**Clear skies and light winds under high pressure are positioning the lowest temperature in Madrid on August 28 around 12–13°C, aligning with the market's top outcomes (13°C at 47.5% and 12°C at 37.5%).** Current GFS-based and European model guidance shows overnight radiative cooling under mostly clear conditions, with minimums forecast near 12–13°C (roughly 54–55°F) in the pre-dawn hours before temperatures rebound under sunny daytime conditions. This follows a cooler, more unsettled period on the 27th and contrasts with Madrid’s late-August climatological average low of about 18°C. Historical records indicate 12.3°C as the all-time August 28 low (1956), so the current setup sits near the cooler end of recent variability without reaching extremes. Traders are assigning the highest implied probabilities to 12–13°C because ensemble spreads remain narrow around these values, with limited upside from stronger winds or cloud cover and only modest downside risk from further model cooling. Resolution will hinge on the official station reading (typically Retiro or Barajas), where even small forecast adjustments from the final model runs could shift probabilities between the two leading bins.