Recent ensemble guidance from Météo-France and ECMWF places the most likely overnight minimum in Paris on May 20 in the 10–14 °C range, with probabilities spread across adjacent buckets because of lingering model spread on cloud cover and boundary-layer mixing four days ahead. A broad ridge of high pressure is expected to limit daytime heating while allowing variable radiational cooling overnight, modulated by light northerly flow that has kept mid-May temperatures 1–3 °C below the 1991–2020 climatological average of roughly 11 °C. Clearer intervals could push the low toward 9–10 °C, whereas increased low-level moisture or a weak frontal passage would support 12–14 °C readings. No strong consensus yet exists on exact timing of any clearing, which explains why the market shows nearly equal weighting from 10 °C through 16 °C and minimal probability assigned below 8 °C. Updated model runs over the next 48 hours will narrow the distribution ahead of resolution.