Recent Met Office and UKMO model consensus points to a peak temperature of 21–22°C in London on September 24 under high pressure, with mostly clear skies and light southerly winds allowing strong daytime radiative heating. Ensemble spreads arise mainly from small differences in low-level cloud timing and boundary-layer mixing depth, which can shift the afternoon maximum by 1–2°C. Current runs favor 22°C as the most likely outcome, consistent with climatological September highs near 19°C but elevated by the persistent anticyclonic pattern. Traders assign nearly equal implied probabilities to 21°C and 22°C because model updates through the next 48 hours could still alter the precise peak before resolution criteria are met.