Winds of up to 75mph (120km/h) will lash parts of south-west England as Storm Evert, the first storm to be named in the month of July, hits the UK on Thursday and Friday.
The Met Office said the newly named storm would bring “unseasonably strong winds and heavy rain”.
Warnings are in place for parts of the south of England and Wales, with damage to infrastructure and travel disruption thought possible.
Forecasters announced Evert as the name for the storm on Thursday morning, advising the public to be “weather aware”.
They predicted wind gusts of between 45mph and 55mph in some coastal and hilly areas, rising to 65-75mph gusts across Cornwall.
The Met Office’s principal operational meteorologist, Dan Suri, said: “Storm Evert will bring some high winds, particularly along the northern coast of the south-west, but there will be gusty winds more widely in southern areas, which brings the potential for some impacts, especially for those that might be travelling or camping in the weather.
“Storm Evert will move eastwards across southern UK during Friday daytime, clearing into the North Sea during Friday evening.
“As well as the high winds, there will also be some heavy rain before it leaves our shores, with up to 40mm possible over parts of Wales and the south-west and the potential for 40 or 50mm rain in a short period of time from heavy, possibly thundery, showers over parts of eastern and central England on Friday afternoon.”
The low-pressure system is moving in from the west on Thursday evening, with the highest winds expected to be over parts of Cornwall during the early hours of Friday, when gusts could reach as high as 75mph in the most exposed areas.
There will also be high gusts in other coastal areas in southern parts of England and Wales, mainly between 40 and 60mph, and this brings the chance of some travel disruption and damage to temporary structures, the Met Office said.
The high winds will be accompanied by rain at times, with the wettest weather on Thursday night expected over parts of Wales and south-west England. Parts of eastern, southern and central England will then get the wettest weather on Friday, including a risk of thunderstorms in a few places during the afternoon.
The government announced on Thursday that more than £860m will be invested in flood prevention schemes across the UK over the next year.
Evert is the first storm to be named in the month of July by the Met Office, although named summer storms are not unprecedented. In 2020, Storm Ellen hit on 19-20 August, before Storm Francis moved over the UK on 25 August.
Drivers have been warned to take care in the storms. The RAC Breakdown spokesperson, Rod Dennis, said: “The arrival of a summer storm to the south-west could take drivers – and indeed all holidaymakers in the region – by surprise.
“The sheer strength of the wind coupled with huge volumes of traffic will make driving conditions hazardous, particularly for those towing caravans and trailers. We strongly recommend drivers check over their vehicles before setting out – ensuring roof boxes are firmly secured and try to avoid exposed coastal and moorland routes where the impacts of the wind on driving will be the greatest.
“Drivers should reduce their speeds accordingly to help ensure they complete their journeys safely.”