Red Flag Warning: Santa Susana Mountains; Eastern San Gabriel Mountains

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Red Flag Warning — Santa Susana Mountains; Eastern San Gabriel Mountains Severity: Severe. Certainty: Likely. ...RED FLAG WARNING IN EFFECT 10 AM TUESDAY TO 3 PM FRIDAY FOR MANY INTERIOR PORTIONS OF SOUTHWEST CALIFORNIA DUE TO EXTREME HEAT AND INSTABILITY ALONG WITH LOCALLY GUSTY WINDS AND LOW HUMIDITIES... .A very hot and unstable air mass combined with locally gusty winds and low humidities will bring a significant risk of large plume dominated fires with rapid spread and extreme fire behavior. The National Weather Service in Los Angeles/Oxnard has issued a Red Flag Warning for extreme heat and instability along with locally gusty winds and low humidities, which is in effect from 10 AM Tuesday to 3 PM PDT Friday. * TEMPERATURES...Highs 96 to 106 across the lower elevations. Highs 85 to 95 common across the higher mountains. Lows in the mid 70s to mid 80s common in the mountains and foothills. * INSTABILITY...Very deep mixing heights of 12,000 to 18,000 feet Tuesday through Thursday, slightly lower on Friday. * WINDS...Southwest 10 to 20 mph with gusts 20 to 30 mph each afternoon into early evening. * RELATIVE HUMIDITY...Minimum humidities 10 to 20 percent each day, Poor recoveries overnight hours in the mountains and foothills with humidities in the 15 to 30 percent range. * IMPACTS...There is a significant risk of large plume dominated fires with rapid fire spread and extreme fire behavior. There is a history of large plume dominated fires this time of year with similar weather and fuel conditions, including the Bridge, Bobcat, and Station fires.