UK set for coldest night of autumn so far

UK set for coldest night of autumn so far By Sarah Keith-Lucas, Lead Weather Presenter After a period of unusually mild weather, the UK is poised for its coldest autumn night to date, with the first frost of the season expected Wednesday night as colder air moves in from the Arctic. Minimum temperatures could fall to just one or two degrees above freezing by dawn Thursday in many areas. Alongside the temperature drop, much‑needed rain is forecast for England and Wales. The jet stream, which has remained to the north and allowed mild south‑ or south‑westerly winds across the southern British Isles, will shift farther south this week. This change will steer winds more northerly, ushering in a colder air mass. Although the chill will feel noticeable compared with recent weeks, particularly in the south, temperatures are expected to be close to seasonal averages—or slightly below. Wednesday’s daytime highs are projected to reach 12 °C to 14 °C in Northern Ireland and Scotland, and 14 °C to 16 °C in England and Wales. Overnight lows on Thursday should hover around 5 °C to 7 °C for most locations, while the coolest spots in northern and eastern England and eastern Scotland may dip to only one or two degrees above zero, raising the chance of frost on grass and car windscreens. Rainfall will begin Wednesday as a frontal system moves eastward, starting cloudy and wet. While sunshine may return to many areas in the afternoon, persistent showers are likely across East Anglia and the far south‑east for much of the day. Southern and eastern England, which have been especially dry, could receive 20 mm to 30 mm of rain—equivalent to up to half a month’s typical precipitation in just 24 hours. Nearly three‑quarters of England and all of Wales remain under drought conditions. The Environment Agency has previously stated that 20 % more rainfall than average is required for at least seven months before those areas can be considered out of drought. The cold conditions will linger into Thursday, with maximum temperatures ranging from about 11 °C to 16 °C from north to south. Despite plenty of dry and bright spells, daytime sunshine may still feel pleasant for many. By Friday, westerly winds will bring milder air back across England and Wales, allowing temperatures to climb again—potentially reaching 20 °C in the east. Further north, no frost is expected Friday morning, and daytime highs should settle in the mid‑teens Celsius. Readers can follow the extended outlook in BBC Weather’s Monthly Outlook.