Heavy rain and strong winds are hitting the UK as Storm Aiden sweeps in from the west, bringing risks of flooding.
The Met Office says all of the UK will get wet and windy weather thanks to the storm on Saturday and the tail edge of a hurricane on Sunday.
Yellow weather warnings for rain are in place for Ireland and the west coast of England, Scotland and Wales, with wind warnings in some areas.
There could be power cuts and travel disruption in those areas.
Yellow weather warnings for rain are in place until 19:00 GMT on Saturday for Ireland and the west coast of England, Scotland and Wales, where travel disruption and potential power cuts are expected.
There is also a yellow warning for wind in place in Northern Ireland and western parts of Wales, Scotland and England.
The bad weather could last much of the weekend, and people have been urged to pay attention to the weather forecast as well as flood alerts and warnings in their area.
Martin Young, deputy chief meteorologist at the Met Office, said: "As the heavy rain and strong winds from Storm Aiden sweeps eastwards on Saturday, another system quickly follows on Sunday that contains the remnants of ex-Hurricane Zeta, bringing further heavy rain and strong winds.
"Given that this is falling on already saturated ground from what has been a wet October, there is an increased risk of flooding in some warnings areas."
Another yellow warning for rain covering Wales and north-west England is in force from 18:00 GMT on Sunday to 06:00 on Monday, and some communities could be cut off by fast flowing and deep floodwater.
Hilly areas could see 40-60mm (1.6-2.4 inches) of rain on Saturday, with 20mm-40mm ( 0.8-1.6 inches) in lower-lying areas.
Gary White, the duty tactical manager for Natural Resources Wales, said flooding was likely up and down the country over the next few days.
Heavy rain and strong winds are already causing flooding and travel disruption across Scotland, and Scotrail reporting delays on a number of routes.
Very strong winds could also affect north-west Scotland between noon and 21:00 on Sunday, including the possibilities of power cuts and delays for high-sided vehicles and public transport.
The Met Office said there could be gusts of 60-65mph (97-105km/h), up to 70mph (113km/h) on exposed coasts and hills.
During the day they will ease across England and Wales but they will stay strong across Scotland and Northern Ireland into the evening, and there could be gusts of 75mph (121km/h) across the Western Isles and up to 70mph on the west coast.
Lifeguards rescued a man at 05:00 GMT on Saturday morning after his yacht was capsized by a "large freak wave" off the Isles of Scilly, south-west England.
Falmouth Coastguard's helicopter and an RNLI lifeboat rescued the French man and his 34-foot yacht six miles from the coast.
Ian Guy, duty controller at the National Maritime Operations Centre, said the yachtsman described being hit by a "large freak wave" which capsized, rolled and disabled the vessel.
He said the man was not injured.