Forecast models show a broad ensemble spread for Madrid’s minimum temperature on October 13, keeping outcomes from 11°C to 18°C nearly equal in trader-implied probability. This uncertainty stems from variable nocturnal radiative cooling under evolving high-pressure influence, possible Atlantic moisture increasing cloud cover, and subtle differences in low-level wind direction that affect cold-air pooling in the city basin. Mid-October climatology places typical minima near 10–12°C, yet current synoptic guidance favors a milder pattern with limited cold advection. Fresh runs from the European Centre for Medium-Range Weather Forecasts and Global Forecast System over the next 24–48 hours will narrow the range ahead of market resolution.