UK Set for Warm Weekend, but September Heatwave Unlikely

Temperatures across the UK are anticipated to climb over the coming weekend, creating summer-like conditions in various regions. While the air will feel warm and humid, particularly under sunny spells, heavy rain remains a component of the forecast. This warmth is expected to linger into Monday in many areas, although no locations are projected to meet the specific thresholds for a heatwave.

Met Office Lead Weather Presenter Ben Rich noted that while computer models indicate a mixed outlook for the latter part of September, there are currently no definitive signs of a prolonged heat event. Rain is expected to move southwards on Saturday, clearing from Scotland and Northern Ireland by afternoon but potentially affecting parts of northern England, Wales, and the Midlands. These showers may be heavy, accompanied by thunder, lightning, and brisk south-westerly winds.

Southern England is forecast to remain largely dry with sunny intervals, seeing temperatures reach the mid-20s Celsius—several degrees higher than the typical September average. On Sunday, rain may persist in the south before clearing to reveal a dry afternoon with light winds across much of the UK. While temperatures in the north may dip slightly, parts of Wales, the Midlands, and southern England could see highs of 23C to 25C. Monday promises to be the warmest day, with temperatures potentially reaching 22C to 26C in England and Wales, and around 20C in Scotland and Northern Ireland.

Despite these elevated readings, the conditions fall short of heatwave criteria, which require three consecutive days of temperatures exceeding a specific threshold: 25C in Scotland and Northern Ireland, rising to 28C in the London area. Looking ahead, the jet stream is expected to steer areas of low pressure across the UK, bringing continued unsettled weather with rain and blustery winds. This precipitation could be beneficial for the extensive areas in England and Wales currently experiencing drought.

Later in the month, high-pressure systems may begin to exert more influence, offering drier spells and above-average daytime temperatures. However, forecasting at this distance carries significant uncertainty, and current data does not suggest a heatwave is imminent. As autumn progresses and nights lengthen, high pressure could instead result in chilly mornings. Residents are advised to monitor local conditions via BBC Weather online and the application.