**Recent National Center for Meteorology (NCM) seasonal guidance for above-normal temperatures across western Saudi Arabia, including the Makkah region encompassing Jeddah, underpins the market's elevated odds for 39–40°C+ outcomes on August 18.** The agency projects anomalies up to 2–2.5°C above the long-term August average (roughly 38°C daytime highs), driven by persistent high-pressure patterns and reduced cloud cover typical of late-summer Red Sea coastal conditions. Short-range model runs show a narrower spread around 37–39°C, with BBC and timeanddate.com guidance currently favoring 37–38°C under mostly sunny skies and moderate northerly winds. However, the 47% implied probability on 40°C or higher captures residual uncertainty from ensemble divergence and the documented seasonal warming signal, while lower bins reflect climatological baselines and recent model consensus. Traders are weighting the official climate outlook more heavily than individual deterministic forecasts two days out, consistent with how prediction markets aggregate skin-in-the-game assessments of forecast skill near the resolution threshold.