GEFS 12z can hardly be described as a washout.  

Don't worry. Any poor runs just end up being a glancing blow to the north west. Not that I like to complain 

Actually all 3.models (ensembles)  are showing a retrogression of the positive height anomalies in Aug and a weakening and a southward shift of the Atlantic trough.

The main question for me if it will be enough to go back to almost the June pattern, but I think most likely is something between that and the current pattern.

An absence of MJO waves would also help as tropical west Pacific convection in summer often contributes to a trough/ridge pattern like this week. 

ECM maintains it's theme of dragging through a shallow daughter low under the main LP which advects the really warm air in the SE and EA. This also has the side effect of stalling the progression of the fronts out west.

Friday 12z:

Small upgrade for the extreme east for Friday 18 uppers thats a >36c chart in any prolonged sunshine for east

Yes Ben slightly more s/e better for heat

GFS 12Z ensembles are the most spread I have seen for a while, but still plenty of hot stuff in there.

Make that 19C uppers. July record would be under threat there.

However ECM is following the GFS in spinning up a much deeper low over Iceland. https://www.theweatheroutlook.com/charts/ecm/120_mslp500.png?cb=52

37C then

Can understand that given the complexities of Friday + weekend. Once that's done and dusted we should get better agreement on the heat potential for early August.

Raw ECM output only says 33C, according to the maps on weather.us.

So add 2, that would give 35C. Still impressive!

Erm, anyone wanna make sense of the ECM run 120-168?  What is that low pressure doing? 

I assume it's going to lift northwards like the 00z?

Perhaps gfs is closer to the mark Rob think you could add one or two on those for Fri/Sat

http://www.weersite.net/?actueel&ensemble&gfs_2m

At 192 the Azores high starts to ridge in.

I seriously doubt the LP will be that deep for the weekend. Mind you it's unusual for ECM to blow up LP's, but it does happen sometimes.

Huge high builds in again by the 2nd , incredibly strong signal for this.

Those are for De Bilt though so hardly representative of British temps.

ECM still solid on building in high pressure from the south by August 3 with high 850s, strong signal for this.

 It says Lat :52 Lon Rob top left

After the dance with the devil words fail me

http://www.wetterzentrale.de/topkarten.php?map=1&model=ecm&var=1&run=12&time=240&lid=OP&h=0&mv=0&tr=24#mapref

For me it says "De_Bilt Lat:52 Lon: 5".

The exact spot 52N 5E is actually a roundabout just outside Utrecht, according to Google Maps: https://www.google.com/maps/place/52%C2%B000'00.0%22N+5%C2%B000'00.0%22E/@51.998206,4.9913893,15.04z/data=!4m5!3m4!1s0x0:0x0!8m2!3d52!4d5

There's a map of all the Met Office stations here. Doesnt look like Boxworth is there any more. Two stations in Cambridge and one at Monks Wood.

https://www.metoffice.gov.uk/public/weather/climate-network/#?tab=climateNetwork

Looking at the likely hottest spots on Friday, it would seem Tobenham or Charsfield could be the hottest - ones I have never seen in the UK maxima lists before. The East Bergholt and Lingwood manual stations could also be late contenders.

Apologies Rob I can see what I have done :Longtiude: thanks for putting us right

https://www.findlatitudeandlongitude.com/?loc=52n+5e&id=2871489#.W1d7qtVKjIU