**Current model consensus and climatological norms point to overnight lows in San Francisco on September 8 clustering in the mid-to-upper 50s°F to low 60s°F, aligning with the closely matched market-implied probabilities around the 56–61°F bins.** San Francisco’s coastal location means temperatures are strongly modulated by the marine layer, onshore westerly flow, and stratus clouds that often limit radiational cooling overnight. Historical averages place the September 8 low near 56°F, with records rarely dipping below 50°F or exceeding 65°F in early September. Recent model runs from sources such as the National Weather Service, European ensembles, and private forecasters show limited spread, with most solutions keeping the minimum in the 54–62°F range under typical late-summer pressure patterns and no strong offshore or downslope warming expected. The notable tail probabilities for 49°F or below and 68°F or higher reflect residual model uncertainty in marine-layer depth and exact wind trajectories, plus the possibility of brief clear-sky radiational cooling or unexpected warming if the thermal trough shifts. As the event nears, updated NWS forecast discussions and high-resolution model runs (e.g., HRRR, NAM) will likely narrow the distribution further by refining cloud cover and boundary-layer moisture. Traders should monitor any shifts in the 500-hPa pattern or marine-layer inversion strength, which directly influence whether the low settles near the 56–57°F or 60–61°F bin.