Recent numerical weather prediction runs and Saudi Arabia’s National Center for Meteorology seasonal outlook for 1–1.6 °C above-normal July temperatures in the Makkah region form the main driver behind the tightly bunched 37–39 °C probabilities. Coastal humidity from the Red Sea typically caps afternoon maxima a few degrees below inland values, producing model consensus around 37–38 °C for July 10 with modest day-to-day variability from steering flow and any Shamal intrusions. Traders weigh this baseline climatology—July mean daily maxima near 38–40 °C—against short-range ensemble spread and the potential for slight model shifts before the observation window closes, keeping the three central outcomes within a few percentage points.