Yellow weather warnings are also in force more generally across eastern and southern England and Wales where the thunderstorms could be just as severe but more localised.
Into Saturday there will be more showers and thunderstorms across western parts of England, Wales and into Scotland where there is a further yellow severe weather warning.
The yellow warnings for thunderstorms are in place in:
The heat and humidity has been building gradually, especially across northern and eastern parts of England where temperatures are expected to peak on Friday afternoon.
While 30C could be reached in the Norwich area, more widely across East Anglia, eastern and south-east England, temperatures will be in the mid to high-twenties.
These temperatures are around 7 to 10C above average for the time of year.
With the rising humidity and heat, thunderstorms will bring the end to the hot spell.
Temperatures will be lower on Saturday with highs like low to mid-twenties across eastern England and high teens elsewhere.
