https://www.wetterzentrale.de/en/topkarten.php?map=20&model=gfs&var=17&run=6&time=177&lid=OP&h=0&mv=0&tr=3#mapref 

Absolutely vile weather TBH. A min of 23 followed by a high of 37 even here...

I really hope that doesn't come off. Thankfully as it's a week away there's still plenty of time for it to change!

Don't look at the Control Darren. 

From next Monday 38c, 38c, 40c, 40c.

Sounds more like it's out of control! I have to admit a certain feeling of trepidation when the G(E)FS goes off on one - we all remember 2022, of course...

It does have 2022 vibes definitely.  But still plenty of scenarios possible most much cooler. My bet atm would be 34/35c for a day or two. But a fairly prolonged high 20s period for the SE. 

This chart is simply bonkers... note these are 850s!

https://images.meteociel.fr/im/41/243/gens_0_0_312alk9.png 

Indeed it has 850s above 21c for a week (21st to 28th). Top end of the ensembles as you would expect. 

The Control in the 6z is loopy. 5 days of 35+ forecast here, with a string of Thames Valley 40s on one day.

Thought for a minute I had a 38 there, but upon looking more closely it's 'only' a 36. 

But that would still put this area into July 2022 territory.

I see nobody has yet stuck their head above the parapet and started a 'Late June Heatwave' thread yet.

Perhaps you should do it in order to scupper it 🙂

I remember August 2003, being impressed with one day of the same (and a small zone of 576dam, which we exceed also in this model).

Another record casually broken were it to come off - the 12z GFS brings 576dam thicknesses over Kent at T+150, well in excess of anything previously recorded in June:

https://max.nwstatic.co.uk/gfsimages/gfs.20260615/12/150/hgt500-1000.png 

https://web.archive.org/web/20030310024855/http://www.booty.demon.co.uk/tthkxtrm.htm 

I remember 25 years ago when everyone got exited about the 564 line... how times change!

Looks like 578dam. Insane. 

Hadn't realised there were thickness charts on TWO for GFS - handy! 👍And yes, 578 in June is utterly bonkers. That's my word of the extended summer this year, I think!

Many years ago, around the turn of the millennium, a younger me asked on usw whether it was physically possible to get the 582 line over the UK (being the next step up from 564 - the old WZ charts went 474, 492, 510, 528, 546, 564, 582, and that was chosen based on the even older hand-drawn charts). The replies came in that we couldn't get anywhere near it, I think people found it mildly amusing that anyone should ask! Yet here we are, getting perilously close to seeing it. I suspect we *will* see it in the next 25 years, the way we're going, and I also suspect we'll never see the 492 line again in any of our lifetimes, or maybe even sub-500 (according to that thickness link from booty that I posted, the record low is 491 near Shetland. I know it was darned close to 492 here in 1987 too).

Yes, it has a straighter upstream jet and introduces a northerly feed by Monday, albeit an anticyclonic northerly - it's maritime air. It's joined in that by the new GEM, though ECM shows 20C+ 850s over the far SE still on Monday.