Thunderstorm warnings are in place for parts of southwest and southeast England, East Anglia, Wales and Northern Ireland, with some areas at risk of flooding, lightning strikes and hail.
The Met Office says up to two inches of rain could fall over a few hours in Cornwall, Devon, Dorset, Somerset and in western parts of Northern Ireland on Tuesday.
Two yellow weather warnings for thunderstorms are in force for southwest England and Northern Ireland until 9pm today.
The warning in Northern Ireland began at 8am, while the one covering much of southwest England started at noon.
Truro, Plymouth, Exeter, Taunton and Dorchester are also affected by the warning in England.
In Northern Ireland, Londonderry/Derry and Armagh are among the areas forecast to be hit by storms.
Met Eireann in Ireland has issued an orange thunderstorm warning – meaning there could be a threat to life and property from “infrequent and dangerous weather” – covering southeastern areas up until 8pm.
A yellow warning – of “potentially dangerous” conditions on a localised scale – is also in force across much of Ireland until 10pm.
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A separate new thunderstorm warning – which started at noon until midnight – covers parts of southeast England and East Anglia.
Portsmouth, Brighton, Reading, London, Canterbury, St Albans, Ipswich, Cambridge and Norwich are among the areas affected by the yellow weather warning.
The Met Office warns “sudden flooding” and lightning strikes could lead to travel disruption, with some train and bus services cancelled and road closures.
There is also a chance of power cuts to homes and businesses.
Meanwhile, a separate yellow weather warning for rain is in place for parts of the Midlands, North East, North West, Wales and Yorkshire and Humber overnight until 6am on Thursday morning.
Areas affected include Birmingham, Nottingham, Stoke-on-Trent, Manchester, Hull and Newcastle.
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Met Office forecaster Amy Bokotan said: “The downpours could be slow moving, and that’s the main trouble – the wind’s quite light at the moment so when they do form, they could be quite slow moving and intense.”
She added: “Where you see them they could be quite intense and dramatic, but not everywhere’s going to see them and some places just down the road could be completely fine and shower and thunderstorm-free.”
The warnings have been issued ahead of an area of low pressure approaching the UK from the east on Wednesday – which will bring heavy, prolonged rainfall.
William Turner is a seasoned U.K. correspondent with a deep understanding of domestic affairs. With a passion for British politics and culture, he provides insightful analysis and comprehensive coverage of events within the United Kingdom.
