The Met Office has issued a severe weather warning for a large part of the south east, with Brighton and Hove at the centre of the affected area.
Up to an inch of rain is expected in a matter of hours which, forecasters said, could lead to surface water flooding and make driving conditions dangerous.
The warning was issued by the Met Office at just after midday today (Sunday 10 June) – just a few hours before the deluge began.
TV and radio weather bulletins suggested that people could be affected by the downpour even as it eases off as they drive to work in the rush hour tomorrow morning.