Recent forecasts from multiple models, including ECMWF and GFS runs, indicate a high near 16–18°C for Munich on September 22 under mostly cloudy skies and light northwesterly flow, consistent with the market’s tight clustering of probabilities around those values. A weakening high-pressure ridge over central Europe is yielding to cooler maritime polar air advected behind a passing cold front, with reduced insolation from increased cloud cover limiting maximum temperatures relative to the late-September climatological average of 18.8°C. Ensemble spread and minor differences in boundary-layer mixing and timing of any residual clear spells create the narrow differentiation among 16–20°C outcomes, while probabilities drop sharply outside this range due to the low likelihood of strong warming or further cooling in the final model updates.