Current forecast models from the Met Office and ensemble guidance point to overnight lows of 13–16°C in London on September 1, 2026, under mostly dry, partly cloudy conditions with light westerly winds that limit strong radiative cooling. This aligns with the market's leading 13°C outcome at 41% implied probability, as typical early-September climatology (average low near 12.8°C at Heathrow) combines with a transitional high-pressure pattern that prevents both extreme chill and sustained warmth. Recent model runs show minimal disagreement on the minimum, though any increase in cloud cover or wind could push readings toward the 14–15°C range favored by secondary probabilities.