**Recent forecasts position the overnight low in London on August 26 around 16–19 °C, aligning with the market’s leading outcomes of 17 °C (42 %) and 18 °C (31 %).** Official guidance from the Met Office and other models shows a mild southwesterly flow ahead of low pressure, with increasing cloud, humidity, and a chance of showers or drizzle that limit nocturnal radiative cooling. This follows a period of above-average warmth in August 2026, where recent nights have already seen minima in the 10–12 °C range under clearer conditions; the expected cloud cover on the 25th–26th should keep temperatures several degrees higher. Model consensus points to a minimum near 17–18 °C at standard stations such as Heathrow, consistent with climatological averages adjusted for the current warm, unsettled pattern. Key variables that could shift the outcome include the exact timing and coverage of any showers or breaks in cloud, which would be clarified by updated ECMWF and Met Office runs on the 25th. The market’s tight clustering around 16–18 °C reflects traders incorporating these near-term forecast details and the reduced likelihood of stronger cooling.