Current short-range ensemble forecasts for Jeddah show a narrow spread of daily maximum temperatures centered on 40–42 °C, which directly explains the closely matched market shares for those outcomes. Coastal humidity from the Red Sea, combined with light northerly winds typical of mid-May, limits rapid warming while allowing modest daytime heat buildup under mostly clear skies. Historical observations from the Saudi National Meteorological Center place average May highs near 38 °C, yet recent upper-level ridging over the Arabian Peninsula has supported slightly above-normal readings in the past week. Model spread between the European Centre for Medium-Range Weather Forecasts and Global Forecast System runs remains the main source of uncertainty, with any shift in wind direction or cloud cover likely to tip the final value by 1–2 °C.