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

[damianslaw]

A significantly cold first half to March, are we to see one of those switcharound months, cold first half cancelled out by mild second half.. not so sure, whilst the next week or so looks mild, we could see a colder last week or so. Odds of a below average month seem quite high still. Let's see where we are in a week's time.

Edited March 16, 2023 by damianslaw

[Derecho]

23 minutes ago, damianslaw said:

A significantly cold first half to March, are we to see one of those switcharound months, cold first half cancelled out by mild second half.. not so sure, whilst the next week or so looks mild, we could see a colder last week or so. Odds of a below average month seem quite high still. Let's see where we are in a week's time.

I don't think it's that impressive to be brutally honest. We are only a degree below the 1961-1990 average up to the 15th March. It's only the 89th coldest first half since 1772. 1947 and 1845 both had sub zero CETs up to this point.

Based on the 12z GFS the CET would rise to 6.6C by the end of the month. Still think they could be a cold shot at the end of the month but that figure is 1C above the 1961-1990 average.

[Daniel*]

6 minutes ago, Quicksilver1989 said:

I don't think it's that impressive to be brutally honest. We are only a degree below the 1961-1990 average up to the 15th March. It's only the 89th coldest first half since 1772. 1947 and 1845 both had sub zero CETs up to this point.

Based on the 12z GFS the CET would rise to 6.6C by the end of the month. Still think they could be a cold shot at the end of the month but that figure is 1C above the 1961-1990 average.

GFS keeps going “warm”. EPS going for a cooler end to March.

[Derecho]

10 minutes ago, Daniel* said:

GFS keeps going “warm”. EPS going for a cooler end to March.

Hmmm I'm not convinced. There is a signal in the EC ens at day 10 for pressure to rise just to the west of Spain, so could well carry warmth with it. There is cold to the north but at best I can just see a cyclonic pattern returning and a north-south divide.

A long way off though. Bear in mind the March average for 1991-2020 is around 1.5C warmer then that observed from 1961-1990 (actually its a little less then that but still, a big difference).

Edited March 16, 2023 by Quicksilver1989

[damianslaw]

13 minutes ago, Quicksilver1989 said:

I don't think it's that impressive to be brutally honest. We are only a degree below the 1961-1990 average up to the 15th March. It's only the 89th coldest first half since 1772. 1947 and 1845 both had sub zero CETs up to this point.

Based on the 12z GFS the CET would rise to 6.6C by the end of the month. Still think they could be a cold shot at the end of the month but that figure is 1C above the 1961-1990 average.

Perhaps so, but given how mild most months have been recently, its quite notable. I expect the mean for Scotland is significantly below, and it has been cold here in Cumbria.

[Derecho]

5 minutes ago, damianslaw said:

Perhaps so, but given how mild most months have been recently, its quite notable. I expect the mean for Scotland is significantly below, and it has been cold here in Cumbria.

Yup Scotland has been a fair bit colder which is to be expected given the cyclonic pattern. At this time of the year though I'd prefer much sharper cold then the messy synoptics we've been dealing with. Ah well maybe next winter (probably not December given the possible El Nino later this year).

[Daniel*]

16 minutes ago, damianslaw said:

Perhaps so, but given how mild most months have been recently, its quite notable. I expect the mean for Scotland is significantly below, and it has been cold here in Cumbria.

Yes Altnaharra, N Scotland. To 16th

mean max 3.7C

mean min -5.2C!

Edited March 16, 2023 by Daniel*

[Don]

2 hours ago, damianslaw said:

A significantly cold first half to March, are we to see one of those switcharound months, cold first half cancelled out by mild second half.. not so sure, whilst the next week or so looks mild, we could see a colder last week or so. Odds of a below average month seem quite high still. Let's see where we are in a week's time.

Trouble is cold first halves of months are cancelled out pretty easily by milder second halves these days!

1 hour ago, Quicksilver1989 said:

Yup Scotland has been a fair bit colder which is to be expected given the cyclonic pattern. At this time of the year though I'd prefer much sharper cold then the messy synoptics we've been dealing with. Ah well maybe next winter (probably not December given the possible El Nino later this year).

If El Nino develops into a strong east based event, then winter 2023/24 could be over before it begins!

[Derecho]

28 minutes ago, Don said:

Trouble is cold first halves of months are cancelled out pretty easily by milder second halves these days!

If El Nino develops into a strong east based event, then winter 2023/24 could be over before it begins!

Not necessarily, El Nino winters tend to be back loaded (colder in the latter half of winter), whereas La Ninas tend to be more blocked in December.

Cold Decembers during an El Nino are uncommon but when they do occur they are usually part of a blocked winter throughout (e.g. 2009/10, 1968/69, 1939/40).

[Weather-history]

On 12/03/2023 at 10:37, BLAST FROM THE PAST said:

BLAST FROM THE PAST

Posted January 3

Location: Redhill, Surrey

March 23…..a month to remember.  HP control 1st ten days or so, either cold continental or milder SE/S’ly flow.  Dramatic Deep LP plunges over UK SSE bringing coldest 2nd half of month for decades.  Cyclonic N and NE’ly winds

 

BFTP
 

 

Yes the models did make one think that the cold spell was ushering quicker than anticipated.  But goalposts still in place

 

BFTP

I think it is time to face the uncomfortable fact, that your forecast of the coldest 2nd half of March for decades is going down the swanee.

We do have a recent baseline for a very cold 2nd half of March in 2013 and that was exceptional, a CET of 1.9°C  I don't know if you overlooked this when you made your prediction but the models are not showing anything on this scale. It looks more likely the second half of this March is going to be milder than the first half possibly by a margin.

Edited March 17, 2023 by Weather-history

[Relativistic]

12 hours ago, Daniel* said:

Yes Altnaharra, N Scotland. To 16th

mean max 3.7C

mean min -5.2C!

Surely that's close to the running record? Very impressive either way.

[LetItSnow!]

6 hours ago, Weather-history said:

I think it is time to face the uncomfortable fact, that your forecast of the coldest 2nd half of March for decades is going down the swanee.

We do have a recent baseline for a very cold 2nd half of March in 2013 and that was exceptional, a CET of 1.9°C  I don't know if you overlooked this when you made your prediction but the models are not showing anything on this scale. It looks more likely the second half of this March is going to be milder than the first half possibly by a margin.

Unfortunately, predictions based on hunches or personal bias are the best that any of us can do. Seems like quite a normal if not very wet March down here. I like normal. We get such little normality in our weather now compared to times before  it seems 

[LetItSnow!]

13 hours ago, Quicksilver1989 said:

Hmmm I'm not convinced. There is a signal in the EC ens at day 10 for pressure to rise just to the west of Spain, so could well carry warmth with it. There is cold to the north but at best I can just see a cyclonic pattern returning and a north-south divide.

A long way off though. Bear in mind the March average for 1991-2020 is around 1.5C warmer then that observed from 1961-1990 (actually its a little less then that but still, a big difference).

March seems like the month that warmed the quickest through the late 1980s and into the 1990s. Indeed only since 1987 have 1996, 2001, 2006, 2013 and 2018 had what you could call an appreciably cold March. Compared to other months it’s been a lot faster at warming, quite like December and February - though January has been slower in recent history. I’m sure there’s a reason why.

[kold weather]

14 hours ago, Quicksilver1989 said:

I don't think it's that impressive to be brutally honest. We are only a degree below the 1961-1990 average up to the 15th March. It's only the 89th coldest first half since 1772. 1947 and 1845 both had sub zero CETs up to this point.

Based on the 12z GFS the CET would rise to 6.6C by the end of the month. Still think they could be a cold shot at the end of the month but that figure is 1C above the 1961-1990 average.

I'd say the first 10 days were significant, especially given we were running colder than March 13 at that point.

However ultimately probably going to be close to average, but modestly above the 61-90 average.

[Derecho]

58 minutes ago, kold weather said:

I'd say the first 10 days were significant, especially given we were running colder than March 13 at that point.

However ultimately probably going to be close to average, but modestly above the 61-90 average.

That's a fair point and in northern Scotland it has been noteworthy, just a shame the cold came along so late. I don't mind cold at this time of the year if there is plenty of sunshine but March 2023 isn't exactly ticking that box....

[Derecho]

1 hour ago, LetItSnow! said:

March seems like the month that warmed the quickest through the late 1980s and into the 1990s. Indeed only since 1987 have 1996, 2001, 2006, 2013 and 2018 had what you could call an appreciably cold March. Compared to other months it’s been a lot faster at warming, quite like December and February - though January has been slower in recent history. I’m sure there’s a reason why.

From November -  January that's when solar radiation is at its minimum so the synoptics don't need to be impressive to get in decent cold. Get a period of clear nights and slack winds and you'll also start getting cold days too regardless of how high T850s are.

Though at this time of the year you'd get warm days followed by chilly days and large diurnal temperature ranges but overall above average temps (unless you got cloudy days and clear nights like in April 2021).

Edited March 17, 2023 by Quicksilver1989

[Roger J Smith]

EWP now around 60 mm and GFS to end of month says add 40 to that, 100 mm still basically good for the earlier posted scoring. ProlongedSnowLover would be a bit more comfortable with a bigger addition, but it has fallen off a bit from earlier estimates. 

CET from GFS guidance, assuming we are at 4.7 after today (it's 4.5 after 16th), would end up around 6.5, most days looking a bit above average from now to end, with the assumption of an average of 8.5 C for next two weeks, it calculates out to 6.5 C.  

[Summer Sun]

4.5c to the 16th

1.2c below the 61 to 90 average
1.5c below the 81 to 10 average

[Don]

1 hour ago, Roger J Smith said:

EWP now around 60 mm and GFS to end of month says add 40 to that, 100 mm still basically good for the earlier posted scoring. ProlongedSnowLover would be a bit more comfortable with a bigger addition, but it has fallen off a bit from earlier estimates. 

CET from GFS guidance, assuming we are at 4.7 after today (it's 4.5 after 16th), would end up around 6.5, most days looking a bit above average from now to end, with the assumption of an average of 8.5 C for next two weeks, it calculates out to 6.5 C.  

So, even after a cold first half, March could still end up nearly a degree above the 61-90 average!

[The PIT]

Sunny Sheffield at 4C -1.7C below average. Rainfall 83.8mm 138.3% of the monthly total

[Sunny76]

21 hours ago, Don said:

Trouble is cold first halves of months are cancelled out pretty easily by milder second halves these days!

If El Nino develops into a strong east based event, then winter 2023/24 could be over before it begins!

It will be very mild I think. Another 97/98, or 94/95 or possibly an 82/83.

There will be no snow in London or the south that’s for sure next winter.

 

7 hours ago, Quicksilver1989 said:

From November -  January that's when solar radiation is at its minimum so the synoptics don't need to be impressive to get in decent cold. Get a period of clear nights and slack winds and you'll also start getting cold days too regardless of how high T850s are.

Though at this time of the year you'd get warm days followed by chilly days and large diurnal temperature ranges but overall above average temps (unless you got cloudy days and clear nights like in April 2021).

I would say December and March have warmed the most since late 1987.

[Don]

31 minutes ago, Sunny76 said:

It will be very mild I think. Another 97/98, or 94/95 or possibly an 82/83.

There will be no snow in London or the south that’s for sure next winter.

As far as El Nino goes and the affects on winter, it depends on what type, for example a moderate or strong basin wide event would suggest a potentially very mild winter a la 97-98.  However, a weak event or moderate Modiki (central based) event would not necessarily be a bad thing if it's cold you're after, think 09/10.  As for there will be no snow in London or the south next winter that's for sure, you really cannot be serious?!

Edited March 17, 2023 by Don

[Nick L]

1 hour ago, Sunny76 said:

 

There will be no snow in London or the south that’s for sure next winter.

 

An odd and unsubstantiated prediction.

[feb1991blizzard]

8 hours ago, Roger J Smith said:

EWP now around 60 mm and GFS to end of month says add 40 to that, 100 mm still basically good for the earlier posted scoring. ProlongedSnowLover would be a bit more comfortable with a bigger addition, but it has fallen off a bit from earlier estimates. 

CET from GFS guidance, assuming we are at 4.7 after today (it's 4.5 after 16th), would end up around 6.5, most days looking a bit above average from now to end, with the assumption of an average of 8.5 C for next two weeks, it calculates out to 6.5 C.  

This would still give me a shot of pegging it back to 6 or just below.

[Daniel*]

7 hours ago, Don said:

So, even after a cold first half, March could still end up nearly a degree above the 61-90 average!

GFS now going with a much chillier final week to March it’s been behind curve… likely to finish somewhat below 1991-2020 and very close to older baseline I’d say.