**Current forecast consensus from NWS and major models points to an overnight low of 78–81°F in Houston on September 12, 2026, with the 78–79°F bin holding the highest market-implied probability at 52%.** This aligns with the latest guidance showing a warm, humid southerly flow and dew points in the mid-70s that limit radiational cooling under partly cloudy skies. Scattered afternoon thunderstorms may occur but are unlikely to produce enough evaporative or advective cooling to drop the minimum below the upper 70s. Supporting context includes the absence of any strong cold front or drier air intrusion, consistent with late-summer climatology where Houston’s September average low is near 75°F yet recent model runs have trended warmer. The 71°F-or-below outcome at 29.5% reflects residual uncertainty from possible heavier rain or model spread, while higher bins (84°F+) capture tail risks if clouds and moisture trap more heat. Traders are weighting the primary driver—persistent Gulf moisture and southerly winds—most heavily, as these conditions have held steady in the latest 48-hour forecast updates.