The UK could see temperatures soar to 26°C in late September, according to mid-range weather models. WX Charts data, using Met Desk information, shows the warmest spot at 6pm on September 20 could be around Peterborough and Wisbech in Cambridgeshire.
A large swathe of England could see 24–25°C, stretching from Grimsby and Scunthorpe in the north to London in the south and Worcester to the west. Wales and western parts of England are likely to be cooler, with 20–21°C across Wales and 19–23°C in Devon and Cornwall.
However, the Met Office's long-range forecast for September 15–24 indicates that the unsettled theme is likely to continue initially, with showers and brisk westerly winds. There is a low risk of stronger winds and heavy rain around mid-week, but later in the period, more settled and drier spells may develop, particularly in southern parts of the UK.
Temperatures are expected to be close to average or slightly below, but could recover to a little above average if dry weather persists. Netweather's forecast for September 15–21 suggests ridges of high pressure moving east across southern Britain, bringing dry, sunny spells, while more changeable conditions persist in northern and western Scotland.
Mean temperatures are forecast to be near the long-term normal in western Britain, but about 1°C above normal in eastern Scotland and England. Unusually high sea surface temperatures around the British Isles, following a record warm spring and summer, may offset below-average temperatures elsewhere.
