I think AROME could be right for this evening for the London area. Can see discrete signs of a cumulus field setting up just inland on the south coast. Very faint on the SAT though
Definitely bad for some people, but for others it’s been a cracking breakdown for the midlands, Wales, Scotland etc. I would have been stormless too if I hadn’t taken action and driven straight through the Thursday afternoon Surrey storm
If you’re talking about today it was because the low cloud lingered from the south midlands all the way down to the south coast pretty much so the sun could not get to work and no surface heating could occur to initiate any storms.
We’ve had plenty of 4 hour or longer storms in this country since the 80s! You only have to go back to last year’s July event. Then there have been events like that or better each year before. The weather setup just hasn’t been quite right this year for storms of those durations in the south especially. Been a bad year for French imports.