chapmanslade

At least initially there is going to be a significant lack of moisture. Dew points sub zero over France will not be conducive to any convection for most of next week. It isn't until after next weekend that we see any significant moisture.

Completely agree. This is not a one run wonder and has been there in one form or another for the last 3 or 4 days, just like the last hot spell in June. Yes the extent of the plume and the level of het vary from run to run but the basic setup is always there.

To be fair France is far from bone dry. There has been a lot of rain there for the last couple of weeks. However the last heat spike there about 3 weeks ago was well picked up by the models (and ignored by some on here) from a good 10 days out. Since then there has been little to write home about with France being notably cool and wet, but once again a significant heat event is looking more and more likely. Sadly I will be in France around then and I can assure you 40C+ makes work very troublesome! I think the models have been pretty good of late, unfortunately many on here get hung up on fine detail rather than looking at trends at 10 days out. There was somebody on here who modified the charts a while back to blur out the resolution with time which has always seemed a good idea to me where trends and broad patterns rather than detail are important

At no stage is the GFS an outlier on that graph!

It is probably actually just the lack of wind I suspect - just makes it feel more humid. Methinks 27C is not really hot, should try 40C plus last week in France, that was hot!

Not really towers - more thick pancakes

Nah - you need a good 40C to get things going I don't think the tree enjoyed it either!

Here is a video from our side of that storm. We are to the west of Limoge and the storm was in between. We just had grumbling thunder from it. The storm developed from nothing to this in just over 2 hours. VID-20220619-WA0020.mp4

Here is a video of the sort of CG's we had to endure. After 20 or more of these you wonder what is going to come next. Apologies for my son's language, but he probably had the assessment about right. Remember it was dead still (no wind or rain) and one of these every 20 or 30 seconds. VID-20220619-WA0001.mp4

It was still 31C at midnight! We ended up with about 3 hours of elevated storms from about 23.30 and then a really nasty 'tail end Charlie' dry cell about 4am. Clearly more surface based with a huge amount of shotgun thunder. In the region of 20 CG's within a mile, and a couple at less than 300m. Would have been nice to see the cloud structure but it was just far to dangerous to go outside. Only low 30's today but still in an Estofex level 2 for later on.

There is indeed plenty of heat here. Currently 40.3C here in the Charente. Minimum last night was 23C, similar tonight.

Have to say that is not the best drawn diagram! Sitting in the level 1 in SW France here - will be glad to see the back of this heat - peaking today at 42C and it is just impossible to work in this without an AC cocoon. The difference between 30C and 40C is huge.

Plenty of heat here today. Just popped above 40C! I'm in France by the way!

You had three on the trot last week!

Indeed. Some would make you think we WERE in October already. Plenty of 20C plus days in the last 2 weeks here, currently 21.6C with every suggestion that the ex TS Alex will scoot up towards Iceland on Friday leaving us to pull in the very warm air off the continent. OK it will be warmest in the south but that is ALWAYS the case in most summers. Mid 20's entirely possible, but from that source there will always be the risk of thundery downpours. We are having an entirely average spell of UK summer weather, not dross, not scorching, just average.

But the GFS 06z showed 29c for London next Monday. One run to another at a week away. What is perhaps more pertinent is that there is very likely to be significant heat in France next weekend and there is a considerable chance that may spill north to the UK, with or without storms. It is far from 'utter dross' as you posted earlier, it is actually fascinating with all manor of potential outcomes.

Yes, increasing number of really very hot possibilities starting to show up mid month. Control and Op on the GFS 06Z appear at odds with the ensembles, but for Paris they have a lot more support. All as a result of the troughing staying out slightly further west of the UK.

You are about 5 minutes away from a torrential downpour

Talk about glass half empty .... Lost the glass altogether now. 30 miles north of you we are likely to get to 20C on Tuesday and then close or above pretty much from then on this week. We had 5 days at or above 20c this last week, including late on yesterday. Whilst not high pressure dominated the sun is so strong at this time of year it is easy to get to 20c even late in the day as we did yesterday.

This is exactly as you say forming on the convergence zone. It is also developing quite quickly. Very close to the sun breaking through here, visible disc from time to time.

They are completely unrelated to the later synoptics. Current storms are on the leading edge of the warm front / plume. Tonight's storms will initiate over the Channel / Southern UK as a result of destabilisation of the plume and are not related to surface heating

I don't doubt that at some point on Sunday some people will see some heavy rain, but many will not. Look at what ECM thinks for Sunday, many parts with plenty of warmth.

I think some are completely missing the point about this weekend. It is NOT going to be a damp, cold, wet, grey day! Events are being driven by a considerable convective event over France this weekend and what happens there will largely determine the weather we get as it spills north. Left over MCS, maybe. Convective weather, very likely. Models are not yet clear on how far this convective plume will spread north, which means uncertainty on the local weather, and it will be local with some places in the low 20's in the south and some much depressed in heavy outbursts of rain. In fact this very event is being discussed in the convective thread!

Looks more like Asperitas cloud to me

Exactly. You only have to look at the day 10 ECM (hot air over southern UK) and day 10 GFS (hot air stuck over Spain) at the moment to see how small changes make big differences to the weather we get. If the heat is 100 miles south of the UK it takes very little to get to us compared to coming from Spain. I always assume about 500 miles per day for airmass movement, so if the heat is over Spain it takes about 3 days to reach the UK with a southerly, if it is over France it takes a day. Getting a south wind for 3 days is a lot harder than for 1 day. A dry airmass with lots of cloud ???