Heavy rains this morning could lead to localised flooding in parts of London, the southeast and the east, according to the Met Office.
The forecasting service issued a severe weather warning for areas from Kent up into Hertfordshire and Cambridgeshire, warning that parts of the country could see as much as 10mm of rain in an hour.
The severe weather warning follows bursts of heavy rain in parts of the southeast and east of England, with fallen Autumn leaves impeding drainage.
Rain in the southeast is expected to clear away by mid-afternoon, moving northwards up to Yorkshire as the day goes on and into southern Scotland by about 6pm.
Things started off drier in the west, with fog and low cloud expected to clear leaving a sunnier day with some scattered showers.
Rain that moves into the north over the course of the day will clear northeastwards overnight, leaving clearer skies for a while.
But strong winds and more wet weather are expected on Thursday. Wednesday’s severe weather warning is valid until 11am.