Met Office issue heatwave warning as storms set to sweep UK
18 July 2014 Last updated at 14:06 BST
Lightning struck the UK over 3,000 times in two hours as storms moved across the country overnight.
The Met Office has issued an alert for southern England and the Midlands as forecasters say Friday will be the hottest day of the year so far.
Jo Black has investigated how people are coping with temperatures of over 30 degrees and why the advice from experts may be familiar but should not be ignored.