Red warnings have been in place for millions in the southwest and southeast England and south Wales.
But across all the UK there are weather warnings in place. These are pictures showing the effects of Storm Eunice as it spreads across the country.
Storm Eunice hits UK - live updates
We'll be updating this all day - so make sure to check back again later for more pictures.
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Damage to the roof of the O2 Arena
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A fallen branch on a car in a car park in Lyme Regis, west Dorset
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A tree fell down, causing blockages on Egloshayle Road, Wadebridge in Cornwall Pic @WadebridgeCFRS
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A fallen tree in Bude, northeast Cornwall
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A Spire fell off in Somerset. Pic Matthew Hodson
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Damage to a car caused by falling bricks from a tower block in Hillingdon. Pic @cobbyqpr/Twitter
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Emergency services look at the damage to the roof of the O2 Arena
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The roof of a building that has blown onto the tracks at Banbury, Oxfordshire. Pic @NetworkRailCML/Twitter
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Road blocked in Tenby due to a fallen tree
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An Air Portugal jet was forced to abort its landing in Heathrow Airport
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One of the two lorries which have been blown on their sides in the high winds, closing the M4 in Margam, south Wales
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Fallen trees blocking lines in the Ewell West areas in Epsom
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Fallen tree blocking a road in Sudbury, Suffolk