Motorists and homeowners have been warned to take extra care as heavy rain batters Lancashire.
Thunderstorms and hail will move northwards across the county with up to 3cm in three hours in places.
Open areas could also experience gusty winds.
In Blackpool, a house caught fire in the roof space after being struck by lightning.
Firefighters were called to the house at Cornwall Avenue, North Shore, Blackpool at around 4am on Wednesday. A spokesman for the Fire Service said no-one was hurt.
The public were being advised to take extra care during Wednesday's rush hour.
Conditions were expected to improve by lunchtime, although the heavy rain will return on Thursday.
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