Saturday
A vigorous area of low pressure affects the British Isles. Strong to gale force winds most areas, gusts 35-45mph inland, but locally 50-60mph coasts & headlands in the south-west. Much lighter winds in Scotland. Heavy showers spread eastwards through the day, merging into near-constant rain in the west. Isolated thunder. Sunny spells in the south-east, best in the morning. Often dry in northern Scotland after early rain. Highs 17 to 21C.

Saturday night
Areas of heavy showers continue into the night, slowly becoming confined to coastal areas in the west of England & Wales, but some bursts will push well inland on the fresh breeze. Pulses of heavy rain may also pivot back into Scotland from the east. Occasional clear spells in central areas of Britain. Winds will remain strong, particularly around coasts in the south. Temperatures 10 to 14C, locally 7C or below in north-west Scotland.

Sunday
Low pressure fills slowly toward the east, but another low approaches from the Atlantic. Showers, some heavy bursts moving west to east, most frequent in the morning, but fading from west. Rain may also persist for a time in north-east Scotland. Occasional sun. Fronts moving in from the west through the day bring rain and murky conditions to Ireland, later Wales & the south-west. Remaining breezy. Highs 18 to 23C, warmest south-east.

Monday
Low pressure to the north-west and a slow moving frontal system across central & northern Britain. Risk of persistent rain for Wales, northern England and perhaps the Midlands, heaviest over western hills. Patchy rain for Scotland & Northern Ireland. A lot of cloud overall, although some sun may break through in southern England, where it will feel humid. Mostly light winds, sea breezes. Highs 17 to 20C north; 22 to 25 south.