Current forecast guidance from NOAA and AccuWeather points to overnight lows in Miami on August 19 clustering around 78–81°F, aligning with the market’s leading bins of 80–81°F (31.5%) and 78–79°F (27.5%). Persistent warm Atlantic and Gulf waters, high humidity, and light winds limit radiational cooling under typical subtropical summer conditions, while scattered afternoon thunderstorms may further moderate temperature drops. Model consensus shows modest day-to-day variability driven by sea-breeze timing and cloud cover, keeping the distribution tight around the long-term August average low near 79–80°F. Traders are pricing in this narrow range because resolution hinges on the official Miami International Airport reading, where small shifts in steering flow or dew-point advection could tip the outcome between the top two bins.