P17 is quite frankly bonkers. 850s nearing +25C

AIFS again not interested in carrying on the heat . Can't see it being wrong.

UkMet has a scorching 38c for the London area on Monday. Bonkers stuff.

And at the same time the temperature doesn’t reach the teens (°C) in parts of the NW of Scotland.

GFS Op 00z: HP moving up from the SW and settling itself over the N Sea Mon 30th to pump up hot air from the Continent, as in the last hot spell this year. This followed by a brief return of the W-lies, so cooler until Fri 4th when the ridge again advances, this time more towards Scotland, with some overspill of hot air from the Continent into the S (but less directly) Mon 7th. This hot air comes with built-in LP which interacts with a trough to the north; by Fri 11th that takes over and LP 1000mb Fair Isle is directing N/NW-ly winds across Britain.

ECM: differs from GFS from Wed 2nd when the HP from the SW puts in an earlier appearance, and more to the south, so by Fri 4th it is 1025mb over England with less of a hot feed from the Continent. The model continues to differ as pressure drops, 1010mb Channel Sun 6th with weak NE-lies for N Scotland.

GEM; places next week's HP even further south than ECM and by Fri 4th there are SW-ly gales for N England and Scotland, with steady W-lies thereafter and no sign of anything from the NE

GEFS: for the S, an agreed peak 11-12C above norm for Mon 30th (esp SE, less in SW), but back to norm Wed 3rd and staying there of a little above to Sat 12th (though op run persists in predicting a second heat wave Mon 8th, it's not well supported) Very little rain at any time. For the N, temps oscillate with again a peak Mon 30th, but only 5C above norm, and the drop in temp following brings a cool spell with temps below norm to Sun 7th, after which mean near norm but in a moderate spread of ens members, it's the op & control suggesting something warmer. Small amounts of rain at any time, most persistent in W.

AIFS; London temps increasing to max 32C Mon 30th, dropping to only 16C Thu 3rd with rain then and preceding day; daytime maxima then settle around 20C but again cooler with rain Thu 10th (It's Wimbledon fortnight!). Edinburgh temps reach max of 24C Mon 30th and then follow the London pattern but mid-teens rather than 20s. Small amounts of rain at any time except for a day or two around the 30th.

I shall be away on holiday for the next week; expect reviews to begin again Sun 6th. If anyone wants to take over for the week, please feel welcome.

Where are you seeing 38C? Ours is showing 33C and I'm not aware of any problems.

What is the reason for the lack of storms over land in recent years? I thought with increased energy they would increase. Also all of the storms coming up from France, despite what the forecasters predict. run East over the sea in preference to  developing any convection over the land.....  It seems odd.

I'm 99% certain that it was on the regional version of the UKMet UKv (on the TWO model viewer) when I posted earlier but that's currently displaying Wednesday's 3z at the moment for me 🤣 so I'm not sure whether it's a glitch my end, my eyesight early in the morning or something else! 

Thursday's 03Z is now available. Updates were delayed this morning because I switched to the new Met Office API. I can see 37C on Monday in the London area, so it's possible there is a 38C somewhere. 

Ahh that explains it - and yes it's the 108hr chart for the South East which shows a couple of 38c in the West of London. 

As an aside can I just add that the upgraded paid version of TWO is fantastic - I'm definitely signing up to it when my current (awesome prize) subscription runs out.

Extraordinary heat coming up for central UK however what are the models suggesting for the middle of July? Reload of heat interspersed with cooler temperatures ? Or possibly a cool down and staying that way for the foreseeable future? 

Here, east of the Pennines, weather fronts are losing their oomph by the time they do reach here, so further south and east I don't expect much relief in terms of significant rainfall. We're just getting a few light showers in the wind, then the sunshine comes back once the decaying front clears east. Trace amounts and not surprising when these fronts are running into higher pressure further south.

In terms of heat, I daresay this next heatwave, which officially it will be with Sat-Mon looking likely to breach the threshold for many central and eastern areas, could well repeat itself further into July, even if ensembles don't seem too keen. I don't think the current heat spike was nearly as pronounced going back 7-10 days in the output archives. Sometimes they just creep up on us, especially when there isn't a strong signal for a UK high and it's more transient in nature. The differences become micro in scale, in the same way we lose out on thundery outbreaks sometimes by barely 50 miles! I'm keen on 7-9 July for potential heat and I'll be interested to see if the 850s around that time spike up a little more as we get nearer. Speculative, mind you, but I wouldn't be surprised.

After all, it really isn't taking much at all for us to tap into the significant continental heat, literally just a kink in the jet running more S>N with a low a little hesitant out to the west and suddenly we're looking at 33-35C in a few days time, potentially quite widely, too. Given the lack of certainty in the mid-term, it would be foolish to rule out further hot spells deeper into July, especially the further south and east you are (where, let's face it, the heat hasn't really gone from!).

It does at the moment look like an unsettled spell after a few decent days after the heat. So maybe starting around 6th July.  AIFS has been very consistent with this. Latest GFS 6z also now agreeing. How unsettled and how long it lasts unknown. 

Yes the difference in modelled maxima for the London area between the 6Z and the 0Z for the 7th/8th July is almost 20C.

More runs needed... 🙂

Indeed. Its crazy. Literally zero trend, and impossible (as always) to know what's coming up.

As a long time member and poster surely you must know that is where the ensembles come in. The GEFS and ECM ENS have been reasonably consistent in recent times. The trend is quite obvious:

1) Becoming very warm or hot, at least in the southern half of the UK

2) A cool down next week 

3) A weak signal (GEFS seems keener than ECM ENS at the moment) for higher temperatures and possibly another very warm or hot spell during the second week of July

Indeed, and from what I can see as well the 06z operational was a considerable outlier anyway. There remains little point when the outlook is so uncertain in FI to take notice of any operational in isolation.

Looking through the GEFS there are some quite extreme runs in both directions. It seems like the jet is modelled to be quite amplified around the second week of July, and depending where it sets up it could either bring the 0C isotherm or the 20C isotherm across the heart of England!

Indeed. When I looked at the stamps in-depth earlier this week a number of them were building high pressure to the north and west of the UK, so an amplified pattern as you suggest.

As scillydave said earlier, the UKV does indeed show 38°C in London on Monday.

Yes absolutely, hence why I said it may be an outlier.

Definitely ensemble are key in this...individual runs are throwing up all sorts of extreme possibilities, both hot and cold.

However the uncertainty seems bigger later in July - the op run was very much at the bottom of the pack but not a total outlier, and did have some support. Equally there are plenty of hot runs going 15C+ at 850mb.

On the London grid point there are 3 runs going over 20C 850hPa during the second week of July..