May 2020 C.E.T. and EWP forecast contests

[summer blizzard]

On May snow in England I have a feeling that there may have been showers in 2010 though probably not settling.

Latest frontal snow round here has fallen in early April 98 and 12. Earliest in Oct 00. Showers in April and October are within memory though.

[damianslaw]

11 hours ago, Scorcher said:

April 26th though, not quite as late as Damien suggested.

Thanks for correcting me, it wasn't the 30th, it was the 28th - I have it in my diary, the snow fell around late morning.

[Thundery wintry showers]

Snow in May has been rare since the widespread instance on 6/7 May 1997, with only one fairly widespread instance since then, on 11 May 2010 from the Midlands northwards.  Localised snowfalls happened though as recently as 4 May 2019 from a northerly air stream, when there were scattered reports of sleet and snow in the heavier showers near the east coast.  It was a lot more common up until and including 1997.  The first week of May 1979 was probably the most famous example of the past half-century, and snow showers fell in places early in the Mays of 1982 and 1987, and even in some parts during the second week of May 1989, during an otherwise warm sunny month.  In the 1990s sleet and snow fell quite widely in the Mays of 1993 and 1995 as well as 1997, and more locally in the very cold May of 1996.  Manchester Airport reported sleet or snow falling on 12 May 1995 as well as 6 and 7 May 1997.

Edited May 11, 2020 by Thundery wintry showers

[Summer Sun]

11.8c to the 10th

1.5c above the 61 to 90 average
1.1c above the 81 to 10 average

___________________________

Current high this month 11.9c to the 9th
Current low this month 9.8c to the 1st

[summer blizzard]

Stormchaser in the other realm estimated 9.9C to the 17th i believe however i'd imagine that would be too low even with the cool uppers. 

[Roger J Smith]

EWP looking very similar to last month, 7 mm to date (est 1 mm yesterday) and only 2-3 mm more predicted in next ten days, so around 10 mm as late as 21st.

Then it starts to look more unsettled days 11-16 of GFS and could imagine 15-25 mm added by 27th (total 25-35 mm). 

As for CET, would agree unlikely to go below 10.5 at coldest point late this week, then will recover gradually towards 12 C next week. 

To get from yesterday's 11.8 to a predicted 9.9 on 17th requires something like an average of 7 C, seems a bit low with any sunshine days will likely average 8-9 C. 

Very wet down in southwest France, some locations near Bordeaux have seen 75-100 mm rainfalls in past day. 

[damianslaw]

10 hours ago, Summer Sun said:

11.8c to the 10th

1.5c above the 61 to 90 average
1.1c above the 81 to 10 average

___________________________

Current high this month 11.9c to the 9th
Current low this month 9.8c to the 1st

Mmm surprised it didn't drop a 0.1 or 0.2 degree lower than that yesterday, the warm air I thought had been swept out of the CET zone yesterday, I'm expecting this current chilly spell will result in some marked downward corrections, as this has often happened in recent months when there has been a notably cool spell, underestimates of minima.

[snowray]

14 hours ago, damianslaw said:

Mmm surprised it didn't drop a 0.1 or 0.2 degree lower than that yesterday, the warm air I thought had been swept out of the CET zone yesterday, I'm expecting this current chilly spell will result in some marked downward corrections, as this has often happened in recent months when there has been a notably cool spell, underestimates of minima.

The milder air on Sunday did hang on for longer than expected, there were temps widely in the mid/high teens in the morning in the south and also some parts of the Midlands, it was glorious around here until early afternoon although my location is not in the CET zone. 

Last night saw some very low temps, 0/-1c generally but I see that Benson got down to -4c, should see a fair old drop this week, followed by a steady rise thereafter. 

Edited May 12, 2020 by snowray

[Roger J Smith]

I'm sure Summer Sun will have the daily update but I already peeked at the data, Monday averaged 6.9 C and the running mean dropped to 11.4. 

So it took two days but there was a temperature drop of almost ten degrees over those two days. 

[Relativistic]

3 hours ago, snowray said:

The milder air on Sunday did hang on for longer than expected, there were temps widely in the mid/high teens in the morning in the south and also some parts of the Midlands, it was glorious around here until early afternoon although my location is not in the CET zone. 

Last night saw some very low temps, 0/-1c generally but I see that Benson got down to -4c, should see a fair old drop this week, followed by a steady rise thereafter. 

Figure I saw was -3.6C. The May record is -9.4C, so in one sense this is equivalent to -21C in the Winter months. Pretty impressive!

[cheeky_monkey]

sunny Edmonton stands at 7.8c to May 11th which is 3.7c below normal thus far

[The PIT]

Sunny Sheffield down to 10.8C +1.3C above normal. rainfall unchanged.

From Thursday it should stop falling and possibly start rising again.

[damianslaw]

4 hours ago, cheeky_monkey said:

sunny Edmonton stands at 7.8c to May 11th which is 3.7c below normal thus far

You seem to be having a cold year so far, only part of northern hemisphere that seems to be recording colder than average conditions.

[cheeky_monkey]

1 hour ago, damianslaw said:

You seem to be having a cold year so far, only part of northern hemisphere that seems to be recording colder than average conditions.

Not unusual for this part of the world..we rarely get average months..what tends to happen is we get long runs of above average months followed by long runs of below average months

[Dancerwithwings]

3 minutes ago, cheeky_monkey said:

Not unusual for this part of the world..we rarely get average months..what tends to happen is we get long runs of above average months followed by long runs of below average months

Perfect place for me as I love extremes

[damianslaw]

1 hour ago, cheeky_monkey said:

Not unusual for this part of the world..we rarely get average months..what tends to happen is we get long runs of above average months followed by long runs of below average months

We just seem to get long runs of either average or more often above average months with a few slightly below average months scattered in the mix. Long periods of below average months seem hard to achieve now, but no doubt well break the mold when least expected.

[Summer Sun]

11.0c to the 12th

0.5c above the 61 to 90 average
0.2c above the 81 to 10 average

___________________________

Current high this month 11.9c to the 9th
Current low this month 9.8c to the 1st

[The PIT]

Sunny Sheffield down to 10.5C +0.8C above average. Rainfall unchanged.

[Roger J Smith]

The EWP to now is stuck on 6 mm, and the ten day projections remain low, no more than 10 mm over the grid. Days 11 to 16 of the 06z GFS run showed perhaps 15-20 mm additional by 29th and the most likely evolution of the final map to the 31st suggested 2-5 mm. That all adds up to only 40 mm at most, so predictions in the range 30-40 seem to have best chances. Having said that, the projections do show much heavier rainfalls as close as western Ireland over the ten day interval so there may be a fairly significant uncertainty factor involved.

As the lowest forecast is 30 mm, I will set that as the provisional for an idea of scoring projections. Then if at any point we get reliable indications of an outcome higher than 30 mm I can adjust that provisional going forward. Look for a summary of projected annual scoring based on 30 mm later today. The ten lowest forecasts we had were:

The PIT _____ 30 mm

I Rem Atl252 _ 31 mm

Earthshine ___ 32 mm

Feb91Blizzard_ 41.2 mm

Polar Gael ___ 45 mm

Reef ________ 46 mm

weather-history _ 47 mm

Let It snow! ____ 47 mm

JeffC _________ 48 mm

virtualsphere ___ 48  mm

With 51 forecasts the scoring is very simplified, 50 scoring levels 0.2 apart, except that later entries will only fall by 0.1, so for these ten, the scores would start at 10.0 and work down to 8.3. 

The lowest three forecasts are close enough that I would say they probably have about equal chances of taking the top spot.

Since the next set of forecasts after 48 mm are at 55 mm, that means 42.5 mm or lower guarantees this would be the top ten in some order.

Back in a while with the projected annual update. Once again, quite a few of these top contenders are from the middle or lower thirds of the scoring (for regular entrants) and that will perhaps lead to a more crowded leaderboard although evidently Reef will be moving ahead. 

 

 

 

[Roger J Smith]

 

PROVISIONAL EWP CONTEST ANNUAL SCORING UPDATE (based on 30 mm outcome)

 

Note for outcomes closer to 40 mm, those in red type may move down a few ranks or by 1.0 points, and those in blue would move up slightly, anyone else who predicted over 50 mm unlikely to see any changes unless the projections are way off. This table includes everyone who participated in May plus a few higher ranked non-participants who have an asterisk beside their annual update (same score as after April).

RANK __ prev ___ FORECASTER ___ Points _________ RANK __ prev ___ FORECASTER ____ Points

01 _____ 01 ____ Reef _____________48.75 __________ 31 _____ 16 ____ Relativistic _______ 28.65

02 _____ 02 ____ Emmett Garland ___ 47.15 ___________32 ____ 13 ____ Robbie Garrett _____28.74*

03 _____ 03 ____ Twilight __________  41.88 __________ 33 ____ 24 ____ Dog Toffee ________ 28.62

04 _____ 04 ____ Godber1 __________41.57 __________ 34 ____ 33 ____ daniel* ___________ 27.96

05 _____ 05 ____ Mulzy ____________40.37 ___________ 35 ____ 41 ____DiagonalRedLine ___27.27

06 _____ 06 ____ mb018538 ________37.04 ___________ 36 ____ 36 ____ February1978 _____ 27.00

07 _____ 08 ____ Don _____________ 35.74 ___________ 37 ____ 26 ____ Weather26 _______ 26.80

08 _____T11____ General Cluster____ 35.63 ____________38 ____ 27 ____ Roger J Smith _____26.31

09 _____ 22 ____ virtualsphere ______ 34.84 ____________39 ____ 49 ____ weather-history ____26.23

10 _____ 18 ____ snowray __________34.15 ____________40 ____ 24 ____ Kentspur _________25.65*

11 _____ 30 ____ DAVID SNOW _____ 33.53 ____________41 ____ 53 ____ I Rem Atl 252 _____ 25.58

12 _____ 07 ____ Thundery Wintry Sh _33.25* ___________42 ____ 39 ____ CheesepuffScott ___ 24.80 

13 _____ 32 ____ Jeff C ____________33.22____________ 43 ____ 57 ____ Polar Gael ________ 21.86

14 _____ 37 ____ The PIT __________ 32.37 ____________44 ____ 44 ____ Kirkcaldy Weather __ 21.47

15 _____ 19 ____ brmbrmcar ________32.25 ____________ 45 ____ 47 ____ prolongedSnowLover 21.21

16 _____ 34 ____ seaside60 ________ 32.06 ____________ 46 ____ 38 ____ syed2878 ________ 21.08*

17 _____ 09 ____ Timmytour ________31.81 ____________ 47 ____ 52 ____ Norrance _________ 20.92

18 _____ 31 ____ SteveB ___________31.50 ____________ 48 ____ 43 ____ stargazer _________ 20.49

19 _____ 20 ____ J10 ______________31.41 ____________ 49 ____ 54 ____ NeilN ____________19.91

20 _____ 38 ____ Midlands Ice Age ___31.30_____________50 ____ 42 ____ Radiating Dendrite __19.83*^

21 _____ 15 ____ Stationary Front ____31.15 ____________ 51 ____ 61 ____ Let It Snow! _______ 19.02

22 _____T11____ Bobd29 __________ 31.03 ____________ 52 ____ 45 ____ Mr TOAD _________18.99**

23 _____ 21 ____ davehsug ________ 30.67 _____________53 ____ 46 ____ shillitocettwo _______18.80

24 _____ 14 ____ DR(S)NO ________ 30.49 _____________54 ____ 48 ____ freeze ____________17.75*

25 _____ 17 ____ Blast from the Past_ 30.22 ____________ 55 ____ 51 ____ B87 ______________16.92

26 _____ 25 ____ Mr Maunder ______ 30.00_____________56 ____ 49 ____ pinball wizard ______16.74**

27 _____ 35 ____ Born from the Void _ 29.98____________ 59 ____ 118 ____Earthshine ________11.50^

28 _____ 10 ____ jonboy __________ 29.78* ____________63 ____ 109 ___ summer blizzard ____10.40^

29 _____ 40 ____ Feb1991Blizzard __29.68_____________ 65 ____ 109 ___ coldest winter ______10.19**

30 _____ 23 ____ SLEETY _________28.89 ____________114 ____ 131 ___ Leo97t ____________ 2.44^

________________________________________________ 130 ____ 129 ___ Lettucing Gutted ____  0.51

_____________________________________________________________________________________

* from four or five contest entries and did not enter May (some others did enter May and have 4, 5 entries)

** from three contest entries (Mr TOAD, pinball wizard did not enter May, coldest winter did enter May)

^ from two contest entries and entered May ( *^ Rad D had two and did not enter May)

This table will be adjusted if the provisional heads to any number higher than 36 mm ... that would bring about

minor changes with the blues possibly moving up slightly and the reds down slightly (in points at least). 

A more major revision might be necessary if the provisional begins to move into high 40s or low 50s.(mm rain).

 

 

Edited May 13, 2020 by Roger J Smith

[Summer Sun]

10.8c to the 13th

0.1c above the 61 to 90 average
Bang on the 81 to 10 average

___________________________

Current high this month 11.9c to the 9th
Current low this month 9.8c to the 1st

[The PIT]

Sunny Sheffield down to 10.2C +0.4C above normal. Rainfall unchanged.

An unexpected return to very mild conditions to day so questionable whether there will be much of drop tomorrow before rising again.

[Roger J Smith]

Higher CET guesses are looking good now with two weeks of fairly warm weather ahead (according to GFS anyway). Would estimate a slow but steady climb to around 13 for CET by last few days of month, could fall back slightly at end if those maps verified, so would say 12.5 the over/under at present; EWP still looks headed for a rather low total around 30 mm. 

[damianslaw]

Another drop expected tomorrow and most probably the low point, a marked warm up then taking place from weekend onwards. 

[The PIT]

Sunny Sheffield down to 10.1C +0.2C above normal. Rainfall unchanged.

So really back to normal. Will need around 20C to stop another drop for today which is unlikely.