The Met Office has issued a warning of rain for south west Hertfordshire until midnight tonight, warning the public of disruption to travel and localised surface water flooding.
A spokesperson at the Met Office said further heavy showers and thunderstorms with hail and gusty winds will affect southern parts of England during the rest of today and 5-10 mm of rain could fall within an hour.
The Met Office said: "The public should be aware of the risk of disruption, particularly to travel, with the possibility of localised surface water flooding, hail temporarily covering roads and also damage from lightning strikes."
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