**Trader sentiment for Milan's lowest temperature on September 9, 2026, centers on a tight cluster around 17–20°C (each near 42–43.5% implied probability) because official forecasts and model guidance converge on a narrow overnight minimum amid unsettled weather.** A passing frontal system has brought widespread cloud cover, thunderstorms, and showers across Lombardy, limiting nighttime radiative cooling while also advecting slightly cooler maritime air. This produces variable outcomes depending on the exact timing of precipitation, wind speeds (often 5–10 km/h from the northeast or east), and cloud persistence, which trap heat and prevent sharp drops below 17°C or allow brief clearer intervals that could push the low toward 20°C. Historical September baselines for Milan (average lows near 14–16°C) provide context, but the current synoptic pattern—marked by high humidity (80–95%) and pressure around 1010 hPa—keeps the minimum elevated. Model spreads in GFS and ECMWF runs, plus real-time observations from stations like Linate showing temperatures holding in the low 20s°C into the evening with ongoing rain, sustain the close probabilities. New hourly data or clearing trends overnight could shift the final recorded minimum and nudge the market.