LONDON - Thousands of Britons woke up to flooding and power cuts on Christmas morning after torrential rainfall and hurricane-force winds battered the country.

Three severe flood warnings are in place along with over 350 secondary warnings and alerts, largely across southern and central England, Britain's environment agency said on Wednesday.

Tens of thousands of people, mostly in southern England, had no electricity late on Christmas Eve and engineers were working on Christmas Day to restore power.

Winds of up to 90 mph (145kph) hit both Britain and France on December 23 and Christmas Eve, with heavy downpours causing cancellations of rail, flight and ferry services.

Five people - including a man who tried to rescue his dog from a river - have died in Britain over the last three days due to the high winds and heavy rainfall.

Police in Dorset, southwest England, evacuated over 100 residents in the early hours of Wednesday in two separate locations following fears of flooding from a nearby river.

At London's second airport Gatwick, power cuts - which caused angry scenes between passengers and staff on Tuesday - continued as stranded travellers tried to catch flights on Christmas Day.

"Due to adverse weather in the last 48 hours there are still power outages in parts of our North Terminal, these are causing delays to departing flights," said a message on the airport's website.