Saturday
Low pressure will bring patchy outbreaks of rain, some heavy and perhaps thundery, to southern parts of England and Wales early in the morning, spreading northwards across Ireland into Northern Ireland before developing more widely through the day. Best of the driest weather across northern and northeast Scotland. Drier conditions and developing sunshine through the afternoon for far southern and southeastern parts of England. Highs at 17 to 24C yet feeling humid, particularly the south and southeast.

Saturday Night
Showers continue into the evening and overnight for some, the showers from the daytime looking to become more confined further north and northeast. More showers or longer spells of rain are expected to push in to southern and southwestern areas of England as well as Wales later. Largely dry elsewhere with variable cloud amounts. Lows at a rather muggy 11 to 16C.
 

Sunday
Sunday keeps low pressure to the west of Ireland. Expect sunny spells and thundery, heavy showers across mainly England and Wales in the morning with some showers further north, then heavier showers spreading into central and western Scotland regions as the day progresses. Far northern and eastern areas of Scotland currently looking to stay largely dry. Sunny spells and showers also across Ireland and Northern Ireland. Highs at 16 to 23C.

Monday
A rapidly developing Atlantic low pressure system tracks towards southern parts of Ireland and southwest England through the day. This will bring spells of rain, some heavy, to Ireland, much of England and Wales as it pushes northeastwards through the day. Further north, expect some sunny spells and showers, although cloud will gradually thicken from the south. The low will continue to track north and into northern England and Scotland overnight. Winds will strengthen too. Highs at 15 to 21C.