**Coastal moderation from the Red Sea, combined with typical early-summer atmospheric conditions, positions 37–38°C as the most probable peak range for Jeddah on June 15.** Jeddah’s location on the eastern Red Sea shore introduces persistent onshore flows and higher humidity that frequently cap daytime maxima a few degrees below inland Saudi stations, even under clear skies and strong insolation. Recent model guidance and climatological baselines show June average highs near 36–38°C at King Abdulaziz International Airport, with observed peaks this month already reaching 40°C earlier in June before moderating. Current forecasts from sources such as timeanddate and BBC indicate 35–37°C for the 15th under sunny to mostly sunny conditions, while longer-range ensembles allow for modest warming if northerly flow weakens. The market’s 39.5% implied probability on 38°C or higher reflects trader weighting of the upper end of this uncertainty band, consistent with historical variability and the timing of final model updates before resolution.