**Persistent tropical moisture, high dew points in the mid-70s, and widespread cloud cover from daily thunderstorms are keeping overnight lows elevated in Miami, supporting the market's tight clustering around 76–79°F for the September 23 minimum.** Official forecasts from the National Weather Service and private models show a minimum temperature in the mid- to upper-70s under a pattern of south or southwest winds at 5–10 mph, with 70–90% chances of showers and thunderstorms both days. These conditions limit radiational cooling at night, a common feature in late-September South Florida when the atmosphere holds abundant moisture from the Gulf and Atlantic. Model consensus points to a low near 75–77°F, with slight variations depending on exact timing of any clearing or rainfall. The 76–77°F and 78–79°F bins together hold nearly 70% of the market-implied probability, reflecting this narrow expected range. Lower outcomes (72–73°F or below) would require an atypical dry slot or stronger northerly flow, while warmer readings would need sustained mixing or delayed cooling—scenarios models currently assign lower odds. Upcoming NWS updates and morning model runs over the next 24–48 hours will refine the exact minimum, particularly any adjustments to wind direction or moisture profiles that could shift the outcome within the leading bins.