Red Flag Warning

...RED FLAG WARNING IN EFFECT THROUGH 3 PM FRIDAY FOR MANY INTERIOR PORTIONS OF SOUTHWEST CALIFORNIA DUE TO EXTREME HEAT AND INSTABILITY ALONG WITH LOCALLY GUSTY WINDS AND LOW HUMIDITIES...

...RED FLAG WARNING IN EFFECT FROM FRIDAY 5 AM THROUGH 3 PM ACROSS ALL OF SAN LUIS OBISPO COUNTY TO DO POTENTIAL FOR DRY LIGHTNING...

.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. Additionally, tropical moisture streaming across our area will bring a 15-25 percent chance of thunderstorms to the region, with a moderate risk for frequent fire starts across San Luis Obispo County due to dry lightning potential.

* TEMPERATURES...Highs 100 to 110 across the lower mountains, adjacent foothills and the Cuyama Valley, and 85 to 95 across higher mountains. Very deep mixing heights of 12,000 to 17,000 feet today, slightly lower on Friday.

* WINDS...Local west to north winds 15 to 25 mph with gusts up to 35 mph at times, strongest across the I-5 and Highway 33 corridors. A slightly stronger northerly wind push is possible late tonight into Friday morning, with gusts up to 40 mph possible across the I-5 corridor and other favored interior mountain passes.

* RELATIVE HUMIDITY...Minimum humidities 12 to 25 percent. 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.