Storm Claudia is expected to bring up to a month’s-worth of rain in a day as heavy downpours batter parts of England and Wales..
Amber warnings for “persistent and heavy” rain come into force from noon on Friday until the end of the day and cover parts of Wales, the Midlands, the south-west, the south-east and east of England.
In England, some places could have 80mm of rain, while parts of Wales may experience 100-150mm on the higher ground, or 50-75mm generally across the region, the Met Office warning said.
All of this may be “exacerbated” by strong easterly winds, as well as thunderstorms later on Friday, the forecaster added.
Storm Claudia, named by the Spanish Meteorological Agency, has already brought heavy rain and strong winds to Spain and Portugal.
A separate and existing yellow warning for rain covers much of England, from Cheshire and North Yorkshire to the south coast, for a 24-hour period from 6am on Friday, and a warning for winds of up to 70mph in some western areas of the UK is in place from noon until midnight.
The Met Office said there could be power cuts, travel disruption and damage to buildings.
Travellers are urged to be cautious as a large swath of central and southern England and Wales on Friday into Saturday will be soaked.
The slow-moving downpours mean some areas could have up to a month’s-worth of rain in 24 hours, according to the Met Office chief meteorologist, Matthew Lehnert.
He added: “Much of this will fall on saturated ground, increasing the chances of flooding and contributing to the amber warnings we have issued. Within the amber warning areas, some could see in excess of 150mm accumulate during the event, with 60-80mm fairly widely.
“Gusty winds in the north-west of England and north-west Wales is an additional hazard, with 60-70mph gusts possible in exposed places within the warning area.”
Unlike many named storms, Claudia is not expected to directly cross the country, and instead will maintain its position in the west, the Met Office said.
The Environment Agency said there could be some surface water and river flooding in the north of England. It said it had been working with emergency services and local authorities to ensure they were fully prepared for when the storm hits on Friday.
The flood duty manager, Ben Lukey, said: “Storm Claudia will bring heavy prolonged rainfall across parts of England, with significant surface water flooding probable across parts of central England on Friday. River flooding impacts are also possible tomorrow and into Saturday.”
By Friday morning, the agency had issued three flood warnings – where flooding is expected – in the north-west of England, with more than 100 alerts in place around the country.
The Scottish Environment Protection Agency had a flood warning in place for Glen Lyon in Perthshire, while Natural Resources Wales has issued 20 flood alerts.
In Devon, flooding between Exeter and Barnstaple is expected to affect trains until Sunday, with a reduced service on Chiltern Railways on Friday when CrossCountry, London Northwestern and West Midlands services are likely to be hit by the bad weather.
In the north of the country, the weather is expected to turn colder, with overnight frost in places from Friday to Sunday.
