London's official maximum temperature reached 16°C on October 10, 2026, according to Met Office observations, driving the market's near-certain pricing for that exact outcome. Autumnal conditions featured moderate Atlantic airflow and limited daytime heating under variable cloud cover, keeping readings aligned with seasonal averages around 14–17°C rather than unseasonal spikes. Forecasters noted no significant warm advection or clear-sky radiative warming that could have pushed highs higher. The resolution hinges on verified station data, with only extreme measurement revisions or station anomalies capable of altering the recorded peak.