Is Another UK Heatwave Possible in September?

The United Kingdom has endured an exceptional summer, with current data indicating it is likely to be the hottest on record. This summer has seen an increased likelihood of heat spikes and heatwaves, a trend predicted by meteorological services earlier in the year, partly attributed to human-induced climate change.

While the current week brings more unsettled weather and lower temperatures, some long-range forecasts are hinting at the possibility of further dry and sunny spells extending into September. This has fueled speculation about another potential heatwave, which would be the sixth of the year. Even with the recent cooler conditions, the overall mean average temperature for the year remains on track to surpass last year's record.

Several factors could contribute to a warmer spell in September. Computer models suggest high pressure may establish itself south of the UK early in the month, typically leading to dry, sunny weather and potentially drawing warmth from continental Europe. Additionally, dry soil conditions, a result of July being the driest on record for England and Wales, can cause air temperatures to rise more rapidly as less energy is lost to evaporation. Warmer sea surface temperatures around the UK, currently about 3C above average, also 'load the dice' for warmer weather.

Meteorological summer concludes on August 31st, marking the transition to autumn. Predicting weather patterns during this transitional season can be more challenging. However, the combination of lingering summer warmth, dry ground, and potentially favorable atmospheric pressure systems means the possibility of continued warm weather, including another heatwave, cannot be ruled out.