Official observations from London City Airport confirm a daily maximum of 22°C on October 4, reached during afternoon hours under clear, stable high-pressure conditions with light westerly winds. This aligns precisely with the market's 100% implied probability for 22°C, as real-time hourly readings showed steady warming to that threshold without exceeding it, consistent with seasonal baselines around 17–18°C and recent model consensus. Trader consensus reflects this verified data from authoritative monitoring, with minimal uncertainty given the event's completion. Only a significant revision in official Met Office or Heathrow records—such as through calibration adjustments—could realistically alter resolution, though cross-station agreement makes that improbable.