Forecast models from Météo-France and the European Centre for Medium-Range Weather Forecasts indicate Paris will reach a daily maximum of 24°C on September 30 under stable high-pressure conditions with light winds and limited cloud cover. This consensus drives the market’s 99.7% implied probability for 24°C, aligning with late-September climatology and current observational trends. Ensemble runs show tight agreement on the peak value, with resolution hinging on official station readings rather than forecasts. Only an unexpected warm-air advection or measurement anomaly could shift the outcome, though such developments remain outside the latest model guidance.