Forecasts from the National Weather Service and ensemble models indicate overnight lows clustered in the mid-50s for San Francisco on August 29, driven by persistent marine layer stratus, cool Pacific upwelling, and light onshore westerlies that limit radiational cooling. This aligns with the long-term average low of 56°F and recent August readings mostly between 55–58°F at SFO, keeping the 56–57°F and nearby 52–55°F buckets as trader favorites despite the elevated implied probability on 49°F or below. Variable marine layer depth and wind speeds introduce modest uncertainty in the exact minimum, with clearer or windier conditions potentially allowing slight additional cooling while stronger fog keeps readings anchored near the seasonal baseline.