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.

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.

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.

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.      

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?

Edited by user 29 May 2019 19:57:09(UTC)  | Reason: Not specified

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

Wrong thread Gavin!  

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. 

Edited by user 31 May 2019 11:31:01(UTC)  | Reason: Not specified

Originally Posted by: Bertwhistle

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.