The Met Office has issued a yellow warning for heavy rain and thunderstorms for Dorset today.
The 'be aware' warning, which is valid from just after 12 noon today until 9pm this evening, says: "Heavy showers and thunderstorms, already scattered across some western areas, will become more widespread during the day.
"The focus of the heaviest downpours will tend to shift eastwards by late afternoon and evening, allowing some improvement across the western slice of the warning area. The public should be aware of the risk of localised surface water flooding, with the added hazard of lightning in some areas.
A spokesperson for the Met Office said: "An unstable and moist flow across southern parts of Britain will provide the basis for some intense showers through today, and with the winds lighter than recent days, these will last longer where they do occur, perhaps producing in excess of 30 mm of rain in 2 or 3 hours in a few localities. But as so often happens on showery days, some places will escape the worst."