Recent National Weather Service and private model runs for San Francisco on October 9 show forecast highs clustered between the mid-60s and low-70s, with peak values sensitive to the strength and timing of onshore southwest flow and marine-layer cloud cover. Persistent Pacific high pressure maintains a moderate temperature regime typical for early October, while subtle differences in wind direction and afternoon clearing account for the spread across 64–76 °F outcomes. The closely bunched market probabilities around 64–71 °F reflect this genuine forecast dispersion, as small shifts in sea-surface temperatures, boundary-layer mixing, or model bias can alter the daily maximum by several degrees before the National Weather Service issues its final observation.