Met Office Hadley         10.9c.      Anomaly     -0.0c. Provisional to 24th.

Metcheck                      10.80c     Anomaly     -0.16c

Netweather                   11.5c       Anomaly     -0.16c

Mean of my 10 stations   11.74c.   Anomaly    -0.28c.

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Well this month looks like being cool throughout. No real warm up in the second half. In fact the next two days will see the highest positive temperature anomalies of the month and even those are not very impressive and are mainly due to high minimums.

Now looking at potentially a sub 11C month. Current May CET estimate is 10.96C. That would be the coolest May since 2015 and only the fourth time the May CET has been below 11C since 1996.

Expect a significant downward adjustment again this month. Hadley is currently running 0.43C above my estimate.

Crikey!  So the current CET is even worse than it looks!  I am surprised because we really have had some lovely weather this month, although a few frosty nights early on and low night temps all month, so I suspect the minima have kept it down.  Of course this is in my bit of the world and not in a CET area. 

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The strongest late-spring stratospheric warming of the polar vortex on record really made a mess of signal-based long-range estimations this month. Only as we head into June does the resulting high-latitude blocking pattern look to relax sufficiently for the UK to start seeing some appreciably warm temps. Though mainly the blocking just focuses on the Pacific side and so 'leaves room' for ridges across the UK with LP systems moving slowly by to the north.

The patterns therefore look to remain very stagnant, with little sign of the typical resurgence of westerlies in response to the rapidly increasing thermal gradient between the low-mid latitudes and the high latitudes.

 

This raises some very interesting possibilities for June. 

For example, the stagnated plume of the GFS 00z is not at all unrealistic, and gives me a rough CET estimate for the opening 9 days of June that's in the low 17s. As far as I'm aware, while that would not be exceptional for July or August, it's near record territory for June - which really shows how much the 'thermal lag' plus typical return of westerlies tends to peg back the temps in the UK.

 

As the Arctic latitudes warm faster than the lower latitudes, with increasingly early onset of spring heating via snow cover loss, I can see this thermal lag becoming increasingly weak in the decades to come, and as such June could be the summer month that sees the greatest warming trend in the UK and N. Europe generally. 

Given that the days are at their longest, the potential is there for June to become seriously toasty. I'd not be surprised to see (at least) one June CET in the 18s within the next two decades.

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Met Office Hadley         11.1c.        Anomaly      0.1c. Provisional to 25th.

Metcheck                      11.03c       Anomaly      -0.38c

Netweather                   11.34c       Anomaly      0.04c.

Mean of My  10 stations  11.95c.     Difference    -0.07c. 

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Met Office Hadley         11.2c.      Anomaly      0.2c. Provisional to 26th.

Metcheck                      11.13c     Anomaly       -0.28c

Netweather                   11.5c       Anomaly       0.21c

Mean of my 10 stations   12.06c.   Difference   0.4c.

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Met Office Hadley           11.3c.     Anomaly      0.3c. provisional to 27th.

Metcheck                        11.14c   Anomaly       0.62c

Netweather                     11.53c   Anomaly       0.23c.

Mean of my 10 stations     12.03c. Difference    0 1c.

Forest Town Mansfield  11.7c. Anomaly  -1.15  Using a 6-year average.

 

 

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Met Office Hadley         11.3c.     Anomaly     0.3c. Provisional to 28th.

Metcheck                      11.13c    Anomaly     -0.28c

Netweather                   11,54c    Anomaly     0.25c

Mean of my 10 stations 12.03c.  Difference  0.01c.      

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Very interesting to see how this one pans out; tonight and tomorrow night look pretty warm for the time of year right across the CET region; tomorrow and Friday could potentially see some warm days too. Remember it only takes a 20C max and 12C min to give us a 16C CET day- but with only two days to play with, that would give an excess over the current figure of <10, so about .3 in overall terms. IF HadCET is correct (and remember GW suspects it's too high at the moment and will be downjusted) then we'd perhaps end on 11.5-11.6. Still too low for my own bet, but a smaller gap than I'd feared say a week ago.

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Good to see the figure at least holding steady. The cooler weather for this week doesn't seem to be as potent/prolonged as was once forecast. In addition there should be some very mild (even warm) nights coming up which should help nudge the figure higher, despite daytime maxes in the low 20s being hardly notable for late May. It's just a pity May doesn't have 32 days so it could include the very warm/hot temps for Saturday.
But then of course we have the downgrade. It helped me out in April but won't in May. Why does there always seem to be a downgrade, is it simply the correction for the urban heat island effect?

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Month will end on 9.1C (-1.2C) here.

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At time of looking yesterday's CET given as 11.0°C but update for whole month not on site yet. Will be 11.3 or 11.2

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Significant rain for parts of the west over the next 10-day well over 100mm in parts of NW Scotland even the dust bowl south east sees some useful rain

 

Wrong thread Gavin!  

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Significant rain for parts of the west over the next 10-day well over 100mm in parts of NW Scotland even the dust bowl south east sees some useful rain

 

Curbs the CET for a couple of Days.

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Met Office Hadley      11.3c.     Anomaly       0.2c.  Provisional to 29th.

Metcheck                   11.21c.     Anomaly         -0.20c

Netweather                11.54c      Anomaly         0.25c

Mean of my 10 Watched stations  12.09c Difference 0.07c. 

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Wrong thread Gavin!  

 

Oops 

 

It it's seems a weather forum now can't post weather charts in a dedicated thread

 

Bonkers 

 

Oops 

It it's seems a weather forum now can't post weather charts in a dedicated thread

Bonkers 

I just thought it odd to post June rainfall charts in the May CET thread, but if you meant to, that’s my mistake not yours.  

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Met Office Hadley      11.03c.     Anomaly       0.2c.  Provisional to 29th.

Metcheck                   11.21c.     Anomaly         -0.20c

Netweather                11.54c      Anomaly         0.25c

Mean of my 10 Watched stations  12.09c Difference 0.07c. 

Just for clarity, that's 11.3°C. Cheers Art.

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Very interesting to see how this one pans out; tonight and tomorrow night look pretty warm for the time of year right across the CET region; tomorrow and Friday could potentially see some warm days too. Remember it only takes a 20C max and 12C min to give us a 16C CET day- but with only two days to play with, that would give an excess over the current figure of <10, so about .3 in overall terms. IF HadCET is correct (and remember GW suspects it's too high at the moment and will be downjusted) then we'd perhaps end on 11.5-11.6. Still too low for my own bet, but a smaller gap than I'd feared say a week ago.

Nice if it was 11.5C I'd be bang on.

 

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Average now seems cool after so many warm Mays... out of interest does anyone have the highest temp for the month so far and is it the lowest for May for some time as I am kind of thinking it must be given that even 1996 managed to go above 25c at the end ?