Short-range NWS and model guidance point to a highest temperature near 68–70°F in San Francisco on August 20, driven by persistent onshore marine flow and a shallow marine layer that limits daytime heating under mostly cloudy skies. Typical August climatology features average highs around 67°F at KSFO, with sea breezes and stratus keeping the city cooler than inland areas; recent forecast discussions show only minor day-to-day fluctuations and no strong ridging or offshore winds to push readings higher. Trader consensus clusters on the 68–71°F brackets because ensemble guidance and local observations consistently favor this range absent anomalous warming. Final NWS point forecasts and real-time observations on the 20th will resolve the market.