Trader consensus on Polymarket has locked in 19°C as the lowest temperature at Shanghai Pudong International Airport on May 13, 2026, with 100% implied probability, driven by official early-morning observations confirming a minimum of 19°C around 05:00 local time amid lingering humidity from recent frontal passages. Subsequent hourly data from the Shanghai Meteorological Observatory and international models (e.g., ECMWF, GFS) show daytime readings climbing to 30°C under partly cloudy skies and southerly winds, with evening forecasts holding above 20°C due to urban heat island effects and overcast conditions inhibiting radiative cooling. Historical May climatology supports this, as Shanghai's average low is 16–18°C, but recent warming after early-month cold snaps has stabilized minima. A realistic challenge would require sudden clearing and northerly gusts tonight, though current dew points near 19°C make sub-19°C unlikely before midnight resolution. Official daily summary expected post-00:00 UTC May 14.