The strong Santa Ana winds tearing through Southern California have fanned multiple brush fires, creating very unhealthy air quality from windblown dust and ash.
Air quality was the worst in the Inland Empire Thursday afternoon, with air in an area centered on Corona considered hazardous, according to the South Coast Air Quality Management District.
The agency issued a dust advisory through Friday afternoon for areas of Riverside, Orange and San Bernardino counties. The areas expected to suffer the worst effects include:
• Riverside County: Corona, Riverside, Norco, Perris Valley, Lake Elsinore, Temecula Valley, Anza Valley, Hemet-San Jacinto Valley, San Gorgonio Pass, Coachella Valley and east Riverside County
• San Bernardino County: western, central and eastern parts of the San Bernardino Valley
• Orange County: northern and central O.C.
The Santa Anas are delivering gusts over 60 mph in some areas, and strong winds over 30 mph are expected to continue throughout Thursday and into Friday morning, officials say.
People who live in areas affected are advised to stay indoors as much as possible, keep windows and doors closed and avoid vigorous physical activity.
The wind event, coupled with low humidity, triggered red flag warnings for much of Los Angeles, Ventura, Orange, San Bernardino and Riverside counties in place through 6 p.m. Friday.
Southern California Edison shut off power for thousands in parts of L.A., Ventura, San Bernardino and Kern counties in an attempt to preempt brush fires sparked by electrical equipment.
Despite the prevention effort, multiple wildfires erupted Thursday.
Two of the largest, the Reche Fire near Moreno Valley and Sandalwood Fire in Calimesa, spread rapidly to several hundred acres, and the latter destroyed several homes. A third blaze burned multiple homes in Fontana.
The wind event is forecast to subside Friday afternoon.
Click here for an interactive map of current air quality conditions.
— South Coast AQMD (@SouthCoastAQMD) October 10, 2019
Here is the forecast of peak wind gusts Thursday. A few isolated spots below Cajon Pass and in the Santa Ana Mountains could have a gust between 60 and 70 MPH, and LA County could have a local gust around 75 MPH in the mountains. #cawx #SantaAnaWinds pic.twitter.com/50RtHc5LZG
— NWS San Diego (@NWSSanDiego) October 9, 2019
Current air quality in the San Gabriel Valley https://t.co/nqIYrRt7LO
— Carter Rubin (@CarterRubin) October 10, 2019
2:44 PM: Doppler radar loop shows smoke plumes from the #RecheFire (near Moreno Valley) and the #SandalwoodFire (near Calimesa). Winds are gusting 20-30 mph from the east-northeast with bone dry air (relative humidity only 5-9%) in place. #CAwx pic.twitter.com/RqsBQd6KAK
— NWS San Diego (@NWSSanDiego) October 10, 2019
Looking closely at this #GOES16 RGB imagery loop, you can see dust (pink colors) blowing from the Ventura/LA County line across the Oxnard Plain and well SW of the Channel Islands. Air quality will be poor due to #SantaAnaWinds! #CAwx #LAwind pic.twitter.com/TrTqZ3iV6b
— NWS Los Angeles (@NWSLosAngeles) October 10, 2019