Winds of up to 60mph could hit parts of West Sussex tonight, the Met Office warns.
It has put in place a yellow rain warning for much of the county with the expectation of showers and thunderstorms.
A spokesperson for West Sussex County Council said: “There is some uncertainty as to the exact locations which are likely to see the greatest rain totals although southern areas currently expected to be at the greatest risk.
“This band could be locally very heavy and accompanied by strong, gusty winds and rain could give 30mm in three hours.
“There is also the potential of isolated gusts to 60 mph along the south coast which could lead to falling debris especially leaves and branches.”