RED FLAG WARNING IN EFFECT THROUGH 8 PM PDT THURSDAY FOR THE I-5 CORRIDOR AND THE WESTERN SAN GABRIEL MOUNTAINS INCLUDING THE HIGHWAY 14 CORRIDOR. . RED FLAG WARNING IN EFFECT FROM 3 AM PDT WEDNESDAY THROUGH 8 PM PDT THURSDAY FOR THE INTERIOR MOUNTAINS OF SAN LUIS OBISPO AND SANTA BARBARA COUNTIES INCLUDING THE SANTA LUCIAS AND THE EASTERN SANTA YNEZ RANGE. .A strengthening upper level high pressure system combined with weak offshore flow will bring another heat wave to the region through at least Thursday. The I-5 Corridor was added to the previously issued Red Flag Warning, and the Fire Weather Watch has been upgraded to a Red Flag Warning with the Eastern Santa Ynez Range added. Areas in the Red Flag Warning will have enhanced offshore winds at times during the period overlapping with the hot and very dry conditions, with humidities falling into the single digits. The hot and unstable conditions will bring very high mixing heights (similar to the Bridge Fire event) which will create favorable conditions for large vertical plume growth with any new fires. The National Weather Service in Los Angeles/Oxnard has issued a Red Flag Warning, which is in effect until 8 PM PDT Thursday. * TEMPERATURES. Highs 96 to 106 degrees at lower elevations, with mixing heights peaking at 12,000 to 20,000 feet each afternoon. Minimum temperatures of 72 to 85 degrees will be common. * RELATIVE HUMIDITY. Minimum humidity 5 to 15 percent each day, with very poor overnight recovery of 12 to 25 percent. Poorest Wednesday night. * WINDS. North to northeast winds 10 to 20 mph with gusts 25 to 35 mph. * IMPACTS. If fire ignition occurs, conditions are favorable for large vertical plume growth, rapid fire spread, and extreme fire behavior which would threaten life and property.