December 2021 C.E.T. and EWP forecast contests -- start of the new contest year for 2021-2022

[The PIT]

20 hours ago, Roger J Smith said:

Sorry, you were maybe clearer than I thought, the reason then is probably that the PIT is in an urban area and the CET average is adjusted down somewhat to remove urban effects. The PIT is reporting vs end of month average so the differential may get even larger as the CET report is against a running mean 1st to 20th at present. Also maybe the PIT will let us know this, but his "normal" could be 1991-2020 rather than 1981-2010 which would make it warmer. But I think it's mostly the urban setting that accounts for the difference, which as you say should probably be running in the other direction. 

 

I'm using  1991- 2020 and also a sort of guestimate method as too how the temperature falls through the month.

[Roger J Smith]

Almanac for 23rd December

 

The highest daily mean (1772-2020) was 11.8 in 1991 which replaced 11.4 from 1843. Other mild averages were 11.3 in 1977, 10.9 in 2014, 10.6 in 1980, 10.3 in 1974, 10.2 in 1806, 10.1 in 1857 and 1988, and 10.0 in 1967.

The lowest daily mean (1772-2020) was -6.4 in 1870. Other low daily means include -4.4 in 1891, -4.0 in 1935, -3.8 in 1891, -3.6 in 1890, -3.4 in 1860 and 1874, -3.0 in 1878, -2.8 in 1772, 1897, 1904 and 1981, -2.6 in 1788 and 1840, -2.3 in 1963 and 2010, and -2.2 in 1799 and 1962. 

The highest maximum (1878-2020) was 14.7 in 1977. Other mild days include 12.6 in 1991, 12.3 in 1997, 12.6 in 1980, 12.5 in 1974, 12.0 in 1984, 11.8 in 1988, 11.7 in 2014, 11.6 in 1967, 2002, 2004.

The highest minimum (1878-2020) was 11.1 in 1991 which replaced 8.1 from 1974. Other mild minimum readings were 10.1 in 2014, 8.6 in 1980, 8.5 in 2011, 8.4 in 1988, 8.3 in 1967 and 2004, 7.9 in 1937 and 1977, and 7.6 in 1966, 1990 and 2002.

The lowest maximum (1878-2020) was -2.7 in 1891. Other cold values were -1.2 (1890), -0.7 (1962), -0.6 (1904), 0.1 (1961), 0.3 (1981), 0.5 (1935), 0.7 (1897),  0.8 (1878), 1.0 (2010), 1.1 (1963) and 1.5 (1950). _ (a value of -2.6 for 1884 is uncertain as it is lower than the daily minimum, could be a data error for +2.6). 

The lowest minimum (1878-2020) was -8.4 in 1935. Other cold minima include -6.8 in 1878, -6.3 in 1897, -6.0 in 1891, -5.9 in 1890 and 1981, -5.7 in 1963, -5.5 in 2010, -5.2 in 1982, -4.9 in 1904, -4.8 in 1901, -4.2 in 1994 and 2009, and -4.0 in 1917.

The wettest 23rd of December (1931-2020) in the EWP data was 28.95 mm (2013), followed by 14.01 mm (2020), 12.44 mm (1999), 12.08 mm (1985), 10.51 mm (1945) and 10.34 mm (1956). 

The wettest week ending 23rd December (17th - 23rd Dec) was 72.72 mm in 2012, followed by 66.57 mm in 2013, 60.43 mm in 1995, 54.10 mm in 1989, and 50.19 mm (1993). 

The least amount falling in a week ending 23rd December was 0.32 mm in 1961, followed by 0.50 mm in 1972, 0.68 mm in 1933, 1.08 mm in 1939, 1.50 mm in 1963, 1.67 mm in 1948, and 1.93 mm in 1941. 

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

(Today's map link is for 1991 setting mild records.) 

https://www.wetterzentrale.de/reanalysis.php?jaar=1991&maand=12&dag=23&uur=1200&var=1&map=1&model=noaa

Edited December 24, 2021 by Roger J Smith

[The PIT]

Sunny Sheffield at 5C -0.3C below average. Rainfall 64.9mm 74.2% of the monthly average

[Summer Sun]

5.9c to the 22nd

1.0c above the 61 to 90 average
1.1c above the 81 to 10 average

___________________________

Current high this month 7.3c on the 1st
Current low this month 4.9c on the 7th

[johncam]

5 minutes ago, Summer Sun said:

5.9c to the 22nd

1.0c above the 61 to 90 average
1.1c above the 81 to 10 average

___________________________

Current high this month 7.3c on the 1st
Current low this month 4.9c on the 7th

Struggling now to get to near normal.

[Roger J Smith]

Almanac for 24th December

 

The highest daily mean (1772-2020) was 10.7 in 1843; the warmest since has been 10.6 in 2002. Other mild averages were 10.2 in 1803, 10.1 in 1977, 10.0 in 1781 and 1852, and 9.9 in 1988.

The lowest daily mean (1772-2020) was -6.9 in 1870. Other low daily means include -6.7 in 1830, -5.3 in 1796, -5.0 in 1878, -4.9 in 1891, -4.7 in 1779, -4.1 in 1804, -3.8 in 1891,-3.1 in 1962, -2.8 in 2010, -2.5 in 1961, -2.4 in 1798.  . 

The highest maximum (1878-2020) was 13.0 in 1997 which replaced 12.4 from 1983, and before that the record was 11.9 in 1937. Other mild days include 12.6 in 2002, 12.2 in 1999, 12.1 in 1988, 11.8 in 1910, 1920 and 1989, 11.7 in 1977, 11.6 in 2016 and 11.4 in 1947 and 1980. 

The highest minimum (1878-2020) was 8.7 in 2002 which replaced 8.5 from 1977. Other mild minimum readings were 8.5 in 1977, 7.6 in 1988 and 7.4 in 1980.

The lowest maximum (1878-2020) was -1.8 in 1891. Other cold values were -0.5 (1962), -0.3 (2010), -0.1 (1878), 0.0 (1961), 0.9 (1904), then 1.1 (1890 and 1892), 1.3 (1992) and 1.6 (1950). (Maxima in 1830 and 1870 could have been as low as -3 or -4).

The lowest minimum (1878-2020) was -9.8 in 1878 (1830 and 1870 before this data began may have been comparable or slightly lower as the daily means were -6.7 and -6.9). Other cold minima include -7.9 in 1891, -7.6 in 1963, -7.2 in 1935, -5.6 in 1962, -5.3 in 1981 and 2010, -5.0 in 1961, -4.5 in 1881, -4.2 in 1994 and -4.0 in 1992 with -3.8 in 2009.

The wettest 24th of December (1931-2020) in the EWP data was 16.55 mm (1999), followed by 14.14 mm (1989), 11.88 mm (1968), 11.07 mm (1951) and 10.27 mm (2007). 

The wettest week ending 24th December (18th - 24th Dec) was 80.38 mm in 2012, followed by 69.83 mm in 2013, 63.91 mm in 1989, 58.60 mm in 1995, 50.63 mm (1999), and 49.91 mm (1993). 

The least amount falling in a week ending 24th December was 0.32 mm in 1961, followed by 1.06 mm in 1933, 1.12 mm in 1939, 1.26 mm in 2006, 1.53 mm in 1948, 1.80 mm in 1972, and 2.03 mm in 1941. 

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

(Today's map link is for 1870 which was setting cold records.) 

https://www.wetterzentrale.de/reanalysis.php?jaar=1870&maand=12&dag=24&uur=0600&var=1&map=1&model=noaa

Edited December 25, 2021 by Roger J Smith

[ItNeverSnowsInWindsor]

Looks like finishing well above average with Uncle Bartlett setting shop post Xmas.

[Frigid]

At least from this we may achieve the 5.9C CET

[The PIT]

Sunny Sheffield at 5C -0.2C below average, Rainfall 65.9mm 75.3% of average

[Summer Sun]

5.9c to the 23rd

1.0c above the 61 to 90 average
1.1c above the 81 to 10 average

___________________________

Current high this month 7.3c on the 1st
Current low this month 4.9c on the 7th

[Don]

3 hours ago, Frigid said:

At least from this we may achieve the 5.9C CET

Doubt it, possibly mid-6's after adjustments?!

[Roger J Smith]

Almanac for 25th December

 

The highest daily mean (1772-2020) was 10.4 in 1824 tied in 1983. 10.4 is the lowest value for December for this statistic, although over a dozen days in January and early February have lower values (the lowest of all is 9.8 for 28 Jan).  This is also the only tied record high in December. Other mild averages were 9.7 in 2017, 9.5 in 2016, 9.4 in 1806 and 1931, and 9.3 in 1988.

The lowest daily mean (1772-2020) was -10.8 in 1796 which is the lowest value for December and also second lowest of all the data (the 20th of  Jan 1838 was -11.9). Other low daily means include -6.6 in 1830, -5.9 in 2010, -5.8 in 1878, -5.1 in 1779, -4.4 in 1840 and 1870, -4.0 in 1772, -3.7 in 1798, -3.6 in 1962, -3.2 in 1835, and -2.6 in 1961. 

The highest maximum (1878-2020) was 13.1 in 2015 and 2016, which replaced 12.9 from 1900. Other mild days include 12.5 in 1974, 12.0 in 1955, 11.8 in 1988 and 2011, 11.5 in 1949 and 1983, 11.4 in 1931, and 11.3 in 1954. 

The highest minimum (1878-2020) was 9.3 in 1983 which replaced 8.2 from 1941. Other mild minimum readings were 8.5 in 2017, 7.7 in 1977, and 7.4 in 1931 and 2003.

The lowest maximum (1878-2020) was -2.6 in 2010 (1796 may have been quite a bit lower although from the mean value for the 26th perhaps quite a large range from -16 to -6 for the 25th) ... Other cold values were -0.4 (1962), -0.3 (1878), -0.1 (1944), 0.2 (1892), 0.3 (1961), 0.9 (1895), 1.0 (1890, 1904 and 1938), and 1.3 (1956 and 1964).

The lowest minimum (1878-2020) was -11.2 in 1878 (1796 was probably around -15 however). The coldest since 1878 was the -9.2 reading in 2010. Other cold minima include -7.9 in 1891, -6.7 in 1962, -5.9 in 1923, -5.6 in 1963, -5.5 in 1961, -5.0 in 1892, -4.5 in 1925, and -4.0 in 1981.

The wettest 25th of December (1931-2020) in the EWP data was 14.09 mm (1934), followed by 13.79 mm (2015), 12.90 mm (1959), 12.14 mm (1985), 12.05 mm (1990), 12.03 mm (1960), 11.73 mm (2017), 11.14 mm (1998), and 10.82 mm (1974). 

The wettest week ending 25th December (19th - 25th Dec) was 82.13 mm in 2012, followed by 59.49 mm in 2013, 56.59 mm in 1995, 52.48 mm in 1989, 51.24 mm (1999), and 50.00 mm (1985).

The least amount falling in a week ending 25th December was 0.73 mm in 1961, followed by 0.88 mm in 2006, 1.08 mm in 1992, 1.45 mm in 1948, 1.52 mm in 1939, 1.61 mm in 1940, and 2.09 mm in 1941. 

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

(Today's map link is for 1962 as the persistent cold of that famous winter began to dig in.) 

https://www.wetterzentrale.de/reanalysis.php?jaar=1962&maand=12&dag=25&uur=0600&var=1&map=1&model=noaa

Merry Christmas !

 

Edited December 25, 2021 by Roger J Smith

[The PIT]

Sunny Sheffield still at 5C -0.1C below average, Rainfall 73.3mm 83.8% of the monthly total.

Finally ending looks to be around 5.2C to 5.4C here. So close to average and no where near the dreaded 6C mark.

[Summer Sun]

5.9c to the 24th

1.1c above the 61 to 90 average
1.1c above the 81 to 10 average

___________________________

Current high this month 7.3c on the 1st
Current low this month 4.9c on the 7th

[Roger J Smith]

EWP projection is around 90 mm with 58 mm to 23rd, grid average for 24th appears to be close to 10 mm, then another 20-25 mm depicted by end of 31st on GFS accumulated precip charts. 90 mm is a little below normal but nowhere near the dry finish that the GFS was showing about five days ago (along with its other amended ideas about temperatures). The fact of the matter is that half the field in this contest had a better forecast on or before the first of the month than the GFS had on the 20th. 

[Roger J Smith]

Almanac for 26th December

 

The highest daily mean (1772-2020) was 11.0 in 2011. This replaced 10.9 from 1988, which in turn had replaced 9.9 set in 1931. Other mild averages were 10.2 in 2015, 9.8 in 1920, 9.4 in 1842 and 1852 and 9.3 in 2003.

The lowest daily mean (1772-2020) was -5.4 in 1798. Other low daily means include -3.9 in 1892, -3.6 in 2010, -3.5 in 1962, -3.2 in 1835, -3.1 in 1796 and 1808, -3.0 in 1870, and -2.7 in 1860. 

The highest maximum (1878-2020) was 13.8 in 2015, which replaced 13.0 from 1988, before that the record was 11.8 from 1898. Other mild days include 12.4 in 2011, 12.1 in 1998, 12.0 in 1990, 11.7 in 1931, 1949, and 1955, 11.5 in 1983, 11.4 in 1896, 1920, 1947 and 1994, 11.3 in 1953, 1958 and 1987, and 11.2 in 1974. 

The highest minimum (1878-2020) was 9.7 in 2011 which replaced 8.8 from 1988 Before that the record was 8.2 from 1920. Other mild minimum readings were 8.5 in 2003, and 8.1 in 1931. 

The lowest maximum (1878-2020) was -0.8 in 1906 (1798 was probably a bit lower at least, around -2 to -3 possibly) ... Other cold values were -0.2 (1892), 0.5 (1948), 1.0 (1962), 1.1 (1895), 1.2 (1968) and 1.5 (1944). 2010 warmed to 2.5 by end of the day.

The lowest minimum (1878-2020) was -9.7 in 2010. Other cold minima include -7.6 in 1892, -6.5 in 1964, -5.2 in 1944, -5.1 in 1981, -5.0 in 1961, -4.7 in 1891, -4.5 in 1995 and -4.0 in 1906 and 1996.

The wettest 26th of December (1931-2020) in the EWP data was 17.95 mm (2020), followed by 16.44 mm (1979), 16.17 mm (1994), 15.91 mm (2017), 13.99 mm (2014), 11.06 mm (2002), and 10.97 mm (1947). 

The wettest week ending 26th December (20th - 26th Dec) was 68.37 mm in 2012, followed by 63.16 mm in 2013, 56.46 mm (2002), 54.89 mm (1999), 49.86 mm (2020), and 49.78 mm (1985).

The least amount falling in a week ending 26th December was 0.47 mm in 1992, then 0.77 mm in 2006, 1.05 mm in 1961, 1.15 mm in 1940, 1.45 mm in 1948, 1.50 mm in 2008 and 2.00 mm in 1939. 

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

(Today's map link is for 1892, quite cold for several days.) 

https://www.wetterzentrale.de/reanalysis.php?jaar=1892&maand=12&dag=26&uur=0600&var=1&map=1&model=noaa

Edited December 27, 2021 by Roger J Smith

[Frigid]

It looks like December may have a greater CET than April which stood at 6.4C. Last time this happened was in 2015. 

[The PIT]

Sunny Sheffield down to 4.9C -0.1C below average. Rainfall 84.9mm 97% of the monthly average.

Probably low point of the month. Estimated end pint for us 5.4C to 5.7C

[Summer Sun]

5.9c to the 25th

1.1c above the 61 to 90 average
1.1c above the 81 to 10 average

___________________________

Current high this month 7.3c on the 1st
Current low this month 4.9c on the 7th

[Roger J Smith]

This is a list of Dec-Jan combos where both months exceeded 6.0 ...

the order is reverse chronological (going back through time). 

2006-07 __ 6.5, 7.0 (6.75 - 6)

1988-89 __7.5, 6.1 (6.80  - 5)

1974-75 __8.1, 6.8 (7.45 - 2)

1833-34 __6.9, 7.1 (7.00 - 3)

1795-96 __6.6, 7.3 (6.95 - 4)

1736-37 __6.4, 6.2 (6.30 -11)*

1685-86 __6.5, 6.5 (6.50 - 7)

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

rest of the top 20 Dec - Jan all those with averages 5.9 or higher _

* ties are separated by higher base value _ this added portion is in rank order

2015-16 __9.7, 5.4 (7.55 - 1)

1868-69 __7.2, 5.6 (6.40 - 8)*

1915-16 __5.3, 7.5 (6.40 - 9)*

1852-53 __7.7, 5.1 (6.40 -10)*

1934-35 __8.1, 4.5 (6.30 -12)*

1710-11 __7.5, 5.0 (6.25 -13)

2019-20 __5.8, 6.4 (6.10 -14)*

1898-99 __7.3, 4.9 (6.10 -15)*

1924-25 __6.8, 5.3 (6.05 -16)

2013-14 __6.3, 5.7 (6.00 -17)*

1827-28 __6.9, 5.1 (6.00 -18)*

1733-34 __7.6, 4.3 (5.95 -19)

1735-36 __5.4, 6.4 (5.90 -20)

1865-66 (5.8, 5.8), 1931-32 (5.3, 6.3), 1942-43 (6.7, 4.9) were just outside the top 20. 

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

The average Feb CET of the 23 winters listed above was 4.9, the range was 0.6 (Feb 1853) to 7.5 (Feb 1869). Besides 1853, only two other Feb CET managed to push below 3.0, those being 2.0 in 1711 and 2.9 in 1932. 

These mild Dec-Jan combinations anchored most of the top 20 CET winters, the furthest down the list that any of them went was t-116th warmest for 1852-53. A few top 20 winters such as 1997-98 and 2018-19 lurked just below the cutoff and got in with a milder February (above 6.5). 

 

[Roger J Smith]

Almanac for 27th December

 

The highest daily mean (1772-2020) was 10.9 in 2015. This replaced 10.6 from 1987, which in turn had replaced 10.3 from 1974, which had replaced 10.2 from 1949. That had replaced 9.9 set in 1876 and tied in 1882. Beside all these ascending record highs the next highest values were 9.8 in 1954, 9.6 in 1898, 9.4 in 1909 and 9.3 in 1920.

The lowest daily mean (1772-2020) was -8.4 in 1798. Other low daily means include -4.9 in 1892, -3.7 in 1860, -3.4 in 1899, -2.8 in 1995 and -2.7 in 1829 and 1870. We bid farewell to 2010 which had -1.7. 1962 at -1.6 also drops from the list but returns tomorrow.

The highest maximum (1878-2020) was 13.9 in 1974, which replaced 12.7 from 1955. Other mild days include 13.3 in 2015, 12.9 in 1994, 12.6 in 1987, 12.4 in 1983, 12.2 in 1958, 12.1 in 1912, 12.0 in 1882 and 1921, 11.7 in 1947 and 1949, 11.6 in 1915, 1954 and 2007, 11.5 in 1920, 11.4 in 1988, and 11.2 in 1898 and 1924.

The highest minimum (1878-2020) was 8.7 in 1949 which replaced 8.0 from 1898. Other mild minimum readings were 8.6 in 1987, 8.5 in 2015, 8.3 in 2011, 8.0 in 1954, 7.9 in 1909 and 2002, 7.8 in 1882, 7.6 in 1902 and 7.3 in 1931. 

The lowest maximum (1878-2020) was -0.9 in 1899 (1798 was probably closer to -4) ... ... Other cold values were -0.6 (1892), -0.5 (1995), -0.1 (1887),  0.2 (1962), 0.6 (1908 and 1965), 0.9 (1985), 1.2 (1970), 1.3 (1961), 1.4 (1895, 1906 and 1948) and 1.5 (1950 and 1952). 

The lowest minimum (1878-2020) was -9.1 in1892. (1798 likely around -12). Other cold minima include -6.7 in 2010, -5.8 in 1899, -5.1 in 1995, -5.0 in 1916, -4.9 in 1944, -4.6 in 1906, -4.5 in 1887, -4.4 in 1965 and -4.1 in 1961. (-3.3 in 1962)

The wettest 27th of December (1931-2020) in the EWP data was 28.17 mm (1979), followed by 18.42 mm (1978), 13.31 mm (1994), 10.53 mm (1935) and 10.27 mm (1956). 

The wettest week ending 27th December (21st - 27th Dec) was 61.98 mm in 2012, followed by 58.63 mm in 2013, 54.80 mm (2002), 52.98 mm (1978), and 51.59 mm (1999).

The least amount falling in a week ending 27th December was 0.39 mm in 1992, then 0.83 mm in 2008, 1.02 mm in 1961, followed by 1.32 mm in 1940, and 1.85 mm in 1948. 

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

(Today's map link is for 1979, very wet two-day total EWP of 44.61 mm for 26-27 Dec. Some lesser amounts in coming days will lift this year into the 50 mm weekly category, it was at 48.95 mm in today's data. From a different low over eastern North America, similar rainfall records were being set on Christmas Day 1979 and into the 26th. That would be the low on the western margin of the maps.) 

https://www.wetterzentrale.de/reanalysis.php?jaar=1979&maand=12&dag=27&uur=0600&var=1&map=1&model=noaa

Edited December 27, 2021 by Roger J Smith

[Optimus Prime]

Well one thing is for sure. A hideously warm end to another dreadful December. It hasn't felt like a winter month since the early part of 2012 really. The change from it being quite a promising month for cold prospects just a few years ago to being a drop in replacement for March really contrasts. I cannot think of a month that comes close to having changed as markedly as this one nor as rapidly.

Edited December 27, 2021 by Optimus Prime

[The PIT]

Sunny Sheffield still at 4.9C -0.1C below normal. Rainfall 88.3mm 100.9% of the monthly average.

Landing zone for us looks like being between 5.4C and 5.7C.

[Summer Sun]

5.9c to the 26th

1.1c above the 61 to 90 average
1.2c above the 81 to 10 average

___________________________

Current high this month 7.3c on the 1st
Current low this month 4.9c on the 7th

[North-Easterly Blast]

11 hours ago, Optimus Prime said:

Well one thing is for sure. A hideously warm end to another dreadful December. It hasn't felt like a winter month since the early part of 2012 really. The change from it being quite a promising month for cold prospects just a few years ago to being a drop in replacement for March really contrasts. I cannot think of a month that comes close to having changed as markedly as this one nor as rapidly.

Yes very true.  In actual fact Decembers in the 1990s and 2000s largely escaped the warming trend seen in many other months of the year and especially so January and February.  After the exceptionally cold December of 2010 had passed, that trend appears to have reversed and there has been a run of mostly mild Decembers since then, and December has not been below the 1981-2010 average at all now since 2010.  Since 2010 the only cold periods that I can think of in December have been; the first half of Dec 2012 was cold, and the first half of Dec 2017 had a cold spell in it, and late Dec 2014 saw a cold few days, as did late Dec 2020.  Other than that the rest of the time, Decembers since 2010 have seen only isolated cold one to three days.