**Trader sentiment for the lowest temperature in San Francisco on August 29, 2026, centers on the 56–57°F range (74.5% implied probability) because official forecasts and historical norms converge on a mid-50s overnight low at the NOAA station (KSFO).** National Weather Service and model guidance project a low in the mid-50s amid persistent marine-layer stratus, light-to-moderate onshore westerly flow, and typical late-August coastal upwelling that moderates radiational cooling. Ensemble spreads from GFS and ECMWF show only modest variability in boundary-layer moisture and wind, keeping the most probable outcome tightly clustered near the long-term average low of 56.0°F for the date. Supporting ranges such as 54–55°F (24%) or 50–51°F (34%) reflect residual uncertainty in exact minimum timing and any brief clear-sky windows, while probabilities drop sharply below 52°F or above 58°F due to the stabilizing marine influence. No recent developments—such as anomalous heat, stronger offshore flow, or model shifts—have moved the consensus away from this narrow band. Resolution will hinge on the official KSFO minimum once the full daily observation is finalized.