Trader sentiment for San Francisco's March 25 high temperature splits evenly between 68-69°F and 70°F or higher at 17% each, reflecting divergent ensemble forecasts from NOAA's GFS and ECMWF models amid persistent model spread. GFS leans toward mid-50s persistence from a strengthening marine layer fueled by cool coastal sea surface temperatures near 55°F and onshore flow, capping highs via advection fog, while ECMWF favors upper-60s warmth from emerging high-pressure ridging and lighter winds promoting clearer skies. Historical March averages hover at 62°F, but recent 00Z runs showing 500 mb height rises have edged odds toward record-challenging warmth, though SF's microclimate introduces resolution risk near key thresholds.