Lightning could be seen over the district at the end of the hottest day of the year in Morecambe.
Met Office figures showed temperatures peaked at 30.13 degrees celsius (86.2 degrees fahrenheit) at noon in the resort on Wednesday.
Humidity rose to 92% by midnight as thunder and lightning flashes could be seen all over the district.
Readers took dramatic photos of the lightning which began at around 11pm on Wednesday.
Lancaster and Morecambe fire crews said there were no reports of any lightning damage in the area.
In November 2013, a lightning strike in Morecambe caused electric appliances to explode all over the town. David Tarbun’s house on Lathom Avenue took the brunt of the massive bolt, described as “like a bomb going off”.
It broke nine of his windows, shattered two car windscreens and ripped a hole in the roof and front door, and caused thousands of pounds of damage to household appliances.
Wednesday, July 1 was the hottest July day in the UK on record, with temperatures hitting 36.7C (98F).
The Met Office said the highest reading had been registered at Heathrow breaking the previous record set in 2006.
Weather monitors at Hazelrigg, Lancaster University, said temperatures in Lancaster rose on Wednesday to 29.4 degrees celsius (84.9 degrees fahrenheit).
This made Wednesday the seventh hottest day in Lancaster since 1966. The hottest was 32.1 degrees celsius on August 2 1990.
Temperatures dropped in Morecambe and Lancaster on Thursday to cooler levels although weather forecasters said they were set to soar again on Friday, with sunshine and showers predicted for the weekend.