A THUNDERSTORM warning has been brought forward – potentially ending the brief spell of sunshine even sooner.

The Met Office has moved the start of its yellow thunderstorm warning from 12pm on Wednesday, July 31 until the end of Thursday, August 1. 

Previously, the warning – which covers the whole Bournemouth, Christchurch, Poole and Purbeck area – started at midnight on Thursday. 

On the Wednesday extension, the Met Office said: “Whilst many places will stay dry, a few thunderstorms are likely to break out on Wednesday.  

“These are possible at any time, but become more likely during the afternoon and evening. Where these occur, 20 to 30 mm of rain is possible within an hour, and perhaps as much as 50 mm in two hours.” 

Lightening is also possible, it added. 

And on the Thursday warning, it said the heaviest showers could result in 20-30 mm within an hour, with 24 hour accumulations possibly reaching as much as 70-90 mm where multiple showers affect the same location. 

The Mett Office added to expect: “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  

“There is a small chance of fast flowing or deep floodwater causing danger to life.” 

Meanwhile, temperatures could reach as high as 30C today (Tuesday) with the UKHSA putting out a ‘heat health alert’.