March 2023 C.E.T. and EWP forecast contests

[Summer Sun]

6.6c to the 26th

0.9c above the 61 to 90 average
0.2c above the 81 to 10 average

[The PIT]

Sunny Sheffield at 6.4C still +0.2C above average. Rainfall 103.6mm 171% of the monthly average.

No change for today as temperatures reached normal values. Could well stay the same right up the 28th.

 

[LetItSnow!]

5 hours ago, Roger J Smith said:

EWP has reached 105 mm (at least) and looks set to add 20-25 mm more, to finish in the top four possibly. Even third seems possible, on current guidance first and second are out of reach. The current top five are:

 1 __ 1947 _ 177.5 mm

 2 __ 1981 _ 160.4 mm

 3 __ 1818 _ 134.7 mm

 4 __ 1979 _ 127.0 mm

 5 __ 1919 _ 120.0 mm

______________________________

The rest of the top ten which seem very likely to be passed by 2023 are: 

 6 __ 119.7 _ 1914

 7 __ 119.5 _ 1836

 8 __ 118.4 _ 1912

 9 __ 116.2 _ 1951

10__ 115.1 _ 2018

The current value of 105 mm would rank 22nd so we may be passing 22nd to 11th ranked months of March on a regular basis starting Tuesday. 

 

 

Goes to show you how impressive March 1981 must have been as ‘47 had a lot of snow melt but February 1981 had only been snowy locally and March 1981 was very mild. It’s a fair wack wetter than the third entry too. 

[cheeky_monkey]

currently Edmonton stands at mean of -9.5c for March..which currently is colder than January by 0.5c and the same value as February 

[emmett garland]

10 minutes ago, cheeky_monkey said:

currently Edmonton stands at mean of -9.5c for March..which currently is colder than January by 0.5c and the same value as February 

Its an Icy world you really live in during winter.. We can only imagine,,Come on Ireland in the footy against the mighty French,,

[damianslaw]

7 hours ago, Roger J Smith said:

EWP has reached 105 mm (at least) and looks set to add 20-25 mm more, to finish in the top four possibly. Even third seems possible, on current guidance first and second are out of reach. The current top five are:

 1 __ 1947 _ 177.5 mm

 2 __ 1981 _ 160.4 mm

 3 __ 1818 _ 134.7 mm

 4 __ 1979 _ 127.0 mm

 5 __ 1919 _ 120.0 mm

______________________________

The rest of the top ten which seem very likely to be passed by 2023 are: 

 6 __ 119.7 _ 1914

 7 __ 119.5 _ 1836

 8 __ 118.4 _ 1912

 9 __ 116.2 _ 1951

10__ 115.1 _ 2018

The current value of 105 mm would rank 22nd so we may be passing 22nd to 11th ranked months of March on a regular basis starting Tuesday. 

 

 

Thanks, I knew it has been wet, but not quite that wet! Here we have had many days with large totals, and I guess it has been the large absence of any dry weather rather than major single rainfall events that has resulted in such totals. A very wet 48 hrs ahead will help push 2023 up the table. We've not been used to very wet months recently.

1 hour ago, LetItSnow! said:

Goes to show you how impressive March 1981 must have been as ‘47 had a lot of snow melt but February 1981 had only been snowy locally and March 1981 was very mild. It’s a fair wack wetter than the third entry too. 

March 1979 brought a lot of snow mid month as well, not on a scale of 1947 but interesting to see it in the Top 5.

[damianslaw]

6 hours ago, Summer Sun said:

6.6c to the 26th

0.9c above the 61 to 90 average
0.2c above the 81 to 10 average

A probable drop tomorrow to 6.5 degrees given the widespread low minima and temps struggling to get much above 10 degrees for many. Maxima tomorrow will be supressed for a time but then rise later in the day, so a likely increase on Wednesday. I will guess a finish of 6.7-6.9 degrees. 

[Weather-history]

1 hour ago, LetItSnow! said:

Goes to show you how impressive March 1981 must have been as ‘47 had a lot of snow melt but February 1981 had only been snowy locally and March 1981 was very mild. It’s a fair wack wetter than the third entry too. 

It was absolutely horrific March 1947, all that snow that had accumulated and then you have a thaw  with accompanying heavy rain as well. Nottingham had its wettest March day for 58 years with 1.3 inches of rain when the thaw finally came. Streets everywhere were turned into slushfests.

The wettest March day on record for the EWP was the day the thaw broke through for England and Wales on 12th March 1947

[Don]

43 minutes ago, damianslaw said:

A probable drop tomorrow to 6.5 degrees given the widespread low minima and temps struggling to get much above 10 degrees for many. Maxima tomorrow will be supressed for a time but then rise later in the day, so a likely increase on Wednesday. I will guess a finish of 6.7-6.9 degrees. 

Who would have thought that 3 weeks ago?!

[damianslaw]

38 minutes ago, Don said:

Who would have thought that 3 weeks ago?!

Its done a bit of a March 2006 except instead of just one very mild week at the end, we've had 2 very mild weeks. March is a warming month and one which can switch from winter cold to early spring warmth quite quickly.

[Don]

34 minutes ago, damianslaw said:

Its done a bit of a March 2006 except instead of just one very mild week at the end, we've had 2 very mild weeks. March is a warming month and one which can switch from winter cold to early spring warmth quite quickly.

Indeed, but still disappointing as a colder than average month did look realistic.

[Weather-history]

On 12/03/2023 at 17:23, Daniel* said:

-1.1C exceptionally cold. Anomaly on right 6C below average. Huge!

 

Look at the change now, -ve anonalies are getting smaller and being pushed further north 

Edited March 28, 2023 by Weather-history

[Summer Sun]

6.6c to the 27th

0.9c above the 61 to 90 average
0.2c above the 81 to 10 average

[LetItSnow!]

I remember a topic of conversation a while ago speaking on the largest increases in precipitation month to month (very dry months followed by very wet months), will February and March 2023 likely be joining this list? I think there have been larger differences but I can’t remember. Might have been back in 1865. 

[damianslaw]

51 minutes ago, LetItSnow! said:

I remember a topic of conversation a while ago speaking on the largest increases in precipitation month to month (very dry months followed by very wet months), will February and March 2023 likely be joining this list? I think there have been larger differences but I can’t remember. Might have been back in 1865. 

Yes reminds me of the switch between March and April 2012 in lots of ways. April and May 1997 also to an extent. Feb 1997 and March 1997.

 

12 hours ago, Weather-history said:

Look at the change now, -ve anonalies are getting smaller and being pushed further north 

Are these against the 81-10 mean I assume and not the 61-90 mean. The northern half of the UK is experiencing a very close to or notably below average March, look at those anomalies in the north of Scotland, 3 degrees below, long time since had such a deviation, suspect April 2021 the last time.

 

[SummerShower]

1 hour ago, LetItSnow! said:

I remember a topic of conversation a while ago speaking on the largest increases in precipitation month to month (very dry months followed by very wet months), will February and March 2023 likely be joining this list? I think there have been larger differences but I can’t remember. Might have been back in 1865. 

April and May 2007

To some degree Jan and Feb last year also

 

[Weather-history]

39 minutes ago, damianslaw said:

 

Are these against the 81-10 mean I assume and not the 61-90 mean. The northern half of the UK is experiencing a very close to or notably below average March, look at those anomalies in the north of Scotland, 3 degrees below, long time since had such a deviation, suspect April 2021 the last time.

 

There against 1991-2020 averages. Are those anomalies that impressive against this average? In any case the milder end to the month are just going to squeeze those -ve anomalies further.

Edited March 28, 2023 by Weather-history

[Roger J Smith]

4 hours ago, LetItSnow! said:

I remember a topic of conversation a while ago speaking on the largest increases in precipitation month to month (very dry months followed by very wet months), will February and March 2023 likely be joining this list? I think there have been larger differences but I can’t remember. Might have been back in 1865. 

Here are the current top 25 (all cases over 120.0 change) in total, for both directions: 

LARGEST MONTH to MONTH INCREASES in EWP 1766-2022 ___ LARGEST MONTH to MONTH DECREASES in EWP 1766-2022

01 __ Sep 1795 12,9 _ Oct 1795 173.2 ___ +160.3 ________________ 01 __ Oct 1903 218.1 __ Nov 1903 70.1 ___-148.0

02 __ Sep 1865 9.5 __ Oct 1865 168.4 ___ +158.9 ________________ 02 __Aug 1912 192.9 __ Sep 1912 50.0 ___ -142.9

03 __ Oct 1951 33.2 __Nov 1951 180.4 ___+147.2 ________________03 __ Dec 1934 183.5 __ Jan 1935 42.3 ___ -141.2

04 __ Jan 1833 27.9 __ Feb 1833 158.6 ___ +130.7 _______________ 04 __ Nov 1963 165.9 __ Dec 1963 30.1 ___-135.8

05 __ Sep 1907 22.6 __ Oct 1907 152.6 ___+130.0 ________________05 __ Dec 1821 166.0 __ Jan 1822 32.2 ___ -133.8

06 __ Aug 1918 62.9 __ Sep 1918 189.5 ___+126.6 _______________ 06 __ Nov 1926 157.9 __ Dec 1926 24.5 ___-133.4 

07 __ Sep 1843 24.3 __ Oct 1843 150.4 ___+126.1 ________________07 __ Dec 1915 184.9 __ Jan 1916 56.6 ___ -128.3

08 __ Aug 1976 25.2 __ Sep 1976 150.8 ___+125.6 _______________ 08 __ Jan 1948 176.8 __ Feb 1948 49.9 ___ -126.9

09 __ Nov 1868 61.4 __ Dec 1868 185.6 ___+124.2 _______________09 __ Nov 1970 178.6 __ Dec 1970 53.9 ___ -124.7

10 __ Oct 1969 17.5 __ Nov 1969 138.3 ___+120.8 _______________ 10 __ Nov 1940 162.1 __ Dec 1940 60.5 ___ -123.4

t11__ Nov 1934 63.4 __Dec 1934 183.5 ___+120.1 _______________ 11 __ Feb 1990 143.2 __ Mar 1990 22.5 ___ -120.7 

t11__ Sep 1855 37.1 __ Oct 1855 157.2 ____+120.1 ______________ 12 __ Sep 1918 189.5 __ Oct 1918 69.1 ___ -120.4

............................................................................................................... 13 __ Sep 1774 161.0 __ Oct 1774 40.9 ___ -120.1

(no other calendar months than those included above ___ []_______ unknown would be Dec 1765 to very dry Jan 1766 (4.4 mm)

exceeded 120.0, The current Feb-Mar max increase is ____[]_______these lists give all 25 cases of 120.0 or more. There are two

119.2 mm from 58.3 to 177.5 in 1947, and for Mar-Apr ___[]_______ pairs (Aug-Oct 1918, Nov 1934-Jan 1935). Aug 1865 to Sep

119.0 mm from 30.9 to 149.9 in 2012. ____________________ []_______1865 dropped by 116.5, not quite making list above.

_____________________________________________________________[]_______ Another near miss Oct-Nov 1970 incr by 116.5 

MORE RECENT ...

Mar 2023 will need to reach 136.6 mm to equal t11 above, ________ Largest decrease of 21st century so far is 

as Feb 2023 was 16.5 mm (this may change slightly as EWP ________ 111.6 mm from 169.5 to 57.9 mm Feb-Mar 2020.

values are adjusted several times for 2-3 months after first ________ second is 106.7 mm from Aug to Sep 2004

appearing in tables). Before this case or Mar-Apr 2012, the _________ (156.5 mm to 49.8 mm). Next is 104.7 mm 

largest increase in the 21st century was 114.2 mm from _____________ (Jan 2008 144.9 to Feb 2008 40.2). 

Oct 2009 (77.9) to Nov 2009 (192.1) , then 109.2 mm from 

Apr 2021 (13.5) to May 2021 (122.7) and also in spring 2007

Apr (10.4) to May (118.4) increased 108.0 mm, matched by

Sep (56.1) to Oct (164.1) in 2020. 

 

 

 

Edited March 28, 2023 by Roger J Smith

[Don]

1 hour ago, Weather-history said:

There against 1991-2020 averages. Are those anomalies that impressive against this average? In any case the milder end to the month are just going to squeeze those -ve anomalies further.

Yes, mild has won out this month! 

[Roger J Smith]

Wouldn't say it's all that mild given that (for 6.9 or 7.0 finish) there are 21 of the past 42 years warmer and 21 colder (at 6.8 it would be tied with 2011 and 2020 as 20th coldest of past 43). Also the 1991-2020 and 1993-2022 averages were 6.75 rounding down to 6.7. So a finish between 6.8 and 7.0 will be fairly ordinary in the larger picture.  

 

 

[Don]

6 minutes ago, Roger J Smith said:

Wouldn't say it's all that mild given that (for 6.9 or 7.0 finish) there are 21 of the past 42 years warmer and 21 colder (at 6.8 it would be tied with 2011 and 2020 as 20th coldest of past 43). Also the 1991-2020 and 1993-2022 averages were 6.75 rounding down to 6.7. So a finish between 6.8 and 7.0 will be fairly ordinary in the larger picture.  

 

 

True but it will be more than a degree above the old and cold 61-90 average.

[Roger J Smith]

Yes, and looking back at the opening post, I have 5.1 as the average of 1701-1900 for two entire centuries, and even colder in the Maunder. The running 30-year mean almost made it to 6.0 by 1938-67 then fell back and only started to exceed 6.0 quite recently. March basically used to be what February is nowadays. 

[Greyhound81]

I have noticed that the CET does not get adjusted down (by about 0.2 degrees) at the end of the month any more.  Does it now get adjusted down every day or is not adjusted at all?

[Roger J Smith]

Just now, Greyhound81 said:

I have noticed that the CET does not get adjusted down (by about 0.2 degrees) at the end of the month any more.  Does it now get adjusted down every day or is not adjusted at all?

We have noticed a few changes made in month such as minor changes to some of the colder values in mid-Dec 2022, but generally speaking the adjustments are few, and as you say they don't go back through all values at end of month, so I think in every case now since this change in May 2022, what we see on 1st of month following is what we get permanently in the tables. I have looked back a couple of times and failed to find any after-the-fact changes made. 

EWP changes several times before settling at final values in tables. 

[Daniel*]

On 27/03/2023 at 20:53, damianslaw said:

A probable drop tomorrow to 6.5 degrees given the widespread low minima and temps struggling to get much above 10 degrees for many. Maxima tomorrow will be supressed for a time but then rise later in the day, so a likely increase on Wednesday. I will guess a finish of 6.7-6.9 degrees. 

No drop whatsoever from this “colder spell” very surprising, it’s the cloud cover this month which has done it prevented nights from getting cold. I’m not a fan of this revision to CET, a number of times I’ve scratched my head. Why change something which was fine?