**Recent model guidance from the Met Office and other global ensembles points to an overnight low near 17°C for London on July 25, 2026, amid a post-heatwave cooldown.** After early-July peaks near 35°C, a shift toward more typical summer conditions—with a mix of clear spells and increased cloud cover—has kept nights mild but introduced modest forecast spread. Ensemble members cluster between roughly 15–19°C, reflecting uncertainty in boundary-layer mixing, wind speeds, and the precise arrival of any Atlantic moisture or high pressure ridge. This scientific uncertainty directly explains the tight clustering of market-implied probabilities around 18°C (46.5%), 17°C (36%), and nearby values, while the 14°C-or-below outcome at 37% captures residual tail risk from stronger cooling scenarios. Key resolution factors include the exact minimum recorded at official stations (typically Heathrow or St James’s Park) and whether any brief clear, calm period allows greater radiational cooling. Updated model runs and Met Office briefings over the next 48 hours will likely narrow the range as the event approaches.