Flash flooding and lightning strikes could hammer parts of Norfolk this weekend.
The Met Office has issued a yellow weather warning for Sunday (June 18), covering much of England and Wales.
It follows a fortnight of hot and sunny weather which saw temperatures reach 28C.
The warning is in place from midday to midnight on Sunday, with some places potentially having 60mm to 80mm of rainfall in six hours.
The Met Office has also warned there is a chance that homes and businesses could be flooded quickly, while lightning strikes, hail or strong winds could cause damage.
Train and bus services are likely to be delayed and power cuts could occur.
The Met Office added that while there is a high likelihood that thunderstorms will develop, it remains uncertain where and when they will hit the region.
Norfolk is currently in the throes of a yellow heat warning issued by the UK Health and Security Agency (UKHSA) unit Monday (June 19).
Following the thunderstorms on Sunday, the forecast for next week appears unsettled, with light showers and sunny spells forecast while temperatures remain in the low 20s.
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