Parts of the UK could be lashed with rain and thunder following the last day of meteorological summer.
Forecasters said Thursday would be dry and fine for many but cloud will increase across the south of England and Wales, with some scattered showers developing by the afternoon.
These could turn heavy and thundery in the south, according to the Met Office. Looking ahead to Friday, forcasters say any early patches of mist and fog will clear.
Any early patches of mist and fog will clear. Then mainly dry and bright with spells of sunshine however there will be large areas of cloud cover around and a threat of showers developing which may be locally heavy and will be most frequent in the north and west.
Saturday will be dry for most, but there will be areas of thick cloud cover and a threat of showers or spells of rain and some of these may be on the heavy side.
The Met Office has issued a yellow weather warning for rain in Northern Ireland on Saturday. There is a “small chance” that homes and businesses could be flooded, causing damage to some buildings, it said.
Spray and flooding could also lead to difficult driving conditions and some road closures. The areas of heavy rain are expected to pulse northwards across much of Northern Ireland and the southwest of Scotland through Saturday, potentially accompanied by thunderstorms.
The worst affected areas could see 30-40mm of rain in the space of just two to three hours.
Sunday will be overcast with cloudy skies and there will be outbreaks of rain which will be mostly across northern and western areas.
