Official observations from the King Abdulaziz International Airport weather station—the market's resolution source—confirm Jeddah's highest temperature peaked at 41°C during mid-afternoon hours on April 18, 2026, under dominant high-pressure subsidence and light southerly winds typical of Red Sea coastal spring patterns. This observational data, corroborated by hourly METAR reports showing temperatures climbing to 41°C before evening cooling, has solidified trader consensus at near-100% implied probability for 41°C, as diurnal maxima rarely exceed this late in the day amid dropping solar insolation. National Center for Meteorology warnings of scattered thunderstorms across western Saudi Arabia, including Jeddah, introduced brief uncertainty but failed to produce sufficient cloud cover or precipitation to suppress the peak. Realistic challenges would require a final NCM daily bulletin revising upward based on validated late data, though standardized protocols and current evening readings below 35°C make this improbable.