The Westcountry's longest heatwave in seven years is set to end in spectacular fashion this week, with the sizzling heat and humidity giving way to thunderstorms, torrential rain and even hail.
The Mediterranean-style weather is likely to peak today with temperatures exceeding 30 degrees in the South West before the dramatic change.
Storms are due to arrive in the region tonight, bringing thunder, lightning and heavy downpours of rain and hail.
Up to 50mm (two inches) of rain could fall in just a few hours tomorrow, leading to a risk of localised flooding.
The Met Office has issued a severe weather warning, telling people in the South West to "be aware" of rain on Tuesday and Wednesday.
Helen Chivers, spokesman for the Exeter-based weather centre, said the latest forecast signalled "something of a change" from long spells of unbroken sunshine.
"The high pressure system is moving away and is being replaced by low pressure, which means an end to the fine spell of weather we've been having," she said.
Mrs Chivers predicted the thunderstorms would affect many parts of Devon and Cornwall tonight, leading to "potentially heavy downpours" across the region over the following 48 hours.
Unsettled weather is likely to return later in the week and during next week, with spells of sunshine mixed with heavy rain and potentially thunder.
"There are some people who are desperate for rain," Mrs Chivers added.
Sweltering conditions are set to continue today, with highs of 28 degrees in the region before the current weather system moves away.
The storm forecast comes after the longest sustained period of hot, dry weather since 2006, when temperatures hovered in the late 20s and at times reached 30 degrees.
The Met Office issued a level three heatwave warning in the South West last week as concerns grew for the health of vulnerable people.
Emergency services were given a busy weekend, with numerous people getting into difficulties while out and about enjoying the tail end of the fine weather.
A 72-year-old paraglider was helped off a section of beach near Shaldon, South Devon, after he landed in a bay with the tide coming in on Saturday afternoon. And a man in his 50s needed rescuing from rocks at Wembury earlier in the day after his catamaran capsized off the South Devon coast.
On the north coast, four people were taken to safety at around 8am after their boat lost power near Ilfracombe in North Devon.
Also on Saturday a yachtsman made a mayday call at around midnight after his 23ft vessel ran over fishing gear two miles off the Cornish coast near Mevagissey. Crew members from Fowey RNLI spent around two-and-a-half hours bringing the man and his yacht to safety, due to tricky offshore conditions.
Another midnight rescue saw a man returned to the mainland after becoming stranded on Beggars Island, near Saltash in Cornwall.
The hot weather has provided a welcome boost to the Westcountry's tourism industry, with more than a million holidaymakers and daytrippers expected to have visited the region over the weekend.
Robin Barker, who leads Devon-based company Services for Tourism, said: "The heatwave has been absolutely fantastic for the industry.
"But we would like a bit of rain. If you were on holiday in the Caribbean, you would expect the odd tropical storm.
"The weather forecasts have been fair and accurate, but it's important the media report the weather in a balanced way," he added.
A chief forecaster at the Met Office explained that the change in the weather would be caused by low pressure mixing with the current "plume of hot, humid air".
"The developing set-up on Tuesday and Wednesday provides the ingredients for more widespread and energetic storms.
"Large rainfall totals, falling in short periods and on to hard-baked ground, may lead to flooding locally, with hail a possibility," he said.
The changeable weather is likely to continue into August, with the southern part of the country likely to see better weather than elsewhere.
Temperatures are predicted to drop during the first few days of the month, but remain warm at times in the south.