Recent forecast guidance from models such as ECMWF and GFS points to a maximum of 38–39 °C in Jeddah on June 18, driven by a persistent heat ridge over the Hejaz region tempered by Red Sea sea breezes that typically cap coastal highs 2–4 °C below inland values. High humidity from the adjacent marine layer reduces evaporative cooling while keeping the actual dry-bulb temperature in the upper 30s, consistent with June climatology averaging near 36 °C. Ensemble spreads remain modest, with some runs showing brief 40 °C spikes if onshore flow weakens and others holding at 37 °C under stronger northerlies. Traders have therefore concentrated probability on the 38 °C and 39 °C bands, reflecting the narrow window between typical coastal moderation and modest synoptic warming expected before the market resolves.