Recent model consensus from European forecasts points to a minimum temperature in Paris on August 19 near 18°C, consistent with the market’s tight clustering around 17–19°C outcomes. Following a mid-August heatwave, a shift to milder Atlantic air and increased cloud cover is limiting nocturnal radiative cooling, keeping lows elevated relative to seasonal norms of 15–16°C. Key variables include the degree of overnight cloudiness, which reduces temperature drop, and local urban heat-island effects at official measurement sites such as Paris-Montsouris. With resolution only two days away, any late adjustment in high-resolution guidance on boundary-layer moisture or wind could shift the final reading by 1°C, explaining the balanced probabilities across the leading bins.