September warmth: a possibility, but not a promise
As the UK moves into September, the Met Office has indicated that some warmer temperatures could return during the month, though any hot spells are likely to be brief. The national forecaster's long-range outlook for the period covering September 6–15 suggests an unsettled stretch is likely, with showers or longer spells of rain affecting many areas. Rain is expected to be most frequent across northern and western regions, while the south and east may see drier interludes. The forecast also notes the potential for strong and gusty winds, particularly in the northwest, and says temperatures are likely to be near average, with brief warm or very warm spells possible, especially in the south.
In its outlook for September 1, the Met Office forecast dry and bright conditions across southern areas, with cloudier skies further north and a few showers, adding that more persistent rain would reach Cumbria by late afternoon. Temperatures were expected to be around average but feeling pleasant in any sunshine, with a maximum of 20°C. The long-range forecast for mid-September onwards carries very low confidence, according to the Met Office.
Weather maps point to a possible warm day
Weather maps from WXCharts, which use Met Desk data, suggest that temperatures could surge back to nearly 30°C on Tuesday, September 15. By midday, southern regions are expected to see temperatures around 27°C, with London set to be the warmest spot in the country. Hertfordshire, Bedfordshire and coastal areas including Brighton are also predicted to reach 27°C.
Further north, cooler conditions are anticipated, with Manchester and its surrounding areas likely to sit at around 20°C. By 6pm, temperatures are forecast to climb across the country: London, Berkshire, Surrey and parts of West Sussex could reach 29°C, while areas stretching up towards Northamptonshire are expected to hit 27°C. Oxfordshire looks set to reach 26°C, with much of the Midlands enjoying a comfortable 25°C, and Greater Manchester and parts of Yorkshire may see a modest rise to 23°C.
Heatwave criteria not expected to be met
The Met Office officially declares a heatwave when temperatures hit the "heatwave threshold" for three consecutive days. In the south-east, where conditions are typically warmer, this threshold is set at 28°C, meaning the forecast temperatures for September 15 would meet heatwave criteria for that day. However, given that the warm spell is not anticipated to persist, an official heatwave declaration currently appears unlikely.
A summer of heat
The summer just past was reported as the hottest on record, with the Met Office confirming the season's record-breaking status. Temperatures exceeded 30°C on several occasions across the UK. Liverpool reached heatwave conditions multiple times over the summer, drawing people to nearby beaches and seaside towns.
Local outlook for the week ahead
For Liverpool, the Met Office's week-ahead forecast indicates mixed conditions: Tuesday September 1 brings sunny intervals and a moderate breeze with 21°C; Wednesday September 2 sees heavy rain with 21°C; Thursday September 3 has light rain showers at 21°C; Friday September 4 is light cloud at 19°C; Saturday September 5 brings sunny intervals at 19°C; and Sunday September 6 sees light rain with 22°C.
As September unfolds, the picture is one of variability: while the south may catch some warm days, the overall pattern is likely to remain changeable, with no sustained heatwave in sight.