**Coastal marine influence and a persistent onshore flow from the Pacific are keeping San Francisco's August 1 high in the low-to-mid 70s.** National Weather Service forecasts show sunny conditions with highs near 72–75°F at downtown and airport stations, as westerly winds of 10–20 mph advect cool, stable marine air that limits daytime warming despite regional high pressure and inland heat. Model consensus favors this range because typical August sea-breeze patterns and any residual morning stratus suppress temperatures below the 78°F threshold, while clear skies prevent drops into the upper 60s. The tight clustering of market-implied odds around 72–75°F reflects this forecast agreement, with small shifts possible only if afternoon winds weaken or the marine layer thins earlier than expected.