Forecast models from sources like the GFS and ECMWF indicate Jeddah's August 21 maximum will likely peak in the mid-to-upper 30s°C range, with trader consensus split between 37°C and 38°C amid narrow spreads in ensemble outputs. Persistent summer high pressure, minimal cloud cover, and light winds favor strong daytime heating along the Red Sea coast, though the moderating maritime influence and typical afternoon sea breezes cap extremes compared to inland areas. Historical August averages near 38°C provide baseline context, while small differences in predicted humidity, exact wind timing, or boundary-layer mixing explain the close probabilities across 36–39°C outcomes. Updated model runs over the next 48 hours will likely tighten resolution criteria tied to official observations.