Recent Met Office guidance positions a 27°C maximum as the most probable outcome for London on July 27, citing high pressure and largely sunny conditions that limit cloud cover while preventing the stronger southerly flow seen during the earlier July heatwave. Ensemble forecasts show modest spread around this value, with some guidance reaching 28–29°C if daytime heating is enhanced by the urban heat island effect, while others settle near 26°C under slightly cooler northeasterly breezes. The summer’s 1.8°C above-average mean temperature has kept baseline warmth elevated, yet the post-heatwave cooling trend and stable ridge of high pressure support the market’s clustering around 26–28°C. Updated model runs and any Met Office briefing on July 26–27 will provide the clearest near-term signal for resolution.