London - Britain faced travel chaos on Monday and 30 000 homes were without electricity in north-western France as a massive storm swept in from the Atlantic Ocean.
Britain's national weather centre the Met Office warned of falling trees, damage to buildings and disruption to power supplies and transport as the storm hit England's southwest coast late Sunday.
Between 20 and 40mm of rain were predicted to fall within six to nine hours as the storm tracked eastwards across Britain, with a chance of localised flooding.
It will be followed by widespread gusts of 97 to 113km/h across southern England and south Wales on Monday, with winds reaching more than 130km/h in some areas, forecasters say.
The Met Office issued an "amber" wind warning for the region, the third highest in a four-level scale, and urged people to delay their Monday morning journeys to work to avoid the worst of the bad weather.
In northwest France 30 000 homes were without electricity early on Monday, said the ERDF distribution network, after wind gusts reached 133km/h in some areas knocking down power lines but no major damage or injury were reported.
London looked set for a chaotic rush-hour after train companies First Capital Connect, C2C, Greater Anglia, Southern and Gatwick Express services all said they would not run services on Monday until it was safe to do so. That is unlikely to be before 09:00, according to forecasts.
Robin Gisby from line operator Network Rail warned commuters to expect severe disruption.
"If we get through this in the morning, restore the service during the afternoon and are able to start up a good service on Tuesday morning, in the circumstances I'll be pretty pleased," he added.
Major airports also warned of disruption to flights with London hub Heathrow expecting approximately 30 cancellations.
Cross-channel train service Eurostar said it would not be running trains on Monday until 07:00, meaning delays to early services.
Several ferry operators said they had cancelled some cross-Channel services and Irish Sea crossings.
Meanwhile, the rough conditions led to rescuers standing down the search for a 14-year-old boy who was washed out to sea from a beach in East Sussex on England's south coast.
Britain last experienced similar wind strengths in March 2008, but forecaster Helen Chivers told AFP the expected damage was more comparable with a storm seen in October 2002.
Prime Minister David Cameron received an update from officials on contingency planning in a conference call on Sunday, amid fears of similar damage wrought by the "Great Storm" of October 1987.
That left 18 people dead in Britain and four in France, felled 15 million trees and caused damages worth more than $1.6bn as winds blew up to185km/h.
Martin Young, chief forecaster at the Met Office, said: "While this is a major storm for the UK, we don't currently expect winds to be as strong as those seen in the 'Great Storm' of 1987 or the 'Burns Day storm' of 1990.
"We could see some uprooted trees or other damage from the winds and there's a chance of some surface water flooding from the rainfall, all of which could lead to some disruption."
Veteran weather forecaster Michael Fish also said Sunday's storm was unlikely to be as severe as 26 years ago, although his comments will be taken with a pinch of salt in Britain.
Fish was the BBC's main television weatherman in 1987 but famously denied that a major storm was on its way just hours before it hit.
This year's storm has been named St Jude after the patron saint of lost causes, whose feast day is on Monday.