This thread is for all comments, discussion, and analysis of temperatures in the UK during May, with particular emphasis on the Central England Temperature (CET), for the simple reason that it is the longest-running temperature series in the world with over 360 years of data. But you can comment on any interesting temperature statistics or data from across the UK, including your own backyard.  

For those taking part in the competition, all CET predictions for May should be sent directly to me via the forum private message system. Please do not post them directly into the thread.      

Historic CET summary for May

1981-2010 (30 years) 11.66C

1991-2020 (30 years) 11.90C

2001-2020 (20 years) 12.02C

Last May was fairly chilly with a CET of just 10.1C. Prior to that 4 of the previous 5 years saw a CET above 12C with the highest being 13.3C in 2018.   

Here is a chart of the May CET for all years since 1961  

Direct link to a larger version of the chart

Current model output     

GEFS - the extended run from 0z on 30 April shows the GEFS mean above average every day from the 4th. That is very unusual and suggests a good chance of a fairly warm month.

https://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gfs&var=2&run=99&lid=ENS&bw= 

https://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gfs&var=5&run=99&lid=ENS&bw=

ECM (for de Bilt) shows a rather cool first week with something potentially warmer after that. Lots of scatter by the middle of the month but one or two runs do reach 30C surface temperature. The control run stays average / cool though.   

https://www.weerplaza.nl/gdata/eps/eps_pluim_tt_06260.png

Met Office contingency planners outlook    

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/3moutlook-mjj-v2.pdf

No one month summary this time. Really strange that Met O sometimes has a one month and 3 month summary in the contingency planners outlook and sometimes just has a 3 month summary. The 3 month outlook suggests only a 10% chance of cool weather. Rainfall shows little deviation from average in terms of probability. Very little narrative commentary this month.

Met Office Hadley       10.9c       Anomaly       1.5c provisional to 1st

Metcheck                    10.39c     Anomaly        -1.02c

Netweather                 11.03c     Anomaly        -0.28c

Peasedown St John     9.6c     Anomaly     -2.0c.

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Met Office Hadley     11.4c     Anomaly    2.0c provisional to 2nd

Metcheck                  10.81c   Anomaly    -0.60c

Netweather               11.47c   Anomaly    0.18c

Peasedown St John   10.2c   Anomaly   -1.4c.

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It will be interesting to see the predictions for this month. I have gone for a warm/hot May at over 13c

Ive a feeling this month and June are going to be the best months of the summer season.

It will be interesting to see the predictions for this month. I have gone for a warm/hot May at over 13c

Ive a feeling this month and June are going to be the best months of the summer season.

 

I've gone for 'warmish', but am already thinking it's going to be too low (and I'm sure I'll be near the bottom of the prediction pile)

 

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I've gone for 'warmish', but am already thinking it's going to be too low (and I'm sure I'll be near the bottom of the prediction pile)

 

I've gone for 12.0C reckon I might have gone too low now.

Just looked up - The all time record for May is 15.1C in 1833.

In some ways I reckon that's ripe for picking.

 

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I've gone for 'warmish', but am already thinking it's going to be too low (and I'm sure I'll be near the bottom of the prediction pile)

 

Me too and I already have the same worry as you. Even chilly Stonyhurst is looking quite warm with mild nights - which is often the crucial factor. Of course, model output and forecasts can change quite quickly so still very early days

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The May and June record are both ripe for picking.
Both pre 20th century artefacts now and with modern background warming and the same kind of synoptics they would surely be blown out of the water

The outlook can change quickly of course but atm it looks very warm.  Wonder if anyone went for 14c+?

 

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Met Office Hadley       11.4c      Anomaly       1.9c provisional to 3rd

Metcheck                    10.73c    Anomaly       -0.67c

Netweather                 11.37c    Anomaly       0.08c

Peasedown St John    10.97c     Anomaly     -0.63c.           

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Mey Office Hadley       11.7c      Anomaly     2.0c provisional to 4th

Metcheck                     10.77c   Anomaly      -0.64c

Netweather                  11.51c   Anomaly      0.21c

Peasedown St john     10.74c    Anomaly     -0.86c.

  

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The May and June record are both ripe for picking.
Both pre 20th century artefacts now and with modern background warming and the same kind of synoptics they would surely be blown out of the water

18.2C For June - which was in 1846. That's quite a nut to crack. But these days almost anything is possible.

 

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17C in 1976 is really quite a long way off that and it remains our benchmark for hot Junes. September 2006 at 16.8C was hotter than any June since
The mega June which starts hot and stays hot, perhaps with a few thundery interludes and muggy nights to inflate the minima, is surely coming at some point....

Met Office Hadley       11.9c     Anomaly     2.1c provisional to 5th

Metcheck                    11.26c   Anomaly     -0.14c

Netweather                 11.81c   Anomaly     0.52c

Peasewdown  St John   11.72c    Anomaly     1.12c.        

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Met Office Hadley        12.1c     Anomaly      2.2c provisional to 6th

Metcheck                     11.62c   Anomaly      0.22c

Netweather                  12.13c   Anomaly      0.84c

Peasedown St John      11.95c     Anomaly     0.35c.        

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17C in 1976 is really quite a long way off that and it remains our benchmark for hot Junes. September 2006 at 16.8C was hotter than any June since
The mega June which starts hot and stays hot, perhaps with a few thundery interludes and muggy nights to inflate the minima, is surely coming at some point....

After December 2015 and the ease of which we are recording above average CETs, there's a few months that I think are bound to smash their records at some point.

March is one... the record is 9.2, and considering we had a December of 9.7, I think a double figure March is well within the realm of possibilty.

May is another. The record is 15.1 (I think), yet recently we seem to stall in the low 13s. It's only a matter of time before that is smashed.

October as well...

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Yep
Oct 2001 was a really lacklustre record breaker aswell being mostly dull and wet with some flooding in places. I remember being surprised to hear on the news that it had beaten the CET record (this competition not being a thing then )... It was mainly the minima that pushed it past the much more pleasant month in 1995 .
Would be good to see a sunny and dry one take its place

Met Office Hadley      12.3c       Anomaly      2.3c provisional to 7th

Metcheck                   11.69c     Anomaly      0.28c

Netweather                 12.33c    Anomaly      1.04c

Peasedown St John     12.2c     Anomaly     0.6c.

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After December 2015 and the ease of which we are recording above average CETs, there's a few months that I think are bound to smash their records at some point.

March is one... the record is 9.2, and considering we had a December of 9.7, I think a double figure March is well within the realm of possibilty.

May is another. The record is 15.1 (I think), yet recently we seem to stall in the low 13s. It's only a matter of time before that is smashed.

October as well...

I agree- though not necessarily with the same months. With a 9.7C December,November should surely be able to manage 2 degrees up on that- the feeble 10.1 in 1994 is only a tad up on the December record. But 15 in May and 18 in June will be very hard nuts to crack, I reckon. A July 20+ is more likely.

That said, only 1994's November was warmer than Dec15, reflecting how totally exceptional that month was.

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I can see a 14.0C coming out of the likes of the next two weeks.

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