British Isles weather, September 2017

Mist, fog and haze was widespread across S Scotland, England and Wales by dawn on the 27th. Overnight rain had been widespread, and heavy in places, in W Ireland. 38 mm of rain fell at Valentia in the 12 hours ending 0600 GMT. The rain area moved E'wards during the day, with only a few parts of NE Scotland remaining dry by late evening. It was a warm day ahead of the rain - while few places away from N Scotland and the North Sea coasts saw much sunshine. (Gravesend 21.9C, Dalwhinnie 12.5C maximum, Santon Downham 5.9C minimum, Derrylin Cornahoule 35.0 mm, Altnaharra 4.4.h.)

Frontal rain cleared much of E Britain during the morning of the 28th - which dawned after a very mild night in SE England - but the rain lingered during the day across the Northern Isles. Parts of Ireland, Wales and Cent England had mist and fog forming before dawn but once these and the rain had cleared a day with sunny spells followed. During the afternoon further frontal rain spread across Ireland and into W Scotland, while another area of rain edged into SW England. (Santon Downham 21.1C, Lough Fea 12.2C maximum, Derrylin Cornahoule 6.0C minimum, Coningsby 15.0 mm, Shobdon 8.5 h.)

A deep low moving N'wards to the W of Ireland on the 29th pushed outbreaks of frontal rain across all areas during the day - following a mild night in parts if Cent S England and the Channel Islands. Behind the rain (falls of which were mostly light or moderate) showers and sunny spells followed. Some thunder was observed in parts of Ireland and SW Scotland, and it was a mild day in SE England with 20C reached in places. (Gravesend 20.6C, Tulloch Bridge 13.2C maximum, Redesdale Camp 7.4C minimum, Achnagart 15.4 mm, Ronaldsway 9.7 h.)

Most areas saw some rain at times during the 30th - these being heavy for a time in the morning in Cumbria and parts of N Wales. It was a cloudy day across Wales and SW England - elsewhere the precipitation was interspersed with sunny intervals at times. However, the best of the sunshine tended to be found across Scotland with rain spells lingering longer in the S. (Holbeach 18.4C, Dalwhinnie 11.3C maximum, Redesdale Camp 2.6C minimum, Shap 40.6 mm, Dyce 9.7 h.)