Current National Weather Service and ensemble forecasts indicate a high near 89°F for Miami on September 6, driven by typical late-summer humidity, southeasterly flow, and afternoon sea-breeze convergence that favors scattered thunderstorms after midday. These storms can suppress further warming once initiated, favoring the tightly matched 88-89°F and 90-91°F bins as traders weigh the precise timing and coverage of convection against climatological September averages of 89–90°F. Recent model runs show modest spread in boundary-layer moisture and wind shear, creating genuine uncertainty around whether peak readings occur before or after storm onset; clearer morning conditions or delayed development could briefly push into the low 90s, while earlier or more widespread activity would cap readings nearer 88°F. Official Miami International Airport observations will resolve the market.