Two yellow weather warnings for rain and thunderstorms have been issued for today (May 18).
The first alert for storms covers most of the south of England and is in place between noon and 9pm.
A Met Office spokesperson said: "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
"There is a small chance of fast flowing or deep floodwater causing danger to life and there is a small chance that some communities become cut off by flooded roads
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"Where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services."
During Wednesday's storms, the M5 was hit with flash flooding, and around 150 properties had their electricity cut in Bristol and North Somerset.
A yellow weather warning for rain is also in place for the Midlands today, between 3am and noon.
It reads: "Flooding of a few homes and businesses is likely.
"Bus and train services probably affected with journey times taking longer
BBC forecaster Louise Lear said Thursday will welcome even more "heavy, persistent rain" moving into East Anglia, the Midlands and then into the north as the day goes on.
"And behind it, yet more thundery downpours are likely," added Ms Lear.
"Some of these really could be quite intense, with light winds, slow moving. We could see a couple of inches of rain perhaps in two to three hours."
Heavy rain is predicted for most of the day in Bristol on Thursday. And it will feel cooler with the mercury peaking at 16C.
UK Met Office forecast
Thursday:
Early showery rain over England and Wales becoming confined to western regions later and perhaps spreading into eastern Northern Ireland and southern Scotland. Sunny spells and thundery showers following.
Outlook for Friday to Sunday:
A mixture of scattered showers, periods of rain, and sunny spells. Driest for most on Saturday. Light winds at first, these increasing from the west through Saturday. Generally rather warm.
