Recent forecast models from Météo-France and European ensembles indicate a persistent cool, unstable pattern over Paris through May 17, driven by lingering low-pressure influences and widespread cloud cover that limits daytime solar heating. This setup favors a daily maximum in the 15–17 °C range, with ensemble means clustering near 16 °C under light winds and modest humidity. Historical mid-May climatology shows average highs around 18–19 °C, yet current conditions deviate due to the slow-moving trough suppressing warm advection. Traders weigh the narrow spread among 15 °C, 16 °C, and 17 °C outcomes against subtle model differences in afternoon cloud breaks and boundary-layer mixing, which could shift the peak by 1–2 °C depending on exact timing of any brief clearing.