A dozen flooding incidents across the district had to be dealt with by the fire brigade last night.
The fire service attended six calls in St Albans, including an electrical fire in Sandringham Crescent and a vehicle stuck in floodwater in Highfield Lane.
Other areas hit by the thunderstorm were Park Street, Dellfield Street, Tavistock Avenue and Oakfield Road.
All the incidents were logged as single properties affected by water damage.
Fire crews were also called out six times to Harpenden, where the High Street, Roundwood Park, West Common Way, Hillside Road, Leyton Road and Luton Road were flooded.
Homes and businesses in each of the roads sustained damage in what turned out to be an exceptionally busy night for the emergency services.
Herts County Council spokesman Simon Hoggett said across the county, the fire service had received more than 150 calls for help throughout the storm.
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