Storm Evert is gathering pace, with winds of up to 65mph expected to lash the South West on Friday.
Forecasters warned it “will get worse before it gets better” as coastal gales, rain, floods and thunderstorms are set to reach the UK.
Staycationers camping in Cornwall were forced to cut their holidays short after their tents were destroyed in the severe weather on Thursday.
One person tweeted: “Storm Evert well and truly battered our tent last night/this morning and still going strong. Time to cut the holiday short.”
Another said: “Camping during Storm Evert is the most terrifying experience of my life. Never again.”
Friday brought a “wet and windy start” for the southern and central regions, as the storm moves across parts of the UK. London is expected to experience wet and windy weather as a result of Storm Evert.
Thunderstorms and heavy showers will develop throughout Friday in parts of East England, East Midlands and Yorkshire, according to the Met Office.
A spokesperson added: “Heavy showers and thunderstorms will develop later this morning and this afternoon.
“Some torrential downpours are possible with 20 to 40 mm rain falling in some places and, perhaps, more than 70 mm rain falling in one or two spots.
“Lightning, gusty winds and hail will be additional hazards for some.”
The naming of Storm Evert comes on the day the government announced that more than £860 million is to 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’s storm naming group, although named summer storms are not unprecedented.
In 2020, Storm Ellen hit from August 19 to 20, before Storm Francis moved over the UK on August 25.