Skip to main content Currently Reading These parts of the S.F. Bay Area will be under a red flag warning this weekend, indicating heightened fire risk FacebookTwitterEmail A National Weather Service map showing the regions impacted by this weekend’s Red Flag Warning, indicating an elevated wildfire risk.Courtesy National Weather Service With dry offshore winds and warm temperatures forecast for the weekend, the National Weather Service has issued a red flag warning — the first of the year and a possible portent of a long and catastrophic fire season. The warning, which cautions that conditions could make it easier for wildfires to spark and spread, begins at 11 p.m. Friday and will last until 6 a.m. on Monday. It covers the North Bay mountains and East Bay hills as well as interior valleys.