Traders see the highest temperature in Jeddah on June 16 most likely falling between 37–39 °C because the latest ensemble runs from global models show a tight spread around the mid-June climatological maximum, with the 38 °C outcome edging ahead on recent guidance. Primary scientific drivers include the strength of the Red Sea trough, daytime sea-breeze suppression of inland heat advection, and boundary-layer mixing that modulates the daily peak. Small differences in forecast timing of any upper-level ridge or low-level wind shift can easily swing the maximum by 1–2 °C, keeping the three central bins nearly tied. Updated high-resolution model output and local station observations expected over the next 48 hours remain the key catalysts that could consolidate or further diffuse these probabilities.