Forecasts from the Met Office and other models indicate a minimum temperature near 17–18°C for London on August 16, reflecting mild overnight conditions under generally settled high-pressure influence with light winds and limited cloud cover that moderates radiative cooling. Slight variations in ensemble model runs—particularly around the timing of any clearing skies or residual moisture—create the tight spread between these two leading outcomes, as small differences in boundary-layer mixing or urban heat retention can shift the exact low by 1°C. Historical August climatology supports overnight lows in this range when daytime highs reach the mid-20s, while any increase in cloud or a weak frontal passage could push values toward 16°C. Updated model guidance and observational data through the evening of August 15 will be the key near-term drivers of further shifts in trader positioning.