A yellow weather warning has been issued for thunderstorms in parts of south-west England and much of Wales, the Met Office said.
The warning is in place between 3pm and midnight, and the forecaster has warned of heavy rain, hail and spray which could affect drivers.
The warning also means there will likely be some damage to buildings from lightning strikes and delays to public transport services.
The Met Office said some localised flooding is possible as are short-term power cuts.
People should check if there area is at risk of flash flooding, and prepare a flood plan and emergency flood kit.
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The areas affected across the South West include Bath, North East Somerset, Bournemouth, Bristol, Cornwall, Devon and Dorset. Nearly all of Wales is affected.
Herefordshire, Shropshire and Worcestershire in the West Midlands, and Hampshire in the South East, are also affected.
It comes off the back of a record breaking heatwave this week.
The Met Office said on Tuesday that the record for the hottest May day has been provisionally broken when temperatures reached 35.1C (95F) in Kew Gardens.
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(c) Sky News 2026: Thunderstorms warning issued for parts of England and Wales
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