Recent National Weather Service and ensemble model guidance points to a moderate onshore flow and persistent marine layer moderating temperatures in San Francisco on September 26, with daytime highs most likely reaching 65–68 °F under partly cloudy skies and light west-southwest winds. This pattern, typical for late September, favors the market’s leading 68–69 °F bin while keeping 70 °F-plus outcomes less probable absent a stronger offshore component. Updated model runs from the past 24 hours show little shift in the thermal ridge or low-level moisture, reinforcing trader consensus around the mid-to-upper 60s. The highest temperature will be measured at official downtown or airport stations, where afternoon maxima are expected near or slightly below seasonal normals.