Persistent summer heat and high humidity are keeping overnight lows elevated across South Florida, with official National Weather Service guidance and ensemble models pointing to a minimum temperature near 79–81°F for Miami on August 20. Recent model runs show limited nocturnal cooling under partly cloudy skies and light winds, consistent with the ongoing pattern of daily highs in the mid-90s that has produced consecutive nights above 78°F. While scattered afternoon thunderstorms may briefly enhance mixing, they are not expected to drop temperatures into the mid-70s. This scientific context aligns with the market’s concentration of probability on the 78–83°F range, reflecting trader assessment of typical late-summer climatology and the absence of stronger synoptic cooling.