Central southern England is the worst place for storms, everything goes either side of here, west or east of here

Not expecting anything as usual

looks like normal summer weather for once. Thank god for that.

The oven for last 2 months has been horrific here

Both showing high pressure to the SW/S. 

GFS has (on this run at least) almost dropped the 'troughing gets very far south to cover all the UK' idea (shows it happening briefly on Sun 27th before the high blows it away) and actually has the high pressure centred over the UK by the end of the week.

AIFS toyed with the same troughing idea in the 18z, but has reverted to its previous position of keeping the high centred not far away to the SW (but at the end of the run the high has pulled away into the mid-Atlantic with a big low centred over Denmark/southern Scandinavia, introducing a pretty bracing northerly (850's widely 2-4c over the UK - all very FI, though)

Temps on both nothing remarkable (20-25c maxes, probably)

Still all in the nether reaches of the runs (although Sat 26th now starts at t+192), so just trend-monitoring at this stage. I've seen worse, though!

hard to tell which model is most accurate, but you could be in the sweet spot or perhaps west of london. but impossible to say until the event itself unfolds

Have you forgotten the great flood of July 20 2007? 

I know it off topic, but maybe the breakout thread might be better as a sticky in the model output discussion? Easier to find and the most visited discussion area? 

I'd agree

Yes potentially looking very wet this weekend, and then next week might not get above 25c even in the SE. 

Possibly, but the 6z GFS seems to following the trend of the last few days and settling things down quite nicely after a couple of days of useful rain.

Certainly no heatwave looking imminent with the high pressure staying slightly to the west, bringing winds from a northwesterly sector, but temps slightly above average, it will be bright, largely dry, and warm (but a fresh warmth rather than humid). Peak summer weather if you ask me (if it's on the money).

Met Office have upgraded to Amber for the S.E but downsizes the at risk area considerably. 

The yellow risk area hasn’t changed, they’ve just added the amber warning area now that the model output is coalescing around the area of most intense rainfall.

The 06z ICON has 25-75mm, 06z UKMO 50-60mm.  The high res (4km) ALARO only covers the eastern side (west of London eastwards) but shows 20-30mm in the narrow area of intense rain. AROME (2.5km) widely 20-40mm through the zone of heavier rainfall, and as much as 70mm in a few spots.

In my experience, models more often than not overplay rainfall amounts from thunderstorms, yet underplay when big showers dump a huge amount. 

I think this is an astute analysis. Element of wish casting on my part as I’m biking next week. But looks generally decent from late Tuesday onwards.

25c would be above average for much/all of the SE. 

I think that’s mainly an issue around resolution and the difficulty of getting the exact location of the pockets of intense precipitation right.

To be honest I’m amazed, given the physics involved, that they get it as close as they do at high res.

I noticed that amber warning addition but overall decreased risk elsewhere.  There is another warning for SW England for (Devon and Cornwall) for Monday. The bits in between, that's you and me, might get some rain early Sunday morning. The BBC automated weather warnings that were there for Central Southern England and in the forecast that covers me, have gone. It's as usual, a tricky one to forecast even at this short notice. 

GFS 6z starts to build pressure back from the SW/S next week, but then reverts to its 'troughing getting far south to cover the whole UK' by a weeks Saturday. Then it's a battle between the high to the SW and low. The low keeps the upper hand, although high pressure does keep a foothold along the south coast.

AIFS still bullish about building the high pressure over all/most of the UK through next week and well into the week after, although it also keeps the notion of troughing to the east expanding westwards late in the run to first introduce a cool northerly, then unsettled to the eastern counties.

Nothing decided yet. AIFS has been good, but GFS keeps coming back to its low pressure theme.

Since this will be a plume of very warm, humid air interacting with a surface and upper trough I think your thunderstorm deficit has a decent chance of ending tomorrow.

I can only go on what was on the Met O automated forecast which up until today had my area just in the yellow Warning . No Warning there now🤔

As expected central southern England,  storm and rain  risk virtually eliminated,.

Strange how one can look at the same charts and see different things (especially Saturday)

https://weather.metoffice.gov.uk/warnings-and-advice/uk-warnings 

There's considerable variation between the models even at this short range regarding tonight's rain, the extent and amounts thereof. 

The 12z ICON-D2, for example, runs the heaviest rain towards the west, and the 15z (which is rolling out) dials the amount back a fair bit and moves things further west still, at least in the early hours. Here's the 12z and then the 15z for the same time, accumulated by 4 AM BST tomorrow morning:

https://images.meteociel.fr/im/65/13710/icond2_25_15_0ntz5.png 

https://images.meteociel.fr/im/21/20523/icond2_25_12_0gna4.png 

The 12z ended up like this (as of midnight BST on Sunday):

https://images.meteociel.fr/im/93/5540/icond2_25_35_0yap4.png 

Contrast that with the AROME 12z, which has the core of the rain further east (at least in the south!)

https://images.meteociel.fr/im/14/6406/arome_25_35_0whg1.png 

Even the MetO raw output hasn't been immune, offering 13 hours in a row of heavy rain IMBY in the morning output (hence the amber warning), compared to 5 hours in a row on the latest (presumably from a 12z run of whatever ensemble suite they use these days). 

I've a feeling here at least it's going to be one of those events where there's either a piddling amount (just a few mm) or a deluge of 20mm or more (if things move further east again, as sometimes happens). There will be similar situations on the western side of that band of rain, too - the difference between next to nothing and flash flooding is a very fine line it seems!

GFS 12z moving towards the AIFS solution 

AIFS sticks to it's guns

AIFS has this nailed IMO 😃

Would be like a 'traditional' summer spell, with the AH ridging in from the SW, clearer Atlantic air, and temps low- to mid-20's.