Arôme gives us 31C in East London tomorrow. 21C at 7am on Friday (only goes that far).

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I've a feeling that Heathrow is one of the few automated forecasts that also receives human input hence increased reliability. They are adding human input to many more sites for the Met Office App in the near future so it should be much more reliable.

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MetOffice app now only showing 37C

Oh no; only 37. I don't think I can bear the disappointment. 

Just another day then.

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Oh no; only 37. I don't think I can bear the disappointment. 

Just another day then.

Ha, I realised after I wrote that how stupid it sounded.

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IPhone app has now joined the MetOffice app on 37C.

BBC lagging behind at 35C.

37C seems to be the form horse.

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It’s crazy to think it took 16 years to reach 100F again after 2003.

We then reach 100F again just over a year later.

We are potentially going to hit it again a week after that.

Unbelievable really.

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Week ahead BBC at 955 had max of 34 Fri and my phone app say 33 for Heathrow now Fri and down to 28 by Sat and cooler Sunday

Week ahead BBC at 955 had max of 34 Fri and my phone app say 33 for Heathrow now Fri and down to 28 by Sat and cooler Sunday

iphone app for Heathrow has 30C+ for the next six days: 30, 36, 33, 31, 32, 32, then 29 on Wednesday. 

Met Office has 29, 37, 35, 33, 33, 33.

A long hot spell by any measure. 

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Heathrow still showing 37C this morning on the automated output.

However, the text forecast goes against it - which seems unusual and presumably rules out human "tweaking" to the automated forecast?

"Another mainly dry day with some long sunny spells, although an isolated shower is possible later in the day. Very hot inland, but onshore breezes keeping coastal areas cooler. Maximum temperature 35 °C."

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Heathrow still showing 37C this morning on the automated output.

However, the text forecast goes against it - which seems unusual and presumably rules out human "tweaking" to the automated forecast?

"Another mainly dry day with some long sunny spells, although an isolated shower is possible later in the day. Very hot inland, but onshore breezes keeping coastal areas cooler. Maximum temperature 35 °C."

Looks like they have tweaked it to 36C now. 

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Arome is now in range and is showing 37C in the west of London.

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Looks like they have tweaked it to 36C now. 

I doubt there's much tweaking going on at this time of day... I'd suggest it's more likely the newer UKV run came out in the meantime.

(IIRC they're run every 3 hours, hence the relatively common bobbing up and down of temperature forecasts during the day).

EDIT: Here we go:

https://www.metoffice.gov.uk/research/approach/modelling-systems/unified-model/weather-forecasting

UKV:

- run hourly out to 12 hours (unless shown below).

- run at 00z, 06z, 09z, 12z, 18z, 21z to 54 hours.

- run at 03z and 15z out to 120 hours.

 I suspect the 03z run was what changed the forecast... I'm guessing it takes a little while for them to update. All eyes on the 06z update!

 

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I doubt there's much tweaking going on at this time of day... I'd suggest it's more likely the newer UKV run came out in the meantime.

(IIRC they're run every 3 hours, hence the relatively common bobbing up and down of temperature forecasts during the day).

EDIT: Here we go:

https://www.metoffice.gov.uk/research/approach/modelling-systems/unified-model/weather-forecasting

UKV:

- run hourly out to 12 hours (unless shown below).

- run at 00z, 06z, 09z, 12z, 18z, 21z to 54 hours.

- run at 03z and 15z out to 120 hours.

 I suspect the 03z run was what changed the forecast... I'm guessing it takes a little while for them to update. All eyes on the 06z update!

 

Thats real useful info Darren. Thanks. 

Most sites starting the crystallise around the 36C—37C now. Astonishing really. We could still get the FOURTH hottest day ever recorded.

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There seem to have been some subtle changes in the model output to delay/moderate the start of the heat but make it last longer. Arpege now goes for 35C max tomorrow (actually checking the TWO charts there is still one solitary 36C gridpoint), but it is now up to 35C for both Saturday and Sunday.

Overnight lows look pretty remarkable with 21C or 22C possible along the south coast.

 

GFS goes two degrees higher on Saturday than on Friday:

Fri 33, Sat 35, Sun 33, Mon 34, Tue 33, Wed 32.

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Horrific stuff. My fridge is already giving trouble and perhaps will pack up due to this

Lots of drunk fools will be out on the streets as well

 

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MetOffice have just tweeted and they are going for 37C tomorrow.

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Arpege ensembles imply a ~50% chance of >35C on Friday

20% chance of >35C on Saturday

5% chance of >35C on Sunday

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My gut is that we are all going to be dissapointed on Friday.

That what happened last week was wierd, and exceptional. And this will turn out to be a normal heatwave as the uppers imply.

 

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My gut is that we are all going to be dissapointed on Friday.

That what happened last week was wierd, and exceptional. And this will turn out to be a normal heatwave as the uppers imply.

 

Yes, mid 30s for potentially 5 days is a normal heatwave. . . 😂😂

Yes, mid 30s for potentially 5 days is a normal heatwave. . . 😂😂

May be wrong but I doubt we will see mid 30s for 5 days. Certainly Friday but I doubt we will get close to the record like we did last week.

Tbh though it kinda feels like mid 30s is the new normal, I can't remember the last time we didn't see mid 30s at least once per summer.

 

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