About 2,000 homes and businesses have lost power and some flood defences have failed as Storm Callum batters the UK.
Some coastal flood defences in Exmouth, Devon, have been breached and a yellow weather warning is in place for the west coast and north-east of England, parts of Wales and Northern Ireland.
Wind speeds recorded in the Scilly Isles hit 76mph and 64mph at RNAS Culdrose in Cornwall.
In Northern Ireland, power has been lost to 500 properties.
The weather has caused the cancellation of a number of flights in Exeter, Bristol, Belfast City, the Isle of Man and Cardiff.
Western Power Distribution said about 1,080 properties were without electricity in Cornwall, while Electricity North West said 419 customers in Cumbria and Lancashire were affected.
Rail passengers travelling to and from south-west England faced cancellations and delays of more than two and a half hours after power cables fell on to the track between Totnes and Plymouth.
The line has since re-opened but Cross Country Trains has cancelled all further services through the area.
A spokesperson for Great Western Railway said that it was still operating and every effort would be made to get people home.
A coach full of children had a narrow escape when a tree fell into the path of their school bus near St Agnes in Cornwall.
The driver, Alan Nielson, said it came down 10-15 seconds before they pulled on to the road.
Several vehicles have been damaged by falling trees in the Biddulph area of Staffordshire. Trees have also blocked roads near Audley in Staffordshire and Nantwich in Cheshire, police said.
Cormac, an engineering and construction contractor for Cornwall Council, said it had dealt with reports of 30 fallen trees and about 25 flooding cases in the past 12 hours.
The emergency services and authorities have urged people to avoid taking unnecessary risks after a man was spotted swimming with seals in Dawlish, Devon.
Another swimmer, Ross Edgley, who is attempting to complete a 2,000 mile swim around Britain, is floating on a boat in Grimsby, Lincolnshire, waiting for the North Sea to calm down enough for him to continue.
The 32-year-old is not allowed to step foot on land under the rules of the challenge.
The Environment Agency submitted plans earlier this month to improve the flood defences in Exmouth.
If approved the £12m works will help protect the currently flooded esplanade and highway by stopping the flow of water from nearby roads.
Storm Callum is the third named storm this year after Storm Ali and Storm Bronagh last month.
In Wales, the worst of the rain is expected to hit south-facing hills with up to 200mm falling in a 36-hour period, according to the Met Office.
A yellow warning for the country is likely to cause problems on the roads, rail and ferries, while motorists have been warned to be prepared for poor driving conditions.
In Northern Ireland a yellow warning has been issued for strong winds.
Callum not adhering to the speed limit on Strand Road in Sandymount... #StormCallum #Dublin #Hightide #StaySafe @deric_tv @rtenews @LovinDublin @JOEdotie @StormHour @MetAlertIreland pic.twitter.com/gW4gnxR07Z— David Costello (@DavidCostelloDC) October 12, 2018
The Met Office said heavy rain was likely to move northwards across England throughout the day with heavy bands of rain affecting Lancashire, the Pennines and Cumbria.
Gales were also forecast for Cornwall and Bournemouth and may continue until 18:00 BST on Saturday.
In Scotland strong winds and rain were forecast for Lanarkshire as well as the Outer Hebrides, much of north-west Scotland, Orkney and the Shetland Isles.
Making plans for this afternoon? Windy for all, with plenty of rain spreading northwards across the country. However, remaining fine with sunny spells in the southeast pic.twitter.com/Kq93qVHikB— Met Office (@metoffice) October 12, 2018
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