National Weather Service forecasts for San Francisco on August 4 project a high near 72–74°F under mostly sunny conditions with a moderate marine layer and onshore flow typical of the region’s summer climate regime. This consensus supports the market’s tight distribution, with the 72–73°F bin leading at 28% implied probability ahead of the 74–75°F and 76–77°F outcomes. Small variations in wind strength, timing of any afternoon clearing, or model adjustments to the 500 mb ridge position could shift the official maximum across these adjacent bins. Historical August maxima average 70–73°F at downtown stations, so current guidance reflects near-normal conditions without strong offshore warming. Updated NWS and model guidance issued overnight will provide the next key data points ahead of tomorrow’s resolution.