Friday
Slack pressure and light winds across the British Isles. Many places will see dry weather with a mix of cloud and sun, cloud tending to fill in inland across the country whilst many coasts stay sunnier. Local slow-moving heavy showers forming with a risk of thunder, most likely eastern England, the north-east, plus central Scotland. Patchy rain encroaches into southwest England, heavier later for Cornwall. Feeling quite humid, highs 18 to 24C, warmest eastern England.

Friday night
Local showers will tend to fade into the night, although some will linger for central-eastern Scotland, plus Norfolk and around The Wash. Areas of rain are expected to move across southern England, may persist for a few hours, some heavier bursts. A mix of cloud and some mist patches across the country, but also some clear spells, best toward the west and northwest. Wind mostly light, breezy around some coasts. A mild, quite humid night, lows 10 to 15C.

Saturday
A very slack pressure pattern affects the British Isles resulting in little wind. Many areas will remain dry, but expect areas of slow-moving showers to break out, most widely into the afternoon, some heavy and thundery bursts possible locally. Some places seeing an hour or more of rain. Most showers are likely over northern England & Scotland. A zone of more persistent rain for a time in the far south and southeast in the morning. A lot of cloud. Highs 16 to 22C, quite humid.

Sunday
Low pressure located to the west of Britain pushes a frontal system across the country to bring a lot of cloud and areas of rain. Most persistent in the north and west, patchier toward the east, although a few heavy showery bursts could run across the Midlands. Driest for longest in East Anglia and the southeast before a few showers develop later. South to southwesterly breezes, strongest in the west. Highs 16 to 23C.