A yellow weather warning from the Met Office will remain in effect across parts of eastern England until 7am BST on Friday.
The severe weather warning follows heavy rain, frequent lightning, hail and powerful wind gusts across the region.
Further showers and periods of rain are forecast throughout the day, with heavy downpours and thunderstorms most likely across western Scotland, Wales and north-west England.
Rain and unsettled weather could spread eastwards later, bringing a risk of thunderstorms to north-east England and eastern Scotland.
Following recent warm and humid conditions, temperatures on Friday are expected to feel cooler and more comfortable.
Temperatures are forecast to reach 20-23 degrees Celsius (68-73 degrees Fahrenheit) across England and Wales, while Scotland and Northern Ireland could see highs of 16-20 degrees Celsius (61-68 degrees Fahrenheit).
These temperatures are close to the average for late August.
Source: www.bbc.co.uk