**Forecast uncertainty around an approaching frontal boundary and associated rainfall is the main driver behind the closely matched market-implied odds for Wuhan's September 28 minimum temperature.** Multiple numerical weather prediction models, including those referenced by the China Meteorological Administration, show a minimum near 21–23 °C under mostly cloudy skies with periods of rain or thunderstorms and light northerly winds. These conditions limit nocturnal radiative cooling while also preventing strong daytime heating, keeping overnight lows moderate. Traders appear to weigh the risk of slightly stronger cold-air advection or heavier rain episodes that could push readings to 19 °C or below against scenarios of lingering warmer, more humid air that might hold the low near or above 22–23 °C. Official station observations from the Wuhan network, expected to be finalized shortly after midnight local time on September 29, will resolve the market; updated model runs overnight may further narrow the range.