**Trader consensus strongly favors a 13°C minimum in Paris on September 11, 2026, at 97.5% implied probability.** Current GFS-based forecasts and observational data indicate overnight radiative cooling under mostly clear to partly cloudy skies will drive the daily low to this level, aligning with the 1991–2020 climatological average low near 12°C and recent September patterns. High pressure and light winds favor efficient heat loss after daytime highs around 24–25°C, with dew points supporting surface temperatures in the low teens Celsius by early morning. Scenarios that could realistically shift the outcome include increased cloud cover or a stronger southerly flow raising the minimum above 14°C, though model agreement remains tight on the current trajectory with limited uncertainty in the final hours of the day.