Recent Met Office and European model guidance points to a minimum temperature near 17–19°C in London on June 28 amid a post-heatwave cooling trend, with high pressure giving way to increased cloud cover and lighter winds that limit overnight radiative cooling. Trader consensus clustering on 18°C (45.5%) and 19°C (36%) reflects this narrow range, while the 15°C-or-below option at 19.5% accounts for possible clearer skies enhancing heat loss. Key differentiators include forecast variability in low-level humidity and boundary-layer mixing, which can shift the minimum by 1–2°C, alongside the typical 1–2°C urban heat-island effect in central London versus airport sites used for official readings. Updated model runs over the next 24–48 hours will likely tighten these probabilities ahead of resolution.