**Recent Met Office and European model guidance points to a maximum of 22–23 °C for London on 30 August 2026, directly supporting the market’s heaviest weighting on those two outcomes.** Southwesterly flow ahead of an approaching Atlantic front is expected to limit daytime warming while maintaining mild conditions, with widespread cloud and scattered showers or drizzle through the afternoon keeping surface temperatures from rising much higher. Forecasts show afternoon peaks near 21–23 °C under mostly cloudy skies and moderate southwest winds of 10–20 km/h, consistent with late-August climatology when unsettled patterns suppress extremes. Ensemble guidance shows low spread around this range, with only small upside risk if breaks of sun develop; downside risk is similarly limited absent stronger cold advection. Traders have therefore priced 23 °C as the modal outcome (49.5 %) and 22 °C as the next most likely (33 %), reflecting the tight consensus in official short-range forecasts issued 28–29 August. Updated model runs and the Met Office’s next public briefing remain the key near-term catalysts that could shift implied probabilities.