Current forecast models from the Met Office and European ensembles indicate a likely overnight minimum of 12–13°C in London on September 10, driven by light southwesterly winds, increasing cloud cover that limits radiative cooling, and dew points around 10–11°C that curb further temperature drops. These conditions follow a mild September 9 with clearing skies, keeping the air mass stable near seasonal norms where the 1991–2020 average low sits at 11.9°C. Traders assign the highest implied probabilities to 12°C and 13°C because ensemble spreads remain narrow, though modest uncertainty persists around exact cloud timing and urban heat island effects that could push readings slightly higher. Official resolution will hinge on verified minimum observations, with the next model runs expected to refine guidance before midnight.