 3.1 1934 __3.6 1934 __________ 13.1 2014 __ 13.0 2014

* in v2.0, broke 13.5 from 2005

 

01 Nov __ 3.3 1881 __3.5 1881 _________ 12.0 1894 __ 12.2 1894

02 Nov __ 5.0 1880 __4.9 1880 _________ 12.5 1894 __ 12.5 1894

03 Nov __ 5.1 1922 __4.7 1919 _________ 13.5 1996 __ 13.4 1996

04 Nov __ 3.4 1919 __3.7 1919 _________ 12.8 1931 __ 12.8 1931

05 Nov __ 3.0 1901 __3.0 1901 _________ 13.2  1938 __ 13.3 1938

06 Nov __ 5.8 1901 __5.7 1901 _________ 12.3  2015 __ 12.2 2015

07 Nov __ 3.6 1888 __3.6 1888 _________ 11.4 1972,2015_ 11.4 1972,2015 

08 Nov __ 3.4 1921 __3.5 1921 _________ 10.4 1938 __ 10.4 1938,1939

09 Nov __ 4.5 1919,21_ 4.8 1971 ________ 10.7 1994 __ 10.5 1994

10 Nov __ 3.8 1919 __3.7 1919 _________ 10.6 1977 __ 10.4 1977,2015

11 Nov __ 3.1 1919 __3.2 1919 _________ 12.7 2015 __ 12.7 2015, 2022

12 Nov __ 2.4 1919 __2.3 1919 _________ 12.4 1947 __ 12.4 1947

13 Nov __ 1.4 1919 __1.9 1919 _________ 13.1 1938 __ 13.3 1938

14 Nov __ 1.7 1919 __1.9 1919 _________ 12.1 1938 __ 12.1 1938

15 Nov __ 0.5 1965 __0.5 1965 _________ 11.3 1948 __ 11.3 1948

16 Nov __ 0.6 1901 __1.2 1901 _________ 11.4 1997 __ 11.1 1997

17 Nov __ 2.7 1930 __3.1 1930 _________ 11.3 1997 __ 11.0 1997

18 Nov __ 0.7 1887 __1.3 1887 _________ 11.3 2020 __ 11.3 2020

19 Nov __ 2.0 1902 __1.8 1902 _________ 12.0 1978 __ 11.8 1978

20 Nov __ 2.5 1962 __2.6 1962 _________ 12.0 1994 __ 11.7 1994

21 Nov __ 1.1 1880 __1.0 1880 _________ 11.7 1947 __ 11.7 1947

22 Nov __ 2.1 1880,1920_2.0 1880 ________13.5 1947 __ 13.5 1947

23 Nov __-0.5 1993 __-0.6 1993 _________12.3 1947 __ 12.3 1947

24 Nov __-0.3 1904 __ 0.8 1904 _________ 11.4 1980 __ 11.2 1980

25 Nov __ 2.3 2010 __2.2 1904,23,2010 ____ 11.1 1964 __ 11.1 1964

26 Nov __1.2 1904 __1.3 1904 __________ 11.3 1983 __ 11.2 1983

27 Nov __-0.3 1890 __-0.5 1890 __________ 9.0 1994 _ 8.8 1994,2022

28 Nov __-1.0  2010 __-1.0 2010 ________ 10.2 1917 __ 10.1 1953

29 Nov __ 0.0 1890 __ 0.2 1890 _________ 10.6 2000 __ 10.4 2000

30 Nov __ 0.4  1973 __0.5 1973 _________ 10.8 1939 __ 10.9 1939

 

01 Dec __-0.4 2010 __-0.4 2010 _________ 10.6 1939 __ 10.5 1939

02 Dec __-1.2 1879 __-1.2 1879 __________ 9.9 1985 ___ 9.7 1985

03 Dec __-0.4 1879 __-0.6 1879 _________ 11.2 1985 __ 11.1 1985

04 Dec __-1.5 1925 __-1.4 1925 _________ 10.6 1934 __ 10.6 1934

05 Dec __-0.6 1902 __-0.4 1902 _________ 11.3 1898 __ 11.4 1898

06 Dec __-1.8 2010 __-1.8 2010 _________ 10.8 1898 __ 10.6 1898

07 Dec __-0.4 2010 __-0.4 2010 __________ 9.5 1964 ___ 9.6 1964

08 Dec __-0.7 1967 __-0.7 1967 _________ 10.6 2015 __ 10.4 2015

09 Dec __ 0.8 1981 __ 0.6 1981 _________ 11.2 1934 __ 11.1 1934

10 Dec __-1.2 1981 __-1.5 1981 __________ 9.7 2016 ___ 9.6 2016 

11 Dec __-0.8 1882 __-1.5 1882 _________ 10.8 1994 __ 10.5 1994

12 Dec __-3.8 1981 __-4.0 1981 _________ 11.9 1994 __ 11.6 1994

13 Dec __-1.9 1920 __-1.3 1878,1920 _____ 10.8 1994 __ 10.6 1994

14 Dec __-2.2 1878 __-2.4 1878 _________ 10.5 2006 __ 10.4 2006

15 Dec __-0.3 1890 __ 0.4 1890,1950 ______ 9.8 1985 ___ 9.6 1985 

16 Dec __-0.3 1890 __-0.2 1981 __________ 9.1 1985 ___ 8.9 1985

17 Dec __-0.5 1981 __-0.7 1981 _________ 11.0 2015 __ 10.8 2015

18 Dec __-1.3 1927 __-1.2 1927 _________ 10.5 1932 __ 10.4 1932

19 Dec __-3.2 2010 __-3.2 2010 _________ 10.8 2015 __ 10.7 2015

20 Dec __-2.2 1938 __-2.1 1938 __________ 9.6 2015 ___ 9.5 2015 

21 Dec __-1.5 1891 __-1.4 1891 __________ 9.6 1971 ___ 9.6 1971 

22 Dec __-1.5 1891 __-2.2 1891 _________ 10.0 1991 ___ 9.8 1991 

23 Dec __-2.7 1891 __-4.0 1891 _________ 11.1 1991 __ 10.8 1991

24 Dec __-1.8 1891 __-1.4 1878 __________ 8.7 2002 ___ 9.3 2023*  

25 Dec __-2.6 2010 __-2.5 2010 __________ 9.3 1983 ___10.1 2023*

26 Dec __-0.8 1906 __ 0.0 1906 __________ 9.7 2011 ___ 9.6 2011 

27 Dec __-0.9 1899 __-0.7 1892 __________ 8.7 1949 ___ 8.7 1949   

28 Dec __-3.0 1995 __-3.1 1995 _________ 10.2 1987 ___ 9.9 1987

29 Dec __-4.0 1908 __-4.5 1908 _________ 10.9 1987 __ 10.8 1987

30 Dec __-1.7 1890 __-1.8 1890 __________ 9.1 1925 ___ 8.9 1925  

31 Dec __-2.4 1978 __-2.6 1978 _________ 11.8 2021 __ 11.7 2021

* 24 Dec 9.3 (2023) replaced 8.9 (1977) in v2.0. 2002 (legacy record) was 8.6 in v2.0. 

*25 Dec 10.3 (2023) replaced 9.1 (1983) in v2.0. 

 

 

Edited December 26, 2023 by Roger J Smith
new records 24, 25 Dec (9.3 C) (10.1 C)

[Roger J Smith]

Bumping this thread which I have been editing as we continue to set new (v2.0) records, in the latest cold spell, 15th and 16th have set new daily minima and replaced two values (1878, 1899) which had not been changed very much from CET legacy. The max on the 15th (0.5) just missed a tied value of 0.4 (1890, 1950) which had been revised up from a previous -0.3 (1890 alone) in legacy.

Daily means while impressive have not broken older records (daily means (1772-2022) go back beyond the era of max and min which is 1878-2022). The 16th to 18th of 1859 had means around -7 C so from that you could infer that the minima might have been -10 to -12. 

[Roger J Smith]

On April 18, 2023, the v2.0 data set stopped updating and v2.0.1.0 replaced it. No announcement was made as to why and I assumed it was just a renaming, but apparently there are a few changes from v2.0 to v2.0.1.0 after all. I discovered this today when I was posting a contest thread for July. A check of the two data sets shows that a few months have a new mean by 0.1, but at the same time, no daily data appear to have changed (I have not exhaustively checked that assumption yet). My conclusion is that a different rounding protocol was introduced and it caused a few monthly means to go up or down by 0.1 ... possibly just a different view on which way to go from certain data points, or perhaps a change in procedure (if you round daily means, you get a different result than if you average the mean max and mean min). Anyway, from 1981 to present, here are the two data sets of monthly means in which I have highlighted the changed values in bold type. 

First v2.0.1.0 and after that v2.0.

(v2.0.1.0) _______________________________________________________ (v2.0) ________________________________________________________

1981 4.8 3.0 7.8  7.8 11.2 13.1 15.5 16.3 14.4  8.3 7.6 0.1  9.2 ... 1981 4.8 3.0 7.9  7.8 11.2 13.1 15.5 16.3 14.4  8.3 7.6 0.1  9.2

1982 2.7 4.8 6.0  8.6 11.6 15.5 16.4 15.7 14.1  9.9 7.7 4.1  9.8 ... 1982 2.7 4.8 6.0  8.6 11.6 15.5 16.4 15.7 14.1  9.9 7.7 4.1  9.8

1983 6.7 1.8 6.4  6.8 10.3 14.3 19.4 17.4 13.7 10.3 7.4 5.4 10.1 ..1983 6.7 1.8 6.4  6.8 10.3 14.3 19.4 17.4 13.7 10.3 7.4 5.4 10.1

1984 3.9 3.5 4.7  8.1   9.9 14.4 16.8 17.7 13.6 11.0 7.8 5.1  9.7 ...1984 3.9 3.4 4.7  8.1   9.9 14.3 16.8 17.7 13.6 11.0 7.8 5.1  9.7

1985 0.9 2.2 4.7  8.3 10.9 12.6 16.1 14.7 14.6 10.8 3.9 6.2  8.9 ...1985 0.9 2.2 4.7  8.3 10.9 12.6 16.1 14.7 14.6 10.8 3.9 6.1  8.9

1986 3.5 -1.0 5.0 5.8 11.0 14.6 15.7 13.7 11.3 10.8 7.6 6.1 8.7 ...1986 3.5 -1.0 5.0  5.8 11.0 14.7 15.7 13.7 11.3 10.8 7.6 6.1 8.7

1987 0.8 3.6 4.1 10.3 10.1 12.7 15.8 15.6 13.6  9.6 6.4 5.4  9.0 ...1987 0.8 3.6 4.1 10.3 10.1 12.7 15.8 15.6 13.6 9.5 6.3 5.4  9.0

1988 5.3 4.9 6.4  8.2 11.9 14.2 14.6 15.2 13.2 10.3 5.0 7.3 9.7 ... 1988 5.3 4.9 6.4  8.2 11.9 14.2 14.6 15.2 13.2 10.3 5.0 7.3  9.7

1989 6.1 6.0 7.5  6.6 12.9 14.4 18.1 16.6 14.6 11.5 6.0 4.7 10.4 .. 1989 6.1 6.0 7.5  6.6 12.9 14.4 18.1 16.6 14.6 11.5 6.0 4.7 10.4

1990 6.5 7.3 8.3  8.0 12.6 13.5 16.8 18.0 13.2 11.7 6.7 4.1 10.6 .. 1990 6.5 7.3 8.3  8.0 12.6 13.5 16.8 18.0 13.2 11.7 6.7 4.1 10.6

1991 3.2 1.6 7.8  7.9 10.7 11.9 17.1 17.1 14.6 10.0 6.6 4.5  9.5 ... 1991 3.2 1.6 7.8  7.9 10.7 11.9 17.1 17.1 14.6 10.0 6.6 4.5  9.5

1992 3.6 5.4 7.5  8.7 13.6 15.7 16.1 15.3 13.3   7.7 7.2 3.4  9.8 ... 1992 3.6 5.4 7.5  8.7 13.6 15.7 16.1 15.3 13.3   7.7 7.2 3.4  9.8

1993 5.9 4.7 6.6  9.4 11.5 15.0 15.1 14.6 12.3   8.3 4.5 5.3  9.5 ... 1993 5.9 4.7 6.6  9.4 11.5  15.0 15.1 14.6 12.3   8.3 4.5 5.3  9.5

1994 5.3 3.2 7.6  8.0 10.7 14.4 18.0 16.0 12.7 10.0 9.9 6.2 10.2 .. 1994 5.3 3.2 7.6  8.0 10.7 14.4 18.0 16.0 12.7 10.0 9.9 6.2 10.2

1995 4.8 6.5 5.5  9.1 11.6 14.2 18.5 19.1 13.6 12.7 7.5 2.1 10.5 .. 1995 4.8 6.5 5.5  9.1 11.6 14.2 18.5 19.1 13.6 12.8 7.5 2.1 10.5

1996 4.3 2.5 4.5  8.5   9.2 14.4 16.4 16.6 13.6 11.5 5.7 2.7  9.2 ... 1996 4.3 2.5 4.5  8.6   9.2 14.4 16.4 16.6 13.6 11.5 5.7 2.7   9.2

1997 2.4 6.7 8.4  9.0 11.5 14.0 16.6 19.0 14.2 10.0 8.2 5.7 10.5 .. 1997 2.4 6.7 8.3  9.0 11.5 14.0 16.6 19.0 14.2 10.0 8.2 5.7 10.5

1998 5.1 7.2 7.8  7.7 13.1 14.1 15.4 16.0 14.8 10.4 6.0 5.4 10.3 .. 1998 5.1 7.2 7.8  7.7 13.1 14.1 15.4 16.0 14.8 10.4 6.0 5.4 10.3

1999 5.5 5.3 7.3  9.5 12.9 13.8 17.6 16.2 15.6 10.6 7.7 4.8 10.6 .. 1999 5.5 5.3 7.3  9.4 12.9 13.8 17.5 16.2 15.6 10.6 7.7 4.8 10.6

2000 4.8 6.2 7.5  7.7 12.0 14.9 15.3 16.7 14.8 10.2 6.8 5.4 10.2 .. 2000 4.9 6.2 7.5  7.7 12.1 14.9 15.3 16.7 14.7 10.2 6.8 5.3 10.2

2001 3.2 4.3 5.2  7.7 12.5 14.2 17.1 16.8 13.4 13.2 7.5 3.4  9.9 ... 2001 3.2 4.3 5.2  7.7 12.5 14.2 17.1 16.8 13.4 13.2 7.5 3.4  9.9

2002 5.5 7.0 7.6  9.3 11.8 14.3 15.8 17.0 14.4 10.0 8.4 5.6 10.6 .. 2002 5.5 7.0 7.6  9.3 11.8 14.3 15.8 17.0 14.4 10.0 8.4 5.6 10.6

2003 4.4 3.9 7.5  9.6 12.0 15.9 17.4 18.3 14.3  9.1  8.0 4.6 10.5 .. 2003 4.5 3.9 7.5  9.6 12.0 15.9 17.4 18.3 14.3  9.1  8.0 4.6 10.5

2004 5.2 5.4 6.5  9.4 12.1 15.3 15.7 17.6 14.9 10.4 7.6 5.3 10.5 .. 2004 5.2 5.4 6.5  9.4 12.1 15.2 15.7 17.6 14.9 10.4 7.6 5.3 10.5

2005 5.9 4.3 7.1  8.9 11.3 15.8 16.8 16.2 15.2 13.0 6.1 4.3 10.5 .. 2005 5.9 4.3 7.1  8.9 11.3 15.8 16.8 16.2 15.2 13.0 6.1 4.3 10.5

2006 4.4 3.9 5.0  8.7 12.3 15.8 19.8 16.2 16.9 12.9 8.0 6.4 10.9 .. 2006 4.4 3.9 5.0  8.6 12.3 15.8 19.8 16.2 16.8 12.9 8.0 6.4 10.9

2007 7.0 6.0 7.3 11.3 11.9 15.1 15.3 15.5 13.9 10.7 7.2 4.9 10.5 .. 2007 7.0 5.9 7.3 11.2 11.9 15.1 15.3 15.5 13.9 10.7 7.2 4.9 10.5

2008 6.7 5.6 6.1  8.0 13.4 13.9 16.4 16.3 13.5  9.5 7.0 3.5  10.0 ... 2008 6.6 5.6 6.1 8.0 13.4 13.9 16.4 16.3 13.5  9.6 7.0 3.5  10.0

2009 3.1 4.3 7.1 10.1 12.1 14.7 16.3 16.7 14.3 11.4 8.6 3.1 10.2 .. 2009 3.1 4.3 7.1 10.0 12.1 14.7 16.3 16.7 14.3 11.4 8.6 3.0 10.2

2010 1.5 2.9 6.2  8.9 10.7 15.2 17.2 15.4 13.8 10.2 5.1 -0.7  8.9 ... 2010 1.5 2.9 6.2  8.9 10.7 15.2 17.2 15.4 13.8 10.2 5.1 -0.7  8.9

2011 3.8 6.5 6.8 11.9 12.2 13.7 15.3 15.5 15.1 12.5 9.5 5.9 10.7 .. 2011 3.7 6.5 6.8 11.9 12.2 13.7 15.3 15.5 15.1 12.5 9.5 5.9 10.7

2012 5.5 4.0 8.4  7.3 11.8 13.5 15.6 16.7 13.0  9.5  6.8 4.7  9.8 ... 2012 5.5 4.0 8.3  7.3 11.8 13.5 15.6 16.7 13.0  9.5 6.8 4.7  9.8

2013 3.5 3.4 2.8 7.6 10.5 13.6 18.4 17.0 13.7 12.4  6.1 6.3  9.6 ... 2013 3.5 3.3 2.8  7.5 10.5 13.6 18.5 17.0 13.7 12.4 6.1 6.3 9.6

2014 5.8 6.3 7.7 10.3 12.3 15.1 17.8 15.1 15.1 12.3 8.5 5.1 11.0 .. 2014 5.7 6.3 7.7 10.3 12.3 15.1 17.9 15.1 15.1 12.3 8.5 5.1 11.0

2015 4.5 4.2 6.5  9.1 10.8 13.9 16.0 16.0 12.7 10.9 9.4 9.6 10.3 ... 2015 4.5 4.2 6.5  9.1  10.8 13.9 16.0 16.0 12.7 10.9 9.4 9.6 10.3

2016 5.5 5.1 5.8  7.5 12.6 15.2 17.0 17.1 16.1 10.7 5.5 5.9 10.4 ... 2016 5.5 5.1 5.8  7.5  12.6 15.2 17.0 17.1 16.1 10.7 5.5 5.9 10.4

2017 4.0 6.2 8.8  9.0 13.3 16.0 16.9 15.7 13.6 12.2 6.8 4.7 10.6 ... 2017 4.0 6.2 8.8  8.9  13.3 16.0 16.9 15.7 13.6 12.2 6.8 4.7 10.6

2018 5.3 3.1 5.0  9.9 13.3 16.1 19.2 16.8 13.7 10.5 8.3 6.8 10.7 ... 2018 5.3 3.1 5.0  9.9  13.3 16.1 19.3 16.8 13.7 10.5 8.3 6.8 10.7

2019 4.0 6.9 7.9  9.2 11.2 14.2 17.6 17.2 14.3  9.8  6.2 5.7 10.4 ... 2019 4.0 6.9 7.9  9.1  11.2 14.2 17.6 17.2 14.3  9.8  6.2 5.7 10.4

2020 6.4 6.5 6.8 10.5 12.5 15.3 15.8 17.7 14.0 10.4 8.5 4.9 10.8 .. 2020 6.4 6.4 6.8 10.5 12.6 15.3 15.8 17.7 14.0 10.4 8.5 4.9 10.8

2021 3.2 5.3 7.3  6.5 10.2 15.5 17.8 16.0 16.0 12.0 7.2 6.3 10.3 ... 2021 3.2 5.3 7.3  6.5  10.3 15.5 17.8 16.0 16.0 12.0 7.2 6.3 10.3

2022 4.7 6.9 8.0  9.2 13.1 14.9 18.2 18.7 14.4 12.8 9.2 3.4 11.1 ... 2022 4.7 6.9 8.0  9.2  13.1 14.9 18.2 18.7 14.4 12.8 9.2 3.4 11.1

2023 5.2 6.5 7.0  8.7 12.5 _________________________________________2023 5.2 6.5 7.0 (v2.0 discontinued)

_________________________________________

So in the past most recent 42 years I found 38 months that have changed by 0.1, 25 went up and 13 went down. 

I am guessing there will be similar numbers of changes in all data at least through the daily period, if I find none 1772-1877 that will indicate the source is probably daily max and min averages (those are not available 1772-1877). If I find there are some before 1772 it will be more of a mystery, v2.0 just copied legacy values but did create some new monthly means before daily data and I assumed those were from rounding protocols being changed. 

Will report in less detail on the other monthly changes that I find v2.0.1.0 compared to v2.0. 

There was a random distribution of what rankings were altered, you'll note one change is to warmest September 2006 which added 0.1 to become 16.9 now. Some other top ten months were altered as well. Other changes are to middle of the pack months. Odd that 2000 has four changes while the interval 1988 to 1994 required no changes at all. 

 

[Roger J Smith]

After a complete comparison and check I found the following:

(a) No differences were found 1659 to 1946.

(b) Fewer differences appeared before 1975, with a similar rate from 1975 to 1980 as shown in my previous post.

This is the full list of changes found ... note that changes to annual means in 1947 and 1960 were not accompanied by any changes to monthly means.

(conclusion is that these changes are all due to some kind of rounding protocols that was probably being used before 1960 or 1947 (otherwise you would expect to find more changes before then ... the only other possibility if daily data are not being adjusted would be that work is underway and proceeding backwards in time, and I happened to notice it before it was competed, so will check back in a few weeks to see if there are still no changes before 1947).

 

ADDITIONAL ADJUSTMENTS TO DATA IN v2.0.1.0 (compared to v2.0)

 

__ v2.0.1.0 _______________________________________________________ v2.0 _________________________________________________

1947 2.2 -1.9 3.6 8.6 13.5 15.5 17.0 18.6 14.9 10.6 7.2 5.1 9.6 ... 1947 2.2 -1.9 3.6 8.6 13.5 15.5 17.0 18.6 14.9 10.6 7.2 5.1 9.7

1960 3.8 4.1 6.4  8.9 12.8 16.1 15.1 15.0 13.1 10.3 7.3 3.9 9.7 ... 1960 3.8 4.1 6.4  8.9 12.8 16.1 15.1 15.0 13.1 10.3 7.3 3.9 9.8

1968 4.4 1.9 6.3 8.1  9.8 14.8 15.0 15.4 13.9 12.5 6.5 3.0 9.3 ... 1968 4.5 1.9 6.3 8.1   9.8 14.8 15.0 15.4 13.9 12.5 6.5 3.0 9.3

1975 6.8 4.5 4.8 8.3 9.8 14.6 17.3 18.6 13.4 9.7 6.1 5.0 10.0 ... 1975 6.8 4.5 4.8 8.3 9.8 14.6 17.3 18.6 13.4 9.7 6.0 5.0 9.9

1976 5.9 4.6 4.8 8.1 12.0 16.9 18.6 17.6 13.3 10.4 6.0 1.8 10.0 . 1976 5.9 4.6 4.8 8.1 12.0 16.9 18.5 17.6 13.3 10.4 6.0 1.8 10.0

1977 2.8 5.2 6.8 7.2 10.6 12.1 15.7 15.2 13.2 11.5 6.4 5.9 9.4 .. 1977 2.7 5.2 6.8 7.2 10.6 12.1 15.8 15.2 13.2 11.5 6.4 5.9 9.4

1978 3.3 2.8 6.7 6.5 11.6 13.5 14.7 15.0 14.1 11.7 8.3 3.7 9.4 .. 1978 3.3 2.8 6.7 6.5 11.7 13.5 14.7 15.0 14.1 11.7 8.3 3.7 9.4

1979 -0.4 1.3 4.7 7.7 9.9 13.8 16.0 14.9 13.3 11.1 6.6 5.6 8.7 ... 1979 -0.4 1.2 4.7 7.7 9.9 13.8 16.0 14.9 13.3 11.1 6.6 5.6 8.7

 

 

 

[Alex Starling]

Hello everyone - I've been a regular user of netweather for years for info gathering, but am newbie registered now as I recently found out about this topic (HADCET adjustment) and came across this thread.  Thanks for all the useful comments above. I have seen a number of people plot the changes in a linear fashion, but I found it helpful to plot things in a heatmap (done below for the mean).

All I can say is that that's an odd set of adjustments. Feb, July and August get the majority of the post 2006 upgrades; June essentially untouched, apart from one of the biggest upgrades in 2005. Last three months of the year get the heavy downgrades 1974 through to 2000. The wobbles start suddenly in 1974 (what did the three day week effects anyone?!!)...

As others have pointed out, Zero adjustments between 1917 and 1967. Then nine adjustments between 1853 and 1916 Then nothing back to 1659 except for five trivial tweaks 1788 to 1798.

Spreadsheet available if anyone wants to cross-check.

I'd welcome any comments or suggestions for further research. 

[Roger J Smith]

Alex, thanks for that, it does match what we were discussing earlier and as you say there is no intuitively obvious reason why some months would show increases, others would show flat line results, within the same years. They do go into some detail about why years like 2000 and 2005 show larger changes than many others, in a document you can access on their site posted when v2.0 came out. Without going back and re-reading it, I think it had to do with a re-assessment of adjustments made when station locations changed around then. June 2005 got a bigger boost than most months mainly due to increases around hot weather mid-month. December 2000 got a larger decrease mainly due to colder values introduced for the late month cold spell. As to why they did that, I imagine it was a re-assessment of how location A used in those months can be or should be compared to location B that came into operation in the CET average at another time.

As far as I can determine v2.0.1.0 is mostly about rounding monthly means in cases near boundaries in two decimals and has no actual daily data changes involved in it, just calculation changes. As you see, I provide a list of the months with 0.1 rounding changes both up and down, and it includes a couple of annual means too. I just regard it as white noise since there are almost equal numbers of increases and decreases. 

One theory, maybe they came up with different trends for months based on some fine tuning of their urban heat island adjustment protocol. Maybe it was decided that the 0.2 decrease was okay in the months that have stayed similar, but needed to be reduced in the months that have warmed, or increased in the months that have cooled in their data adjustments. If they said, "let's reduce that adjustment from February to August, leave June and September alone, and increase the adjustment in October to December" that would explain what we're seeing in your table and our earlier discussions, since 2005. I don't know when they went to the 0.2 adjustment, presumably there was an interval with an adjustment of 0.1 and an earlier period with no adjustment? I do know there were station changes of some importance around 2000 to 2005 and that might have brought on the urban heat island adjustment in the first place. Perhaps the CET locations were considered pristine rural settings before 2000. 

[Midlands Ice Age]

On 11/07/2023 at 10:40, Alex Starling said:

Hello everyone - I've been a regular user of netweather for years for info gathering, but am newbie registered now as I recently found out about this topic (HADCET adjustment) and came across this thread.  Thanks for all the useful comments above. I have seen a number of people plot the changes in a linear fashion, but I found it helpful to plot things in a heatmap (done below for the mean).

All I can say is that that's an odd set of adjustments. Feb, July and August get the majority of the post 2006 upgrades; June essentially untouched, apart from one of the biggest upgrades in 2005. Last three months of the year get the heavy downgrades 1974 through to 2000. The wobbles start suddenly in 1974 (what did the three day week effects anyone?!!)...

As others have pointed out, Zero adjustments between 1917 and 1967. Then nine adjustments between 1853 and 1916 Then nothing back to 1659 except for five trivial tweaks 1788 to 1798.

Spreadsheet available if anyone wants to cross-check.

I'd welcome any comments or suggestions for further research. 

Alex..

Welcome.

A very good 'find' I think.

Worth more investigation as on the face of it, it seems to have the effect of decreasing the pre 1970 data, but increasing the warming since. 

MIA 

[Roger J Smith]

The twelve coldest CET daily minima for Nov ... all but four are daily records (27 Nov 1904, 17 Nov 1930, 25 Nov 1952 are all second coldest values for date and 27 Nov 1915 is third coldest) ... can we join this exclusive club tonight? 

 1. __ -7.8 __ 24 Nov 1904

 2. __ -7.0 __ 28 Nov 2010

 3. __ -6.8 __ 23 Nov 1983

t4. __ -6.3 __ 27 Nov 1923

t4. __ -6.3 __ 29 Nov 2010

t6. __ -6.1 __ 17 Nov 1901

t6. __ -6.1 __ 27 Nov 1904

 8. __ -5.9 __ 25 Nov 1923

t9. _ -5.8 ___ 16 Nov 1901

t9. _ -5.8 ___ 17 Nov 1930

t9. _ -5.8 ___ 27 Nov 1915 

(CET legacy _ -5.8 _ 30 Nov 1919 was revised to -5.5 in v2.0)

12. __-5.7 ___25 Nov 1952

(note 23 Nov 1858 before daily minima records begin was very likely in this range as daily mean was -3.9 C).

 

 

Edited November 29, 2023 by Roger J Smith

[Roger J Smith]

I mentioned back in the thread an error in CET data base where max was lower than min for 23 Dec 1884.

This was resolved in v2.0.1.0, I just noticed it today and also found a new product on site explaining a few things about that and other issues. Look for the "release notes" link on the CET home page. 

Apparently at one location (Ross-on-Wye) used in original research on CET years ago, a notation of +5.1 was read as -15.1, no doubt handwriting issue in old tables consulted back when CET was first developed (as the old notes were likely in F deg, I don't know what looked like what, it would be about 5 F looking like 41 F). This error persisted all through the years, I brought it to their attention along with the EWP truncation errors already discussed and resolved earlier. The reason I noticed it was that in my excel file, I was studying daily ranges and ran a program to find the largest and smallest ones. To my surprise 23 Dec 1884 was a negative range (max lower than min). I knew that had to be wrong. So the reason was discovered and now we have corrected data for 23 Dec 1884 (max of -2.4 was adjusted to 4.6). They mention in the release notes making a few other small adjustments but except for those, about 99.9% of v2.0.1.0 daily data continue on from v2.0 data.