Recent National Weather Service and AccuWeather guidance points to a high near 72–77°F for San Francisco on August 4, 2026, as a strong inland heat ridge weakens and allows greater marine-layer influence along the coast. Persistent onshore flow and the typical summer sea breeze are expected to limit afternoon warming at official stations, keeping readings clustered in the low-to-mid 70s despite the broader regional heat event that peaked earlier in the week. Model consensus favors modest cooling relative to August 1–3, though small differences in fog clearance timing or wind strength can shift the daily maximum by several degrees. Historical August maxima average 69–73°F, so the current spread of market-implied probabilities across the 72–77°F bins reflects genuine forecast uncertainty around the strength of the marine layer and any residual offshore warming. Updated NWS discussions and 00Z/12Z model runs tomorrow morning will provide the clearest signal ahead of resolution.