Scotland is already feeling the force of Storm Abigail, with reports of flash flooding leaving cars floating along streets. Weather warnings have been issued amid fears that lightening, heavy downpours and near-hurricane winds of up to 90mph will cause chaos across the country.

The Met Office has upgraded the earlier yellow alert to an amber severe weather warning for Friday (13 November), with the north-west and north of Scotland and the Northern Isles expected to bear the brunt first.

Chief meteorologist Paul Gunderson said: "In terms of impact, the Western Isles, north of Scotland and Orkney could see winds of 90mph with potential impacts upon transport and maybe power supplies too. We could see quite a lot of lightning as well and high tides, so with that in mind we have upgraded to amber."

The weather system - named Abigail - is forecast to bring gusts of between 60-70mph for the whole of Scotland, reaching as high as 90mph in the far northwest across exposed locations and a months rainfall is expected in the space of 48 hours.

Some areas of northern Wales and northwest England could see as much as 200mm of rain between Saturday afternoon and the early hours of Monday. "This amount of additional rainfall falling on to already saturated ground is likely to lead to flooding, either from standing water, or from rivers bursting their banks," the Met Office said.

Motorists have been warned to expect disruption on the roads and problems with power supplies from 9pm on Thursday, up until Friday afternoon. The motoring group RAC said: "The 'invisible' force of the wind can lead to vehicles unexpectedly being knocked off course, sometimes with devastating consequences."

Scottish ferry operator CalMac has advised travellers to think carefully about their plans this weekend as large waves are expected. Operations director Drew Collier said: "There is a clear warning that major weather related disruption to ferry services on the Clyde and Hebrides routes is likely later this week. I would urge people to factor this in when making travel plans. The sea conditions we are expecting could well be too treacherous to sail in."

All schools in Shetland and the Western Isles will be closed tomorrow due to concern over strong winds and the possibility of lightning strikes.

The long-lasting effects of the storm could cause commuter chaos on Monday and experts have warned that the storm is just the beginning of a cold front that could herald the first snowfall of winter.

Storm Abigail is the first weather system in the UK to be given a name following a campaign by the Met Office and its Irish counterpart, Met Eireann, to raise awareness about safety when severe weather is forecast.