**Forecast models and real-time observations from agencies like the Met Office and Open-Meteo consistently indicate a daytime maximum of 22°C for London on October 4, 2026, under stable high-pressure conditions with light westerly winds and mostly cloudy skies.** This alignment across multiple runs, including hourly data showing afternoon peaks near 21–22°C, has driven overwhelming trader consensus toward that exact outcome. Historical context reinforces the positioning, as the long-term average high for the date is around 17.5°C while the all-time record stands at 22.9°C. Late-day confirmation of these conditions leaves little room for revision, though an unanticipated increase in cloud cover or a sharp wind shift could still cap readings slightly lower.