**Recent Met Office forecasts and supporting model guidance indicate a daytime maximum of 22–23 °C for London on 30 August 2026, aligning with the market’s heavy weighting toward those two outcomes (61.5 % and 37.0 %).** Southwesterly flow across the UK is advecting mild Atlantic air while increasing cloud cover and the chance of scattered showers in the afternoon, which limits further surface heating. With solar insolation already declining in late summer, these conditions cap the peak temperature near the seasonal average of roughly 21–22 °C. Current observations show temperatures rising through the morning into the low 20s °C, consistent with the latest guidance that keeps the daily high below 24 °C. Breezy conditions further enhance mixing and prevent stronger warming. Traders are therefore assigning negligible probability to extremes above 24 °C or below 21 °C, reflecting the narrow uncertainty range typical of a well-resolved short-range forecast. Any late-day shower development or subtle shifts in cloud timing could still nudge the exact maximum between 22 °C and 23 °C, which explains the split between those two leading contracts.