Forecast models for Jeddah on August 25 show close agreement on peak daytime heating near 37–39 °C under typical late-summer high-pressure conditions, with minor differences arising from subtle variations in wind direction, boundary-layer mixing, and Red Sea moisture advection. Recent observations indicate daytime maxima around 38–39 °C, consistent with the August climatological average high of approximately 37–38 °C and the absence of any strong synoptic forcing. The tight clustering of market-implied probabilities around 38 °C (32.5 %) and 39 °C (28.5 %) reflects this ensemble spread and inherent uncertainty in 48-hour temperature forecasts, where small changes in cloud cover or sea-breeze timing can shift the daily maximum by 1–2 °C. Updated runs from global and regional models will likely narrow the range ahead of resolution.