The April showers are set to continue this week as rain and hail is predicted across the country - with no end in sight to the hosepipe ban.
Rain will spread North East across England and Wales as thunderstorms and high winds hit Northern Ireland and Scotland.
Up to 40mm of rain is predicted, prompting warnings from the Environment Agency of surface flooding and poor driving conditions in the South East, South West, Wales, and West Midlands.
A spokesman said the heavy and persistent rain could lead to localised surface water flooding in southern England and south Wales.
He added: "We are keeping the situation under constant review and will update the flood guidance if necessary."
Hail and heavy downpours are predicted on Thursday, with more to follow on Friday.
Night-time temperatures are expected to dip to around 1C.
Sally-Jean Webb, meteorologist at MeteoGroup UK, the weather division of the Press Association, said: "It will be a very wet and windy day as an area of pressure from the South West comes up the Irish Sea overnight."
She added that the frontal system will move North East and will arrive in the south of Scotland later.
"This will accompany really strong winds, especially in North Wales and the South West. These conditions will continue through into Thursday for Northern Ireland and Scotland, though England and Wales will see some sunny spells interspersed with heavy showers."