Weather warnings have been issued for parts of the UK as a French storm moves in.
An amber warning covers parts of the South East and London, with the Met Office forecasting “very heavy rain” overnight.
This is in effect until 2am on Thursday and could also bring transport disruption, difficult driving conditions, power cuts, and likely flooding of homes and businesses.
A yellow rain warning covers a larger part of southern England overnight and until 3am on Thursday.
Wet and windy weather is likely to bring “some disruption” to the region, forecasters said.
Met Office forecaster Becky Mitchell told the PA news agency: “We’ve got yellow rain warnings in place which will last for the rest of Wednesday until 3am on Thursday, covering the southern counties and the Channel Islands.
“Heavy and persistent rainfall will fall in the areas covered by the warning, mostly between 15-25mm, but some places will see potentially 30mm or higher along with some rumblings of thunder.
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“There’s also likely to be very strong winds, typically around 45mph on the coasts, reaching 70mph in the Channel Islands.
“This may cause some disruption to commuters tomorrow morning, as some places will see some flooding – while the impact of thunder could cause power cuts.”
The worst of the storm is expected to hit northern France, and the Channel Islands, being close to France, are also expected to feel the effects.
The rest of the UK is unlikely to experience the storm.
Instead they will notice the weather turn much colder, with parts of Scotland dropping below 0C as a cold front moves in from the north.
The unsettled weather is likely to continue throughout the week, with persistent rain over the weekend.
The heaviest rain is forecast for western Scotland, with up to 60mmm expected to fall in 24 hours.
Northern Ireland, northern England and Wales, could see up to 20mm of rain could fall over six hours, while the rain will be lighter in southern and central areas.