Friday
Heavy rain across northern areas in the morning will move slowly northwards, but may persist in eastern Scotland most of the day. Murky with patchy rain for central areas, whilst scattered thunderstorms may break out in the south-east by afternoon. Brighter and fresher conditions develop from the west, accompanied by a strong north-westerly breeze. Dry with sunshine for Ireland. A humid 25C in south-east England, but cool at 16 to 19C elsewhere.
Friday night
Patchy rain and thunderstorms will clear away into the North Sea on Friday evening, leaving most places dry, and skies clearing. Scattered showers may affect north-western parts of Ireland. A fresh west to north-westerly breeze, particularly around coastal areas. Overnight lows 8 to 12C, locally lower in sheltered northern valleys.
Saturday
Pressure builds slowly from the south-west, giving a dry and bright day for most of Britain and Ireland. Scattered light showers toward the north-west. Sunny spells developing. Light westerly winds. Feeling fresher than recent days in the south. Rather cool in the north and west, highs of 16 or 17C, reaching 19 to 21C in central and southern regions.
Sunday
Slack high pressure across the British Isles will bring mainly dry conditions and light winds. Brightest skies toward the east. Thicker cloud across western regions. Small risk of patchy rain encroaching into south-western parts of Britain and Ireland. Chance of one or two drizzly showers over northern hills of Britain. Temperatures between 17 and 22C.