The Met Office has issued an urgent weather warning, with motorists warned of difficult driving conditions.
A yellow warning for thunderstorms has been issued covering London and parts of the south coast and Wales.
The warning is in place from 8pm today and is expected to last until 8am tomorrow, Thursday, May 2.
Forecasters from the Met Office have warned of possible power outages as well as some road closures.
Thunderstorms are expected to hit the UK
PA/Met Office
A Met Office spokesperson said: "Spray and sudden flooding could lead to difficult driving conditions and some road closures.
"Where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services.
"There is a slight chance that power cuts could occur and other services to some homes and businesses could be lost.
"There is a small chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes, hail or strong winds."
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Thunderstorms are likely later this evening and overnight in London, Brighton, Oxford and other areas covered by the second warning, which comes into effect at 11pm tonight and lasts until 6am tomorrow.
Looking ahead to the week after, Britain is set to see some sunny weather, with temperatures set to rise.
Meteorologist for British Weather Services and social commentator, Jim Dale said: "The next week or so is likely to bring the warmest day of the year so far, and we are going to see a change from the current cold as we lose the northerly drag.
"There are going to be fronts coming through, so it is not completely settled everywhere, but there will be a change from the dominant low pressure we have seen now for months. We are about to undo the run of cold, wet and windy weather."
The UK could soon witness thunderstorms later this week
PAIt will wrap up an unusually chilly end to April which saw the mercury in parts of Scotland dip below freezing.
Forecasters were even mooting the risk of snow over the northern mountains at the weekend as the region shivered under winter frosts.
It follows an unusually choppy storm season which has seen 11 named storms –the latest Kathleen at the start of April – swipe the UK since September.
