**Mild southwesterly flow and limited overnight radiative cooling under variable cloud and showers are positioning the lowest temperature in London on August 30 near 15–17°C.** Official Met Office guidance shows a daytime high near 23°C with an overnight minimum of 15°C, while ensemble and high-resolution models (including hourly outputs from sources like yr.no) indicate early-morning readings bottoming out around 14–16°C amid light-to-moderate winds and periods of broken cloud. Recent above-average warmth across August has kept the broader air mass mild, but the approach of an unsettled Atlantic pattern with showers is expected to limit clear-sky cooling that would otherwise produce lower values. Trader consensus reflected in the market—16°C at 45.5% implied probability, followed by 17°C (32%) and 18°C (22%)—aligns closely with this forecast range, as the urban heat-island effect and station-specific measurement (typically Heathrow) often add 1–2°C relative to rural analogs. Key variables that could shift outcomes include the exact timing and coverage of overnight cloud or rain, which would suppress the minimum, versus any clearing that allows further cooling toward 14°C or below. Updated Met Office and ECMWF runs over the next 24–48 hours, plus any revisions to wind or cloud forecasts, represent the primary near-term catalysts for market movement ahead of resolution.