Recent National Weather Service and model guidance point to a high near 66–67°F for San Francisco on September 22, driven by persistent onshore westerly flow and a strengthening marine layer that favors afternoon cloud cover and modest temperatures several degrees below the 70.6°F climatological average. Recent cooling after the early-September heat wave has reinforced this pattern, with limited inland warming expected under light southwest winds. Trader-implied probabilities remain tightly clustered because small shifts in cloud timing, wind strength, or marine intrusion depth can easily move the daily maximum across the 64–69°F range, while extremes above 72°F or below 62°F appear less likely absent major forecast changes. Updated NWS model runs and afternoon observations will provide the next key data points before resolution.