Householders and businesses are counting the cost of the wave of freak weather that followed yesterday's record-breaking temperatures.
And forecasters have warned there is more hail, thunderstorms, torrential rain and localised flooding to come tomorrow evening.
More than 50,000 people in the north-east of England had their power cut following yesterday's storms, a nursery owner in North Yorkshire watched as up to 5,000 greenhouse panes were smashed by giant hailstones, dozens of cars were damaged by the hail and a house in County Durham lost its roof to a blaze, apparently following a lightning strike.
The storms that swept over the north of England and Scotland yesterday evening provided spectacular light shows just hours after many places recorded their hottest July day ever.
The Met Office said the 34 hour period to 10am this morning saw 19,525 lightning strikes, 15,273 of which were in Scotland.
Temperatures dipped a little today but are expected to rise again tomorrow until the evening when, according to a Met Office severe weather warning, there could be torrential downpours with large hail and lightning leading to possibility of localised flooding.
Jonny Bradbrook, of Ravensworth Nurseries, Richmond, North Yorkshire, said his business was a scene of devastation after huge hailstones smashed thousands of planes of glass in his greenhouses.
Mr Bradbrook said the storm arrived at around 9pm yesterday and only lasted for 20 minutes, but left thousands of pounds of damage.
He said: "I've never known anything like it. They were as big as golf balls. I think there might be 5,000 panes gone but I'll know for sure later."
Mr Bradbrook said many of the panes were left with "bullet holes" and the broken glass has also wrecked some of his stock.
He said: "We've had floods before but nothing like this. There was no rain, just hail and thunder."
Giant hailstones are also reported to have caused damage to scores of cars in parts of the Yorkshire Dales and County Durham.
AA Insurance confirmed it had received a spate of claims for cars damaged by hail, particularly in north-east England.
A spokesman said one claimant said his Jaguar "looked like a golf ball it had so many dimples on the roof and bonnet" after being caught in a severe storm.
Also in the Durham area, a house fire which left a property in Ferryhill without a roof has been blamed on a lightning strike. No one was hurt in the blaze.
The thunderstorm which hit the north-east of England left 57,500 homes without electricity in parts of North Yorkshire, County Durham, Tyne and Wear, Teesside and Northumberland.
Northern Powergrid said 500 engineers worked to restore power and, tonight, only a few dozen customers were still without electricity.
Scores of motorists pulled over to watch last night as another storm moved up the Pennines.
In Sheffield, weather-watchers drove out of the city to witness the huge cloud which silently flashed with almost continuous lightning but with no thunder and no rain.
In the village of Worrall, Rick Taylor, said: "I've not seen anything like this before, it's amazing. It's exactly like that scene in Close Encounters of the Third Kind when the spaceship is approaching."
The light show gradually worked its way north, with people using social media to chart its progress through Huddersfield and then on to Leeds, Bradford and the Yorkshire Dales.
Leeds North West MP Greg Mulholland said on Twitter: "What an amazing spectacle of nature. I hope it's not like Day Of The Triffids."
The Met Office confirmed today that temperatures hit the record July high of 36.7C (98.1F) in Heathrow at 3.13pm yesterday afternoon - breaking the previous record of 36.5C (98F) set on July 19 2006 in Wisley, Surrey.
Many other parts of England also saw the thermometer top the 30C mark with 35.3C (95.5F) at Wittering, in Cambridgeshire, 30.7C (87.3F) at Bainbridge, in the heart of the Yorkshire Dales, and 32.1C (89.8F) at Gringley-on-the-Hill, in Nottinghamshire.
The Met Office said tonight it expected temperatures to rise again tomorrow but not quite to the levels of yesterday.
In its summary for tomorrow, it said: "Southern England, central areas and South Wales should see temperatures in the mid to high 20s while further north we expect temperatures to be in the high teens to low 20s."
It said the yellow "be aware" severe weather warning for tomorrow runs from 7pm to noon on Saturday.
The warning said: "Isolated heavy, and possibly severe, thunderstorms are expected to develop on Friday evening across parts of England and Wales.
"These are likely to become more frequent later and spread northwards towards southern Scotland. Some torrential downpours are possible leading to localised surface water flooding, with large hail and frequent lightning also possible hazards."