A weather warning for thunderstorms and heavy rain has been issued for Kent.
The Met Office has issued a yellow alert from now until 10pm tonight.
It covers most of England, and experts are warning of heavy rain and lightning.
In some places, there may be up to 20-30 mm of rain within 2-3 hours and strong winds with at times 40pmh gusts.
Meteorologists say there may be short-term loss of power and delays to train services.
It is likely driving conditions will be affected by spray, standing water possibly hail leading to longer journey times by car and bus.
Homes and businesses could suffer flooding and cause damage to buildings and structures.
A Met Office spokesperson said: “Consider if your location is at risk of flash flooding. If so, consider preparing a flood plan and an emergency flood kit.
“Give yourself the best chance of avoiding delays by checking road conditions if driving, or bus and train timetables, amending your travel plans if necessary.
“People cope better with power cuts when they have prepared for them in advance. It’s easy to do; consider gathering torches and batteries, a mobile phone power pack and other essential items.
“If you find yourself outside and hear thunder, protect yourself by finding a safe enclosed shelter (such as a car). Do not shelter under or near trees, or other structures which may be struck by lightning. If you are on an elevated area move to lower ground.”
