Forecasters have warned that more than an inch of rain could fall in just one hour in parts of England and Wales as thunderstorms strike
Londoners' preparations for their bank holiday may be derailed by heavy rain and thunderstorms, as the city is predicted to see heavy downpours on Sunday afternoon.
When thunderstorms strike, forecasters have warned that more than an inch of rain could fall in some areas of England and Wales in only one hour.
A fresh thunderstorm alert has been issued for the south west of England, including parts of north and west London, until 7pm on Sunday, warning that there could be flooding and travel disruption.
The Met Office has predicted heavy rains in the capital at around 5pm on Sunday and temperatures will be cooler than on Saturday, when the mercury reached 21C.
Travellers leaving the capital could be hit by worse conditions as slow-moving showers and thunderstorms are expected elsewhere in the country, with 20-30mm of rain due to hit.
The Met Office has issued a yellow warning from midday until 8pm across much of central and northern England and the north east of Wales.
Hail and lightning strikes may occur, with people warned to expect possible flooding, travel delays and power cuts.
Forecaster Kathryn Chalk said: "There could be some disruption, especially for people travelling or out trying to enjoy the bank holiday weekend.
"So I'd say definitely keep an eye out on that. Some southern areas of England may also see a few heavy downpours, perhaps even the odd rumble of thunder as well."
She added: "It's just a more unsettled weather regime where the air's unstable and with more heating in the land it helps develop a storm."
Saturday was dry and warm for many.
A mix of "sunshine and showers" will be the case for many on bank holiday Monday, with drier conditions possible in parts of Wales, Northern Ireland and south-west England in the afternoon.