Torrential rain and thunderstorms are lashing the UK – with parts of southern England enduring more rain in nine hours than the average for the whole of August.
The Met Office has issued 13 flood alerts – eight in southern and central England and five in Scotland – as the downpours are expected to continue into Friday.
One of the worst-affected areas on Thursday was Eastbourne, where 60mm of rainfall was reported by the afternoon.
At one point, the town’s shopping centre had to be evacuated after drains on the roof began to overflow, but it later reopened.
In nearby Hailsham, three fire crews were needed to extinguish a blaze after a house was struck by lightning.
Elsewhere, several residents in Brighton posted pictures of substantial surface flooding on social media – with others uploading videos of water seeping through doorways.
Madelaine Hunter recorded water flowing heavily down a residential street, submerging the wheels of some cars.
There were also problems reported on the railways – with Southern services between Lewes and Wivelsfield temporarily suspended while a blockage was cleared from the line.
Although the line reopened, significant delays and some cancellations remain.
RAC spokesman Pete Williams said: “Drivers are likely to get a taste of some tough driving conditions over the next 24 to 48 hours with the forecast of torrential rain and the risk of hailstones.
“Exercising care and caution is vital in heavy rain conditions, especially as traffic volumes are particularly high at the moment.
“Cut your speed, use dipped headlights and avoid driving through deep water if you encounter flood conditions and remember to show consideration for other road users, particularly cyclists and pedestrians.
“Also be prepared to pull over and wait for the worst conditions to subside if you are hit by a heavy storm.”
While the rain will also spoil Friday for many, there is better news on the way.
Nick Prebble, from Meteo Group, said: “Once the rain has cleared on Friday much more settled conditions are to be expected through the weekend and into the early part of next week.
“Whilst temperatures won’t be overly impressive, there will be some sunshine around and it will be a considerable improvement to the current wet weather.”