Britain is set to experience a week of persistent grey skies, mist, fog, and drizzle as the weather phenomenon known as 'anticyclonic gloom' returns. This pattern occurs in autumn when a high-pressure system settles over the country, creating a stable atmosphere that prevents vertical air movement. This stability traps moisture and low-level clouds, preventing fog dispersal and blocking sunshine.
Unlike the clear, sunny weather often associated with high pressure in summer, the UK will see stratus and stratocumulus clouds linger for days. Light winds are insufficient to clear this cloud cover, leading to condensation into fog and drizzle. The low angle of the sun during this period lacks the strength to break through the gloom, resulting in dull conditions, particularly in inland areas and valleys where cold air can accumulate.
Forecasts indicate these conditions will persist for at least the next seven days. Temperatures are expected to remain stable, with London experiencing daily highs between 10C and 11C and lows of 7C to 8C. Birmingham will see daily highs ranging from 8C to 11C with lows of 5C to 6C.
Met Office chief forecaster Paul Gunderson explained that while high pressure often brings pleasant conditions in summer, it can have a different character in winter. The still air under such systems can lead to trapped mist, fog, and cloud. He noted that these persistent periods, sometimes called 'anticyclonic gloom,' typically end abruptly with the return of strong westerly winds associated with Atlantic weather systems.
The UK has experienced similar conditions previously. Last October saw one of the country's dullest Octobers on record due to 'anticyclonic gloom.' A more significant event occurred in November 2024, when a high-pressure system over Europe led to over ten days of stagnant air, resulting in virtually no sunshine in many areas and widespread mist, fog, and drizzle despite mild temperatures. That period was eventually broken by two named storms, Bert and Conall.
'Anticyclonic gloom' is also known by the German term 'Dunkelflaute,' which roughly translates to 'dark doldrums' or 'dark wind lull.' This return to gloomy weather follows a period of heavy rain in late October from Storms Austen and Boelo, which caused the country to experience its wettest week since October 2024. However, some parts of the South West and Sussex remain under a severe drought following an exceptionally dry summer, which was the UK's hottest since records began in 1884.
