Marine layer persistence and onshore flow from the Pacific are anchoring San Francisco's overnight low near the 58–59°F range for August 24, consistent with National Weather Service guidance showing 57–59°F under mostly cloudy to partly cloudy conditions. A stable pressure pattern featuring eastern Pacific low pressure and a Four Corners high has suppressed both heat intrusions and stronger cooling, keeping temperatures near long-term August norms. Model consensus remains tight, yet small variations in marine layer depth, wind speed, or fog clearance timing can shift the minimum by 1–2°F across observation sites, explaining tight clustering between the 58–59°F and 60–61°F bins. Historical climatology places typical August lows at 55–57°F, so current conditions represent slightly above-average overnight readings with limited downside risk absent an unexpected surge in onshore winds.