May 2021 C.E.T. and EWP forecast contests

[February1978]

11 minutes ago, damianslaw said:

I have similar feeling, been caught out many a time in past going below..  but I think the odds of a below average May are quite high this year unfortunately. I love May, my favourite month, but I'm not feeling the goods this year... all has shades of 2012 and 2013.. general cooler period of 2008-2013.. 2012 produced a wonderful 10 day spellend of month after a dire first two thirds, indeed best spell of the year for sustained warmth and dry sunny weather.. not saying a summer 2012 is on the cards. Much rather have a May 2013 if exchanged for a July 2013.

Agreed, it doesn't look good. I'm usually in Scotland in May, numerous warm sunny weeks, I have my doubts this year though.

2012 - we spent pretty well every Friday wringing out the cricket ground so we could play on Saturday (strangely we generally did play), a seriously wet summer.

[Duncan McAlister]

12C for me please.

[Roger J Smith]

^^ on time forecasts ^^

========================================================

Table of Forecasts for May 2021

 CET _ EWP _ Forecaster _____________________ CET _ EWP _ Forecaster 

res for ______ Lettucing Gutted ( late! ) _______ 11.1 _ ------ _ Typhoon John ( 02 )

12.7 _ 65.0 __ Kirkcaldy Weather ( 12 ) _______ 11.1 _ 90.0 _ sundog ( 42 )

12.5 _ 70.0 __ DiagonalRedLine ( 13 ) ________ 11.1 _ ------ _ damianslaw ( 47 )

12.4 _ 79.0 __ seaside60 ( 50 ) _______________ 11.0 _ 62.0 _ LetItSnow! ( 05 )

12.3 _ 66.0 __ NeilN ( 41 ) ____________________ 11.0 _ 65.0 _ weather-history ( 25 )

12.3 _ ------ __ Man Without Beard ( 53 ) ______ 11.0 _ 95.0 _ rwtwm ( 28 )

_______________________________________________11.0 _ 75.0 _ Blast from the Past (L1-2)

12.1 _ 72.0 __ Stationary Front ( 03 ) _________ 10.9 _ 86.0 _ snowray ( 22,48.5 )

12.0 _ 58.8 __ bobd29 ( 06 ) __________________ 10.9 _ 83.0 _ emmett garland ( 30 )

12.0 _ 69.0 __ General Cluster ( 21 ) __________ 10.9 _ 65.0 _ jonboy ( 33 )

12.0 _ 50.0 __ The PIT ( 26 ) __________________ 10.9 _109.0_ davehsug ( 58 )

12.0 _ 75.0 __ J10 ( 59 ) _______________________ 10.8 _127.2_ Roger J Smith ( 27 )

12.0 _ ------ __ Duncan McAlister ( 61 ) ________ 10.8 _ 91.0 _ Reef ( 40 )

11.9 _ 62.0 __ JeffC ( 16 ) _____________________ 10.8 _ 95.0 _ Frigid ( 45 )

11.9 _ ------ __ Summer Sun ( 17 ) ____________ 10.8 _ 87.4 _ Thundery Wintry Showers ( 56 )

11.9 _ 62.7 __ 1991-2020 average ____________ 10.7 _ 68.0 _ Polar Gael ( 10 )

11.8 _ 31.0 __ Earthshine ( 07 ) ______________ 10.7 _ 77.0 _ Timmytour ( 11 )

11.8 _ 70.0 __ Leo97t ( 18 ) __________________ 10.7 _ 72.0 _ Stargazer ( 24 )

11.8 _ 55.0 __ Summer18 ( 19 ) ______________ 10.7 _ 73.0 _ BornFromTheVoid ( 35 )

11.7 _ 63.6 __ 1981-2010 average ____________ 10.7 _ 84.0 _ noname_weather ( 51 )

11.6 _ 60.0 __ Summer Blizzard ( 09 ) ________ 10.6 _ 64.0 _ SteveB ( 01 )

11.5 _ 57.0 __ WeatherEnthusiast91 ( 15 ) ___ 10.6 _ ------ _ Quicksilver1989 ( 43 )

11.5 _100.0__ DR(S)NO ( 31 ) ________________ 10.5 _ 37.0 _ virtualsphere ( 08 )

11.5 _ 60.0 __ Federico ( 38 ) _________________ 10.4 _ 55.0 _ Relativistic ( 36 )

11.5 _ 75.0 __ Norrance ( 46 ) ________________ 10.4 _ 80.0 _ Walsall Wood Snow ( L1-1 )

11.5 _ 79.0 __ Midlands Ice Age ( 57 ) ________ 10.3 _ ------ _ Kentish Man ( 48 )

11.4 _ ------ __ dancerwithwings ( 23 ) ________ 10.3 _ 96.0 _ daniel* ( 49 )

11.4 _ ------ __ Mark Bayley ( 32 ) _____________ 10.2 _ 40.0 _ B87 ( 04 )

11.4 _ 55.0 __ stewfox ( 37 ) __________________10.2 _101.3_ coldest winter ( 34 )

11.4 _101.0__ Don ( 60 ) ______________________10.1 _ 98.0 _ I Rem Atl 252 ( 14 )

11.3 _ 83.0 _ Feb1991blizzard ( 39 ) ___________  9.9 _168.0_ shillitocettwo ( 20 )

11.3 _ 82.0 _ MrMaunder ( 44 ) ________________ 9.8 _ 80.0 _ syed2878 ( 29 )

11.2 _ 83.0 _ mulzy ( 52 ) _______________________ 9.6 _ 87.0 _ Godber 1 ( 54 )

11.2 _ 81.0 _ February1978 ( 55 ) _______________ 5.9 _ ----- __ Thundershine ( L3-1 )

11.1 _ 75.0 _ consensus 

_ 61 on time forecasts, plus two that are one day late, and one more three days late,

___ 64 in total, consensus (median) 11.1 _ 

 

EWP forecasts in order

168_shil .. 127.2_RJS .. 109_dave .. 101.3_cw .. 101_Don .. 100_DR(S) .. 98_IRem .. 96_ dan* .. 95_rwtwm, Frig ..

 91_Reef .. 90_sun .. 87.4_TWS .. 87_godb .. 86_snow .. 84_non .. 83_eg, feb91,mul .. 82_MrM .. 81_Feb78 ..

 80_syed, WWS^ .. 79_sea,MIA .. 77_tim .. 75_Norr, J10,BFTP^ .. 73_BFTV .. 72_SF, star ..  70_DRL, leo .. 69_GC .. 68_PG ..

 66_NN .. 65_KW, wx-h, jon .. 64_Ste .. 63.6_81-10 .. 62.7_91-20 .. 62_LIS, Jeff .. 60_SB, Fed .. 58.8_bob ..

 57_WxEn .. 55_sum18, Rel, stew .. 50_PIT .. 40_B87 .. 37_virt .. 31_Earth

_ 52 on time forecasts, plus two marked one day late ^, consensus (median) 75.0 mm.

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vVvVv__ late one day __vVvVv

(entries accepted to end of 3rd May, increasing late penalties applied)

Edited May 3, 2021 by Roger J Smith

[Walsall Wood Snow]

Hope I'm not too late. 10.4 c and 80mm please.

[BLAST FROM THE PAST]

I think a relatively cold and fairly wet early part of the month. High pressure again to play it’s part and could be a very warm latter 3rd depending on positioning.

 

11c and 75mm

[Midlands Ice Age]

9 hours ago, Roger J Smith said:

^^ on time forecasts ^^

========================================================

Table of Forecasts for May 2021

 CET _ EWP _ Forecaster _____________________ CET _ EWP _ Forecaster 

res for ______ Lettucing Gutted ( late! ) _______ 11.1 _ ------ _ Typhoon John ( 02 )

12.7 _ 65.0 __ Kirkcaldy Weather ( 12 ) _______ 11.1 _ 90.0 _ sundog ( 42 )

12.5 _ 70.0 __ DiagonalRedLine ( 13 ) ________ 11.1 _ ------ _ damianslaw ( 47 )

12.4 _ 79.0 __ seaside60 ( 50 ) _______________ 11.0 _ 62.0 _ LetItSnow! ( 05 )

12.3 _ 66.0 __ NeilN ( 41 ) ____________________ 11.0 _ 65.0 _ weather-history ( 25 )

12.3 _ ------ __ Man Without Beard ( 53 ) ______ 11.0 _ 95.0 _ rwtwm ( 28 )

12.1 _ 72.0 __ Stationary Front ( 03 ) _________ 10.9 _ 86.0 _ snowray ( 22,48.5 )

12.0 _ 58.8 __ bobd29 ( 06 ) __________________ 10.9 _ 83.0 _ emmett garland ( 30 )

12.0 _ 69.0 __ General Cluster ( 21 ) __________ 10.9 _ 65.0 _ jonboy ( 33 )

12.0 _ 50.0 __ The PIT ( 26 ) __________________ 10.9 _109.0_ davehsug ( 58 )

12.0 _ 75.0 __ J10 ( 59 ) _______________________ 10.8 _127.2_ Roger J Smith ( 27 )

12.0 _ ------ __ Duncan McAlister ( 61 ) ________ 10.8 _ 91.0 _ Reef ( 40 )

11.9 _ 62.0 __ JeffC ( 16 ) _____________________ 10.8 _ 95.0 _ Frigid ( 45 )

11.9 _ ------ __ Summer Sun ( 17 ) ____________ 10.8 _ 87.4 _ Thundery Wintry Showers ( 56 )

11.9 _ 62.7 __ 1991-2020 average ____________ 10.7 _ 68.0 _ Polar Gael ( 10 )

11.8 _ 31.0 __ Earthshine ( 07 ) ______________ 10.7 _ 77.0 _ Timmytour ( 11 )

11.8 _ 70.0 __ Leo97t ( 18 ) __________________ 10.7 _ 72.0 _ Stargazer ( 24 )

11.8 _ 55.0 __ Summer18 ( 19 ) ______________ 10.7 _ 73.0 _ BornFromTheVoid ( 35 )

11.7 _ 63.6 __ 1981-2010 average ____________ 10.7 _ 84.0 _ noname_weather ( 51 )

11.6 _ 60.0 __ Summer Blizzard ( 09 ) ________ 10.6 _ 64.0 _ SteveB ( 01 )

11.5 _ 57.0 __ WeatherEnthusiast91 ( 15 ) ___ 10.6 _ ------ _ Quicksilver1989 ( 43 )

11.5 _100.0__ DR(S)NO ( 31 ) ________________ 10.5 _ 37.0 _ virtualsphere ( 08 )

11.5 _ 60.0 __ Federico ( 38 ) _________________ 10.4 _ 55.0 _ Relativistic ( 36 )

11.5 _ 75.0 __ Norrance ( 46 ) ________________ 10.4 _ 80.0 _ Walsall Wood Snow ( L1-1 )

11.5 _ 79.0 __ Midlands Ice Age ( 57 ) ________ 10.3 _ ------ _ Kentish Man ( 48 )

11.4 _ ------ __ dancerwithwings ( 23 ) ________ 10.3 _ 96.0 _ daniel* ( 49 )

11.4 _ ------ __ Mark Bayley ( 32 ) _____________ 10.2 _ 40.0 _ B87 ( 04 )

11.4 _ 55.0 __ stewfox ( 37 ) __________________10.2 _101.3_ coldest winter ( 34 )

11.4 _101.0__ Don ( 60 ) ______________________10.1 _ 98.0 _ I Rem Atl 252 ( 14 )

11.3 _ 83.0 _ Feb1991blizzard ( 39 ) ___________  9.9 _168.0_ shillitocettwo ( 20 )

11.3 _ 82.0 _ MrMaunder ( 44 ) ________________ 9.8 _ 80.0 _ syed2878 ( 29 )

11.2 _ 83.0 _ mulzy ( 52 ) _______________________ 9.6 _ 87.0 _ Godber 1 ( 54 )

11.2 _ 81.0 _ February1978 ( 55 )

11.1 _ 75.0 _ consensus 

_ 61 on time forecasts, plus one that is one day late, 62 in total, consensus (median) 11.1 _ 

 

EWP forecasts in order

168_shil .. 127.2_RJS .. 109_dave .. 101.3_cw .. 101_Don .. 100_DR(S) .. 98_IRem .. 96_ dan* .. 95_rwtwm, Frig ..

 91_Reef .. 90_sun .. 87.4_TWS .. 87_godb .. 86_snow .. 84_non .. 83_eg, feb91,mul .. 82_MrM .. 81_Feb78 ..

 80_syed, WWS^ .. 79_sea,MIA .. 77_tim .. 75_Norr, J10 .. 73_BFTV .. 72_SF, star ..  70_DRL, leo .. 69_GC .. 68_PG ..

 66_NN .. 65_KW, wx-h, jon .. 64_Ste .. 63.6_81-10 .. 62.7_91-20 .. 62_LIS, Jeff .. 60_SB, Fed .. 58.8_bob ..

 57_WxEn .. 55_sum18, Rel, stew .. 50_PIT .. 40_B87 .. 37_virt .. 31_Earth

_ 52 on time forecasts, plus one marked one day late ^, consensus (median) 75.0 mm.

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vVvVv__ late one day __vVvVv

(entries accepted to end of 3rd May, increasing late penalties applied)

Hey folks what are you doing....   

A first for me.

I'm on the left hand side of the list of entries!

You lot are so fickle!   

MIA

 

[Roger J Smith]

May day, may day, man overboard ...

Checked the 12z GFS run, the CET by about 10th could be no higher than 7.5 to 8.0 (!). It could be struggling into the vicinity of 9 by the middle of the month. If that's the case, all forecasts would need an average 2x as high as their surplus over 9.0 to verify (e.g., an 11.0 forecast would need 13.0 second half, 12.0 would need 15.0 etc). None of those are impossible of course, without checking I would imagine there are some 16-17 CET averages historically for second half of the month. 

The EWP projection on the GFS is around 50 mm by 11th, and maps for 12th to 17th look a bit unsettled with heavy rain developing over France moving towards the North Sea near the end, any change in that could add quite a bit more than the 10 mm I would derive from these maps verbatim, so 60 mm just a rough estimate for the halfway point. If that verified, a lot of our forecasts would need a dry second half but I think that might have been the idea behind quite a few anyway. 

[Roger J Smith]

In before SB even asks me ... coldest running 7th to 16th May CET values of all years that had any values below 9.0 during that interval (presented in reverse chronological order, which includes the coldest of last 10 and 20 years even if they don't qualify that way) ... 2012 dipped to 9.0 by 17th before starting a rapid climb. Before 1980 a year would have to hit a value lower than 8.0 to appear on the list and before 1900 it has to have a value below 7.0 to appear. 

YEAR ____ CET 07 _CET 08 _CET 09 _CET 10 _CET 11 _CET 12 _CET 13 _CET 14 _CET 15 _CET 16 ____ CET end

2019 ____ 8.4 ___ 8.5 ___ 8.6 ___ 8.7 ___ 8.8 ___ 8.9 ___ 9.1 ___ 9.3 ___ 9.4 ___ 9.6 _____ 11.1

2012 ____ 8.2 ___ 8.6 ___ 8.9 ___ 9.3 ___ 9.4 ___ 9.3 ___ 9.3 ___ 9.3 ___ 9.2 ___ 9.1 ______11.7 (was 9.0 on 17th)

2010 ____ 8.7 ___ 8.7 ___ 8.6 ___ 8.4 ___ 8.2 ___ 8.0 ___ 7.9 ___ 7.9 ___ 8.1 ___ 8.1 _____ 10.7

2001 ____ 8.7 ___ 8.8 ___ 9.0 ___ 9.5 ___10.2 __10.8 __11.2 __ 11.3 __ 11.3 __ 11.4 ____ 12.6

1996 ____ 7.1 ___ 7.0 ___ 7.0 ___ 7.0 ___ 7.0 ___ 7.1 ___ 7.2 ___ 7.4 ___ 7.6 ___ 7.4 ______ 9.1

1991 ____ 7.4 ___ 7.7 ___ 7.7 ___ 7.8 ___ 8.0 ___ 8.3 ___ 8.8 ___ 8.9 ___ 8.9 ___ 8.9 _____ 10.8

1985 ____ 8.8 ___ 9.2 ___ 9.3 ___ 9.2 ___ 9.2 ___ 9.2 ___ 9.2 ___ 9.2 ___ 9.3 ___ 9.5 _____ 10.9

1984 ____ 9.8 ___ 9.5 ___ 9.2 ___ 9.2 ___ 9.1 ___ 9.1 ___ 9.0 ___ 9.0 ___ 9.1 ___ 9.2 ______ 9.9

1982 ____ 6.9 ___ 6.9 ___ 7.1 ___ 7.3 ___ 7.5 ___ 8.0 ___ 8.7 ___ 9.1 ___ 9.5 ___ 9.8 _____ 11.6

1981 ____ 8.2 ___ 8.8 ___ 9.1 ___ 9.4 ___10.0 __10.2__ 10.4 __ 10.6__ 10.6 __ 10.7 _____ 11.2

1980 ____ 8.4 ___ 8.3 ___ 8.2 ___ 8.4 ___ 8.8 ___ 9.4 ___10.0__ 10.3__ 10.5 __ 10.7 _____ 11.2

___ only values below 8.0 now qualify (1945 8.0 on 7th warmed very rapidly, left out)

1979 ____ 5.1 ___ 5.7 ___ 6.1 ___ 6.4 ___ 7.0 ___ 7.6 ___ 8.2 ___ 8.7 ___ 9.2 ___ 9.5 _____ 10.0

1967 ____ 7.8 ___ 8.1 ___ 8.4 ___ 8.8 ___ 9.5 ___ 9.9 ___10.1__ 10.1 __ 10.0 __ 10.0 ____ 10.4

1954 ____ 7.8 ___ 8.0 ___ 8.4 ___ 9.2 ___ 9.8 ___10.3 __10.7 __10.8 __ 10.8 __ 10.7 ____ 11.2

1951 ____ 8.4 ___ 8.1 ___ 7.9 ___ 8.0 ___ 8.1 ___ 8.2 ___ 8.3 ___ 8.3 ___ 8.5 ___ 8.5 _____ 10.1

1941 ____ 7.5 ___ 7.2 ___ 7.0 ___ 7.0 ___ 7.0 ___ 7.3 ___ 7.5 ___ 7.7 ___ 7.6 ___ 7.5 ______ 9.4

1932 ____ 7.7 ___ 7.5 ___ 7.3 ___ 7.4 ___ 7.6 ___ 7.9 ___ 8.3 ___ 8.7 ___ 9.0 ___ 9.3 _____ 10.5

1926 ____ 8.4 ___ 8.2 ___ 7.9 ___ 7.9 ___ 8.2 ___ 8.2 ___ 8.3 ___ 8.3 ___ 8.1 ___ 8.0 _____ 10.2

1910 ____ 7.8 ___ 7.6 ___ 7.4 ___ 7.3 ___ 7.3 ___ 7.6 ___ 7.7 ___ 8.1 ___ 8.3 ___ 8.7 _____ 11.2

1902 ____ 7.1 ___ 7.1 ___ 7.0 ___ 6.8 ___ 6.8 ___ 6.9 ___ 6.9 ___ 6.7 ___ 6.7 ___ 6.9 ______ 8.9

___ only values below 7.0 now qualify (1786 7.0 on 8th, warmed steadily to 11.2, left out)

1892 ____ 6.5 ___ 7.0 ___ 7.4 ___ 7.7 ___ 8.1 ___ 8.5 ___ 8.7 ___ 9.1 ___ 9.1 ___ 9.2 _____11.6

1883 ____ 7.2 ___ 7.0 ___ 6.9 ___ 6.7 ___ 6.7 ___ 7.0 ___ 7.5 ___ 7.9 ___ 8.2 ___ 8.6 _____ 10.6

1879 ____ 6.6 ___ 6.4 ___ 6.5 ___ 6.2 ___ 6.4 ___ 6.7 ___ 6.9 ___ 7.0 ___ 7.0 ___ 7.2 ______ 8.9

1877 ____ 5.1 ___ 5.8 ___ 6.4 ___ 6.9 ___ 7.2 ___ 7.5 ___ 7.7 ___ 7.9 ___ 8.1 ___ 8.3 ______ 9.1 

1874 ____ 6.9 ___ 6.8 ___ 6.7 ___ 6.5 ___ 6.7 ___ 6.8 ___ 7.1 ___ 7.4 ___ 7.3 ___ 7.3 _____ 10.0

1861 ____ 7.7 ___ 7.1 ___ 7.0 ___ 7.0 ___ 6.9 ___ 6.9 ___ 7.0 ___ 7.4 ___ 7.8 ___ 8.3 _____ 10.4

1857 ____ 6.1 ___ 6.4 ___ 6.8 ___ 7.2 ___ 7.5 ___ 8.0 ___ 8.6 ___ 9.0 ___ 9.4 ___ 9.7 _____ 11.3

1856 ____ 5.4 ___ 5.6 ___ 5.8 ___ 6.3 ___ 6.8 ___ 7.2 ___ 7.5 ___ 7.6 ___ 7.8 ___ 8.0 ______ 9.4

1855 ____ 6.8 ___ 6.9 ___ 6.8 ___ 7.1 ___ 7.3 ___ 7.2 ___ 7.1 ___ 7.0 ___ 7.0 ___ 7.0 ______ 8.8 

1851 ____ 6.8 ___ 7.3 ___ 7.7 ___ 8.2 ___ 8.4 ___ 8.7 ___ 8.7 ___ 8.7 ___ 8.7 ___ 8.8 _____ 10.4

1850 ____ 6.9 ___ 6.8 ___ 6.8 ___ 7.1 ___ 7.5 ___ 7.6 ___ 7.7 ___ 7.8 ___ 7.7 ___ 7.7 _____ 10.1

1810 ____ 7.0 ___ 7.5 ___ 7.8 ___ 8.1 ___ 8.1 ___ 8.2 ___ 8.2 ___ 8.3 ___ 8.3 ___ 8.4 ______ 9.2

1782 ____ 5.1 ___ 5.2 ___ 5.6 ___ 6.0 ___ 6.3 ___ 6.6 ___ 7.0 ___ 7.2 ___ 7.5 ___ 7.8 ______ 9.0

1773 ____ 6.6 ___ 6.8 ___ 7.1 ___ 7.7 ___ 7.4 ___ 7.3 ___ 7.6 ___ 7.7 ___ 7.8 ___ 8.1 _____ 10.3

_________________________________________________________

(note: 1923, ending up at 9.2, cooled off continuously after mid-month when it was 9.8)

My brain hurts after doing that, overall impressions ...

... what seems like a cold start nowadays was almost normal back around 1850.

... not every cold-ending May CET had any part in this table, 1817 for example was never much

colder than it ended up (8.7). ... only a few of these cold-starting Mays achieved even modest

end of month warmth, the median value for the groups are as follows: 

1980-2020 __ 11.1 (11/41 hit lower than 9.0 at some point 7th to 16th)

1900-1979 __ 10.5 (10/80 hit lower than 8.0 at some point 7th to 16th)

1772-1899 __ 10.1 (15/128 hit lower than 7.0 at some point 7th to 16th)

These median values at end of month average 2.5 C higher than the criterion for inclusion,

which is not a large jump up in CET values, they are always about 1 deg colder than the period average. 

The warmest May to be included in the group is 2001 (12.6 at end). 1945 was 12.2). 

Will be interesting to see if 2021 fits into this group and if so, how far back into the colder past it can compete. 

 

[Roger J Smith]

1981-2010 CET May averages and extremes 1772-2020

 

DATE ____ AVG __ CUM AVG _______ MAX yr ___ MIN yr _______ Running CET extremes

___ 01 ___ 10.6 ___ 10.6 ________16.1 1990,2005 _ 4.2 1866 ____ 16.1 1990,2005_ 4.2 1866

___ 02 ___ 10.4 ___ 10.5 __________ 16.4 1966 __ 3.8 1979 _____ 15.9 1966 ___ 4.1 1979

___ 03 ___ 10.5 ___ 10.5 __________ 17.7 1990 __ 3.1 1877 _____ 16.4 1990 ___ 4.3 1979

___ 04 ___ 10.3 ___ 10.5 __________ 18.0 1834 __ 3.2 1877 _____ 16.8 1990 ___ 4.4 1979

___ 05 ___ 10.6 ___ 10.5 __________ 16.7 1800 __ 4.0 1979 _____ 16.5 1990 ___ 4.3 1979

___ 06 ___ 11.0 ___ 10.6 __________ 18.8 1867 __ 4.4 1831 _____ 16.0 1990 ___ 4.6 1877, 1979

___ 07 ___ 11.0 ___ 10.7 __________ 16.9 2018 __ 4.1 1879 _____ 15.2 1990 ___ 5.1 1782, 1877, 1979

___ 08 ___ 10.9 ___ 10.7 __________ 17.8 2016 __ 2.9 1861 _____ 14.7 1804, 1995 _ 5.2 1782

___ 09 ___ 10.7 ___ 10.7 _______ 17.6 1945,2016 _ 5.7 1837 ___ 14.8 1800 ___ 5.6 1782

___ 10 ___ 10.8 ___ 10.7 __________ 18.2 1959 __ 4.1 1879  ____ 14.7 2008 ___ 6.0 1782

___ 11 ___ 11.1 ___ 10.7 __________ 18.6 2008 __ 4.1 1773  ____ 15.0 2008 ___ 6.3 1782, 1879

___ 12 ___ 11.3 ___ 10.8 __________ 18.8 1945 __ 4.4 1816  ____ 15.1 2008 ___ 6.6 1782

___ 13 ___ 11.6 ___ 10.8 __________ 17.4 1959 __ 5.0 1915  _____ 15.0 2008 ___ 6.9 1879, 1902

___ 14 ___ 11.7 ___ 10.9 __________ 18.8 1992 __ 3.9 1839  _____ 14.9 2008 ___ 6.7 1902

___ 15 ___ 11.7 ___ 11.0 __________ 20.0 1833 __ 4.3 1839  _____ 14.9 1833 ___ 6.7 1902

___ 16 ___ 11.5 ___ 11.0 __________ 20.0 1808 __ 5.2 1996  _____ 15.2 1833 ___ 6.9 1902

___ 17 ___ 11.3 ___ 11.0 __________ 19.7 1833 __ 3.6 1935  _____ 15.4 1833 ___ 7.1 1855, 1902

___ 18 ___ 11.4 ___ 11.0 __________ 19.1 1952 __ 4.1 1872  _____ 15.4 1833 ___ 7.2 1855, 1902, 1996

___ 19 ___ 11.8 ___ 11.1 __________ 20.4 1868 __ 5.2 1872  _____ 15.4 1833 ___ 7.2 1902

___ 20 ___ 12.3 ___ 11.1 __________ 17.8 1916 __ 5.5 1907  _____ 15.4 1833 ___ 7.2 1902

___ 21 ___ 12.1 ___ 11.2 __________ 18.8 1916 __ 5.7 1894  _____ 15.4 1833 ___ 7.2 1902

___ 22 ___ 12.2 ___ 11.2 __________ 19.5 1918 __ 5.0 1867  _____ 15.4 1833 ___ 7.3 1902

___ 23 ___ 12.8 ___ 11.3 __________ 19.5 1922 __ 4.9 1867  _____ 15.5 1833 ___ 7.6 1902

___ 24 ___ 13.3 ___ 11.4 __________ 18.8 1953 __ 5.7 1867  _____ 15.5 1833 ___ 7.9 1902

___ 25 ___ 12.5 ___ 11.4 __________ 21.0 1953 __ 6.5 1814  _____ 15.6 1833 ___ 8.0 1885

___ 26 ___ 12.4 ___ 11.5 ________18.7 1784,2017__4.6 1821_____ 15.5 1833 ___ 8.1 1782, 1885

___ 27 ___ 12.1 ___ 11.5 __________ 19.0 1788 __ 6.6 1984  _____ 15.4 1833 ___ 8.2 1782

___ 28 ___ 12.3 ___ 11.5 __________ 20.6 1847 __ 6.2 1869  _____ 15.3 1833 ___ 8.5 1782, 1885, 1996

___ 29 ___ 12.8 ___ 11.6 __________ 21.2 1780 __ 6.2 1869 _____ 15.2 1833 ___ 8.7 1782,1879,1902,1996

___ 30 ___ 13.1 ___ 11.6 __________ 21.0 1944 __ 4.9 1807 _____ 15.1 1833 ___ 8.7 1817, 1902

___ 31 ___ 13.3 ___ 11.7 __________ 20.5 1947 __ 6.4 1802  _____ 15.1 1833 ___ 8.7 1817#

# 8.7 was lowest during daily data period but 1698 finished on 8.5 and 1740 on 8.6, these could have had lower running CET values at various points before 31st as well. 

See this post a year ago (May 2020 contest thread) for information about when daily CET has exceeded 20.0, all dozen or so cases were before 1953. 

___________________________________________________________________________

1991-2020 daily and cumulative CET values 

date _ mean __ cum ____ date _ mean __ cum ______ date _ mean __ cum ___ date _ mean _ cum

01 ___10.5 ___10.5 _____ 11 ___11.3 ___ 10.9 _____ 21 ___12.5 ___11.3 ____ 31 ___ 13.7 __ 11.9

02 ___10.4 ___10.5 _____ 12 ___11.2 ___ 11.0 _____ 22 ___12.8 ___11.4 ____

03 ___10.1 ___10.3 _____ 13 ___11.4 ___ 11.0 _____ 23 ___13.0 ___11.4 ____

04 ___10.4 ___10.4 _____ 14 ___11.3 ___ 11.0 _____ 24 ___13.4 ___11.5 ____

 

05 ___10.7 ___10.5 _____ 15 ___11.3 ___ 11.0 _____ 25 ___12.8 ___11.6 ____

06 ___11.2 ___10.6 _____ 16 ___11.3 ___ 11.1 _____ 26 ___13.0 ___11.6 ____

07 ___11.6 ___10.7 _____ 17 ___11.3 ___ 11.1 _____ 27 ___13.1 ___11.7 ____

 

08 ___11.5 ___10.8 _____ 18 ___11.7 ___ 11.1 _____ 28 ___13.1 ___11.7 ____

09 ___11.3 ___10.9 _____ 19 ___12.2 ___ 11.2 _____ 29 ___13.2 ___11.8 ____

10 ___11.4 ___10.9 _____ 20 ___12.5 ___ 11.2 _____ 30 ___13.5 ___ 11.8 ____

__________________________

note: these 1991-2020 daily means are similar to 1981-2010 values to about 0.2 warmer, as they end up by monthly average (11.9 vs 11.7). 

these cumulative averages are actually lower than 1981-2010: 1st, 3rd, 4th. Several later ones are equal: 5th to 7th, 15th. 

[Summer Sun]

6.6c to the 1st

2.8c below the 61 to 90 average
4.0c below the 81 to 10 average

___________________________

Current high this month 6.6c on the 1st
Current low this month 6.6c on the 1st

[Midlands Ice Age]

7 minutes ago, Summer Sun said:

6.6c to the 1st

2.8c below the 61 to 90 average
4.0c below the 81 to 10 average

___________________________

Current high this month 6.6c on the 1st
Current low this month 6.6c on the 1st

Wow...

I know we got down to -1.4C last night, but that is a surprise  (not!).

MIA

[Snowyowl9]

May 1996 was certainly very cold and looking at mins also had a thunderstorm on the first must of been a cold one it was just 6c here.

Certainly wintry showers by this day.

Edited May 2, 2021 by Snowyowl9

[Summer Sun]

6.7c to the 2nd

2.7c below the 61 to 90 average
3.8c below the 81 to 10 average

___________________________

Current high this month 6.7c on the 2nd
Current low this month 6.6c on the 1st

[BornFromTheVoid]

First projection for May

 

The chances of finishing:
Close to average (11.4C to 12.4C) is at 19.3% 
Above average (>12.4C) is at 3.2% 
Below average (<11.4C) is at 77.5% 

The period of the 3rd to the 8th is forecast to average 7.6C, 4.0C below the 91-20 average.

[Met.]

Late guess for me: 5.9°C, the coldest on record.

[Godber 1]

I thought my guess 9.6c was low, but 5.9c are you kidding?

[feb1991blizzard]

1 hour ago, Godber 1 said:

I thought my guess 9.6c was low, but 5.9c are you kidding?

I think we can safely rule out anything below 10c already now, looking at somewhere above the high 11's , possibly into the 13's if a late heatwave materialises.

 

EDIT : as for 5.9, that usually busts on the low side for December and sometimes Jan these days, never mind may.

Edited May 3, 2021 by feb1991blizzard

[LetItSnow!]

5 minutes ago, feb1991blizzard said:

I think we can safely rule out anything below 10c already now, looking at somewhere above the high 11's , possibly into the 13's if a late heatwave materialises.

 

EDIT : as for 5.9, that usually busts on the low side for December and sometimes Jan these days, never mind may.

I think under 10 would be a stretch now but still a possibility in the 10s... all in how that low interacts nexts week & what it brings thereafter. I'm personally banking around 10.8-11.6 atm.

[feb1991blizzard]

1 minute ago, LetItSnow! said:

I think under 10 would be a stretch now but still a possibility in the 10s... all in how that low interacts nexts week & what it brings thereafter. I'm personally banking around 10.8-11.6 atm.

hope so as i have gone 11.3 but the average temps look to kick in much earlier this month so they wont be diluted as much, it will lift the cet to average levels by about the 20th i think, you can pretty muuch rule out these kind of temps happening post 20th but you can't rule out very warm, hot or even very hot in the south.

[LetItSnow!]

1 minute ago, feb1991blizzard said:

hope so as i have gone 11.3 but the average temps look to kick in much earlier this month so they wont be diluted as much, it will lift the cet to average levels by about the 20th i think, you can pretty muuch rule out these kind of temps happening post 20th but you can't rule out very warm, hot or even very hot in the south.

if the ECM/UKMO option is to be believed, but GFS is very consistent & I don't think it can be overlooked just yet...

[Roger J Smith]

Not like Craig (LG) to miss a contest, maybe when you make more or less the same forecast every month and usually around the first day it's open you can mistakenly think you already entered by deadline. 

Mind you at this point he would just be triggering me with an ethical dilemma, how to score a forecast with a large late penalty that has a possible score of zero anyway. 

As to that 5.9 forecast, I think you would need a record low every day of the month to get close to that. Back in the Maunder there was a May at 8.5, and 1817 I think had 8.7 in the daily data period. May 1996 was continuously below 10 C to around the 20th and came in at 9.1. 

GFS guidance remains rather cold to 19th, would expect CET to be around 8.5 C by then if it verified, as some mentioned, warmer solutions possible as this block begins to break down gradually. EWP likely to be around 60 mm by then. 

 

[LetItSnow!]

1 minute ago, Roger J Smith said:

Not like Craig (LG) to miss a contest, maybe when you make more or less the same forecast every month and usually around the first day it's open you can mistakenly think you already entered by deadline. 

Mind you at this point he would just be triggering me with an ethical dilemma, how to score a forecast with a large late penalty that has a possible score of zero anyway. 

As to that 5.9 forecast, I think you would need a record low every day of the month to get close to that. Back in the Maunder there was a May at 8.5, and 1817 I think had 8.7 in the daily data period. May 1996 was continuously below 10 C to around the 20th and came in at 9.1. 

GFS guidance remains rather cold to 19th, would expect CET to be around 8.5 C by then if it verified, as some mentioned, warmer solutions possible as this block begins to break down gradually. EWP likely to be around 60 mm by then. 

 

so, you’re saying that, under the guise the GFS is accurate to keep it generally cool up to then, we could potentially have a sub-10C May coming up? if so, who could of saw it coming last year... exciting times but still a long way to go yet. i’m not going overboard just yet!

[Roger J Smith]

I don't think it ends up sub-10 because (a) there's probably going to be some warmish days in the fourth week and (b) the GFS could be over-estimating the duration of the cold anyway. And I'm at 10.8 in the contest so I don't really want sub-10 myself. Would say the chances of it are maybe 20%, 40% in the 10s, 30% in the 11s and 10% in the 12s. Would be quite surprised to see anything higher than 12.2 as an outcome partly from that study I presented of all years that had any significant cold in the second week of May, none of those got much past 11 with one into the low 12s. 

[Roger J Smith]

6 hours ago, Thundershine said:

Late guess for me: 5.9°C, the coldest on record.

Okay I added that to the table, good luck. Without LG in the contest, the highest guess is 12.7 C and the median is 11.1 (64 forecasts). 

I am going to check the contest performance of our consensus (median) now, will report back on that in the April thread. 

[snowray]

3 hours ago, Roger J Smith said:

Okay I added that to the table, good luck. Without LG in the contest, the highest guess is 12.7 C and the median is 11.1 (64 forecasts). 

I am going to check the contest performance of our consensus (median) now, will report back on that in the April thread. 

No LG...hope he’s ok.