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

[Summer Sun]

5.6c to the 1st

0.1c below the 61 to 90 average
0.6c below the 81 to 10 average

[damianslaw]

A cold start to the month on the cards, possibly significantly colder than average if the current models as forecast verify. We've had very cold starts to March in recent year, 2018 being a notable case! - though the cold retreated quickly... but then came back. I think the last time we had a predominantly cold first half to March was 2016.. not exceptionally so. March 2013 unusually delivered its coldest conditions second half, though the first half was still notably cold, we had an ice day on the 11th.. 

Other cold starts to March include 1996, 1998 (not significantly so and didn't last), 2001 - severe frosts, 2005 and 2006 - indeed 2006 was very cold until the final third of the month, 2010 as well.

Good to keep a running track how we compare with 1996, 2001, 2006, 2010, 2013 and 2016 in the week ahead. Perhaps a stastical quirk but there a near pattern here, of cold Marches every 5 years, 1996, 2001, 2006, (2010 - just 4 years, 2013, 7 years - not quite but not far off), 2018, now 2023 I wonder!

Edited March 2, 2023 by damianslaw

[summer blizzard]

2011 was a suprise, if anything i remember it for a heatwave late on which no doubt led into April. 

[LetItSnow!]

If we do get a cold March it puts on a similar temperature pattern to early 1995, though perhaps a rather useless analogue since the actual months contained quite different conditions - nonetheless, interesting. March 1995 was a whole degree colder than February 1995.

[damianslaw]

52 minutes ago, LetItSnow! said:

If we do get a cold March it puts on a similar temperature pattern to early 1995, though perhaps a rather useless analogue since the actual months contained quite different conditions - nonetheless, interesting. March 1995 was a whole degree colder than February 1995.

In the historic thread I have referenced March 1995, there was a notably wintry first week or so, we had a cold northerly late month as well.

[Summer Sun]

5.4c to the 2nd

0.3c below the 61 to 90 average
0.5c below the 81 to 10 average

[Don]

2 hours ago, Summer Sun said:

5.4c to the 2nd

0.3c below the 61 to 90 average
0.5c below the 81 to 10 average

Below average, not something you see too often these days!

[Summer Sun]

5.0c to the 3rd

0.6c below the 61 to 90 average
0.1c below the 81 to 10 average

[ItNeverSnowsInWindsor]

Not that much below average considering the synoptics ?

[Roger J Smith]

33 minutes ago, prolongedSnowLover said:

Not that much below average considering the synoptics ?

It will of course drop lower this coming week, but also as you may know the reporting in v2.0 from Met Office has changed from the old era, and from our custom here (1981-2010), to report against running means. The Met Office is reporting differentials of today's average vs end of month 1961-90 averages. 

I don't know why they changed and my opinion is that the old way was better and more logical. After all, March is a month that in most cases warms gradually as our 1981-2010 tracking (in my post late March 1st or early 2nd) illustrates, the end of month normal is 6.6 so we are 1.6 below that. And 1991-2020 is 6.7 (a whisker below 6.8 after rounding) so we are 1.7 below that end of month value.

In terms of what you said, it means we are probably above the 1961-90 running CET value, I will calculate that some time during the coldest part of the period ahead just for fun. 

[damianslaw]

40 minutes ago, prolongedSnowLover said:

Not that much below average considering the synoptics ?

The synoptics so far have been high pressure just to the NW, producing a flow off the N Sea and lots of cloud - maxima have been supressed, but minima not so, only patchy frost. Tomorrow sees colder uppers in from the north, but it won't be until Tuesday these sweep fully though the UK.

Edited March 4, 2023 by damianslaw

[Roger J Smith]

EWP update, 1.2 mm to date, looking at 40-45 mm by 20th according to GFS guidance. Northern England closer to 70-80 mm.

CET forecast, will drop to about 3,0 or a bit lower by 10th, with snow coming and going near end of that cold spell, then a rather steady rise by about 0.5 per day for several days, levelling off eventually around 6 C. (this covers period to 20th, from 6.0 on 20th a cool regime would lead to an outcome around 5.5 possibly, and another warm spell like the one predicted for mid-month could push it to 7.0 or a bit higher. Would say most CET forecasts still safe at this point. 

[damianslaw]

1 hour ago, Roger J Smith said:

EWP update, 1.2 mm to date, looking at 40-45 mm by 20th according to GFS guidance. Northern England closer to 70-80 mm.

CET forecast, will drop to about 3,0 or a bit lower by 10th, with snow coming and going near end of that cold spell, then a rather steady rise by about 0.5 per day for several days, levelling off eventually around 6 C. (this covers period to 20th, from 6.0 on 20th a cool regime would lead to an outcome around 5.5 possibly, and another warm spell like the one predicted for mid-month could push it to 7.0 or a bit higher. Would say most CET forecasts still safe at this point. 

A bone dry start to March here, tomorrow might bring a shower or two, and next week could see copious precipitation in the form of snow and rain.. we shall see..

[Don]

1 hour ago, Roger J Smith said:

EWP update, 1.2 mm to date, looking at 40-45 mm by 20th according to GFS guidance. Northern England closer to 70-80 mm.

CET forecast, will drop to about 3,0 or a bit lower by 10th, with snow coming and going near end of that cold spell, then a rather steady rise by about 0.5 per day for several days, levelling off eventually around 6 C. (this covers period to 20th, from 6.0 on 20th a cool regime would lead to an outcome around 5.5 possibly, and another warm spell like the one predicted for mid-month could push it to 7.0 or a bit higher. Would say most CET forecasts still safe at this point. 

Yes, remember March 2005 had a cold and wintry start but overall had a mild CET of 7.2C.

[damianslaw]

7 minutes ago, Don said:

Yes, remember March 2005 had a cold and wintry start but overall had a mild CET of 7.2C.

Quite a tall order to see cold sustain itself from start of month to the end in March. 2013 started off mild and became progressively colder unusually, but recent cold starts to March in 1996, 2001, 2005, 2006, 2010 and 2018 brought a warming trend especially during the last third.

2006 was close to delivering an exceptionally cold March, but the last week was very mild indeed. Bit of a forgotten month for cold that one, the first 20 days felt like the depths of winter here, 2001 similiar to an extent as well.

Edited March 4, 2023 by damianslaw

[Summer Sun]

4.9c to the 4th

0.8c below the 61 to 90 average
0.1c below the 81 to 10 average

[Roger J Smith]

Note: Hadley EWP tables finally updated, JAN confirmed 97.8 mm, FEB now 16.5 mm. Further details in February thread, all EWP scoring posts now updated to reflect these changes. 

[damianslaw]

7 hours ago, Summer Sun said:

4.9c to the 4th

0.8c below the 61 to 90 average
0.1c below the 81 to 10 average

Could well be in the 3s in a few days time, by Friday, notably low minima Tues and Wed will have a major effect, making for a cold first 10 days to March at least.

[The PIT]

Sunny Sheffield at 4.7C  -0.4C below average. Rainfall 1.5mm 2.5% of the monthly average

[Summer Sun]

4.7c to the 5th

1.0c below the 61 to 90 average
0.2c below the 81 to 10 average

[The PIT]

Sunny Sheffield still at 4.7C -0.5C below average. Rainfall 1.9mm 3.1% of the monthly average

[Summer Sun]

4.6c to the 6th

1.1c below the 61 to 90 average
0.6c below the 81 to 10 average

[Roger J Smith]

EWP update, about 6 mm to date, and still looking at 40-45 mm more by 23rd according to GFS guidance. Northern England and parts of Wales closer to 80-100 mm. Southwest also above the national grid average. Large parts of central England and southeast a bit below. EWP likely to be around 50 mm by 23rd if this guidance correct (confidence rather low, a lot of upside risk on that).

CET forecast ... still think it will drop to about 3,0 or a bit lower by 10th or 11th, with snow coming and going, then a rather steady rise by about 0.5 per day for several days, levelling off eventually around 6  to 6.5 C. (this covers period to 23rd, from 6.3 on 23rd a cool regime would lead to an outcome around 5.7 possibly, and another warm spell like the one predicted for mid-month could push it to 7.5 or a bit higher. Would say the coldest third of CET forecasts need the warmer trends to be cut back  at this point. Middle third could use a cool turn at end of month if all goes to plan. Upper third need the warmth to linger.

 

[damianslaw]

5 hours ago, Roger J Smith said:

EWP update, about 6 mm to date, and still looking at 40-45 mm more by 23rd according to GFS guidance. Northern England and parts of Wales closer to 80-100 mm. Southwest also above the national grid average. Large parts of central England and southeast a bit below. EWP likely to be around 50 mm by 23rd if this guidance correct (confidence rather low, a lot of upside risk on that).

CET forecast ... still think it will drop to about 3,0 or a bit lower by 10th or 11th, with snow coming and going, then a rather steady rise by about 0.5 per day for several days, levelling off eventually around 6  to 6.5 C. (this covers period to 23rd, from 6.3 on 23rd a cool regime would lead to an outcome around 5.7 possibly, and another warm spell like the one predicted for mid-month could push it to 7.5 or a bit higher. Would say the coldest third of CET forecasts need the warmer trends to be cut back  at this point. Middle third could use a cool turn at end of month if all goes to plan. Upper third need the warmth to linger.

 

The mid month warm up looking fragile I say... we could be struggling to get out of the 5s by the time we hit the last third of the month. Anyhow the next few days will see a nosedive in the CET. 

[LetItSnow!]

A cold March is by no means guaranteed, but for interest's sake I took a look at notably colder Marches following mild Februaries since 1900 and there's not a whole lot.

March 1908 (5.3 vs 4.3)

March 1937 (5.6 vs 3.6)

March 1946 (5.9 vs 5.1)

March 1949 (5.7 vs 5.1)

March 1980 (5.8 vs 4.7)

March 1995 (6.5 vs 5.5)

And for more novelty's sake, here's some analogues for the springs and summers that follow.

 A fairly warm and dry April.

Possibly a very warm May but thundery for the south, ala 2018.

Quite a mixed and unsettled June with probably near-normal temperatures.

One of those July's that's probably cool, wet and dull for England but dry and fine for Scotland.

Similar for August but probably drier and sunnier but still cool due to the presence of a Euro trough. Probably gorgeous for Scotland and dull for England (1978 and 2021 spring to mind).

 

Any excuses to bring out the data with me