**Forecast consensus from regional models points to a nocturnal minimum near 29°C in Jeddah on September 28, aligning with the market's leading 49% implied probability.** Late-September conditions feature high humidity (often 70-90% overnight), light northwest winds, and marine influence from the Red Sea that moderates radiative cooling under mostly clear skies. This keeps lows close to the climatological average of ~29°C rather than allowing sharper drops. A 23°C-or-below outcome at 41.5% would require unusual factors like stronger northerly advection or clearer, drier air than currently projected. Resolution hinges on the exact 24-hour minimum recorded at official stations, with traders weighing model spread against historical variability in Red Sea coastal temperatures.