Friday
A waving frontal trough over the west of the British Isles will edge east and weaken as low pressure, moving east-northeast in the Atlantic drives a new occluding system east into Britain and Ireland. Rain in Western Scotland, Wales and western parts of England will move east, becoming lighter and patchier as it does so with some parts of the east and southeast staying largely dry. Perhaps a few drizzly outbreaks around the south and west of Ireland in the morning, then with rain spreading from the west during the afternoon - the rain reaching Western Scotland, Wales and the west of England later in the day. This rain will be heavy at times and accompanied by strengthening south or southeast winds with gales, locally severe gales, in exposed locations. Highs 10 or 11C in the north, up to around 13C in the south in the south.

Friday Night
The wet and windy weather continues to move east, clearing all bar, perhaps, easternmost counties by the end of the night. Showers follow, chiefly into western coastal areas with the wind swinging west or southwest and moderating. Overnight lows 3 to 7C in the west, a milder 9 or 10C in the southeast.
 

Saturday
Low pressure to the northwest of Ireland moves northwest, becoming centred to the southwest of Iceland, with a showery, broadly south to southwesterly airstream becoming established. Any lingering rain in the east soon clears to give some sunshine but with showers, some of these heavy and prolonged and also with a risk of hail and thunder across Southern counties of England. Eastern areas will see fewer in the way of showers, though. Away from northern and western coasts, the stiff south or southwesterly breeze will ease. Highs 9 to 13C.

Sunday
Low pressure to the west of Ireland drifts northeast. Showers, some heavy and prolonged for western areas with a lengthier spell of rain for a time in southernmost counties of England. Drier with spells of sunshine for central and eastern parts. South or southwest winds will be fresh to strong around the coast. Highs 9 to 13C.