The Met Office issued an amber weather warning for London and much of southern England on Wednesday night as torrential rain threatens to cause localised flooding.
Downpours have already caused difficult conditions in southwest England, which remains under a yellow warning.
Forecasters put out a further alert for the capital and parts of the southeast and east of England.
“Very heavy rain is expected to cause surface water flooding overnight,” it said.
An amber alert means homes and businesses “are likely to be flooded” and there will be disruption to public transport and roads will be affected by spray and flooding.
It comes only a fortnight after similar downpours caused days of disruption on the London Underground and left some shops and homes underwater.
BBC weather forecaster Ben Rich tweeted: “Driving from Devon to London tonight, and I can confirm road conditions are NOT GOOD.
“Met Office amber warning for rain is entirely justified - take care if you’re heading out. Flooding is very likely too.”
Driving from Devon to London tonight, and I can confirm road conditions are NOT GOOD. Met Office amber warning ⚠️ for rain is entirely justified - take care if you’re heading out. Flooding is very likely too. pic.twitter.com/Kls3iAzxNL
— Ben Rich (@ben_rich) October 20, 2021
— Tomasz Schafernaker (@Schafernaker) October 20, 2021