**Marine layer depth, onshore flow, and coastal stratus persistence are the dominant controls on San Francisco’s June 16 maximum temperature.** Official forecasts and recent NWS discussions indicate a typical early-summer pattern, with the marine layer around 1,500 feet keeping western and central districts capped near 68–72 °F even as interior valleys warm. Minor differences among the tightly bunched 68–73 °F bins hinge on whether the stratus burns off by midday, how strongly the onshore gradient holds, and exact wind speeds along the immediate coast. A deeper or more persistent layer favors the lower outcomes; any offshore shift or earlier clearing would push readings toward 72–73 °F. Historical June climatology at KSFO centers near 66–68 °F, so current trader consensus aligns closely with model guidance showing only modest warming above average. Updated NWS and NOAA model runs overnight will be the next key input before resolution.