**Official forecasts and real-time observations from the Shanghai Meteorological Bureau and global models show a daily maximum temperature of 24°C on September 30, 2026, under overcast skies with light rain, northeasterly winds, and high humidity typical of late-September East Asian monsoon transition.** Multiple numerical weather prediction runs converge on this value, consistent with the seasonal climatological average for the area and recent cooling trends following warmer late-summer conditions. The 100% market-implied probability reflects strong trader confidence in verified station data resolving the market. A realistic challenge would require an unforecasted late-day temperature spike above 24°C or post-event data revisions, though current model agreement and timing near resolution make such shifts improbable.