A weather warning for rain has been issued for the entirety of Brecon and Radnorshire this evening.
The Met Office has put a yellow warning in place between 6pm tonight (Tuesday) and 12 midday tomorrow (Wednesday).
The whole of Brecon and Radnorshire is included in the warning area - as is much of Wales, the borders, and southwest England.
The forecaster said: “Areas of heavy rain are expected to develop and push north across the warning area. Rain will develop in southwest England late afternoon, before becoming heavier and expanding north on Tuesday evening and overnight into Wednesday.”
The Met Office warns that many areas will see around 10-20 mm of rain, but there is a chance some locations may see considerably more than this over a six-hour period, most likely parts of southwest England and south Wales.
A few places may see 50-80 mm of rain fall in six hours.
“Isolated thunderstorms are also possible in the south of the warning area, with lightning an additional hazard,” added the forecaster.
Travel disruption is expected as a result of the weather.
There is also a slight chance of power cuts and loss of other services to some homes and businesses.