Valid Monday September 21, 2020 through Tuesday September 22, 2020

 

Valid Monday September 21, 2020 through Tuesday September 22, 2020

This advisory is in effect through Tuesday afternoon. South Coast AQMD will issue an update if additional information becomes available.

Three major local wildfires are affecting air quality in the region. A wildfire named the Bobcat Fire is burning north of Azusa, Duarte, Monrovia, and Arcadia in the Angeles National Forest.  As of 2:00 PM on Monday, the burn area was reported at 105,345 acres with 15% containment.  Current information on the Bobcat Fire can be found on the Incident Information System (InciWeb) at https://inciweb.nwcg.gov/incident/7152.

A wildfire named the El Dorado Fire is burning in the San Bernardino Mountains near Yucaipa in San Bernardino County.  As of 1:00 PM on Monday, the burn area was reported at 22,576 acres with 59% containment.  Current information on the El Dorado Fire can be found on InciWeb at https://inciweb.nwcg.gov/incident/7148/.

A wildfire named the Snow Fire is burning in the San Jacinto Wilderness near Cabazon in Riverside County.  As of 7:30 AM on Monday, the burn area was approximately 6,013 acres with 38% containment.  Current information on the Snow Fire can be found on the Riverside County Fire Department’s Incident Information website http://www.rvcfire.org/Pages/default.aspx as well as on InciWeb at https://inciweb.nwcg.gov/incident/7207/.

Past and Current Smoke Impacts

The Bobcat Fire is producing substantial amounts of smoke while the El Dorado and Snow Fires are producing less smoke on Monday morning based on satellite and webcam imagery. Smoke from the Bobcat Fire is being transported towards the north. Smoke from the Eldorado Fire is being transported towards the northeast. Smoke from the Snow Fire is being transported to the north and northeast into the northern portions of Coachella Valley.

All South Coast AQMD continuous PM2.5 monitors recording 24-hour average concentrations were below federal air quality standards on Sunday. Since Sunday afternoon, monitors and low-cost sensors throughout the South Coast AQMD jurisdiction measured Air Quality Index (AQI) levels in the Good to Moderate categories. Only one low-cost sensor in Palm Springs near the Snow Fire recorded Unhealthy for Sensitive Groups and Unhealthy values on Sunday Evening. Visit https://www.aqmd.gov/aqdata to view current air quality conditions.

In any area impacted by smoke:  If you smell smoke or see ash due to a wildfire, limit your exposure by remaining indoors with windows and doors closed or seeking alternate shelter, and avoiding vigorous physical activity. For more tips on protecting yourself during a wildfire, see South Coast AQMD’s Wildfire Smoke & Ash Health & Safety Tips page:  http://www.aqmd.gov/wildfire-health-info-smoke-tips

Forecasted Smoke and Ash Impacts

Areas in direct proximity to the Bobcat, El Dorado, and Snow Fires will experience the highest AQI levels due to smoke impacts.  Smoke and ash impacts will be highly variable in both timing and location through Tuesday.

Los Angeles County

• Monday afternoon: Winds will be from the south and push smoke from the Bobcat Fire to the north into the San Gabriel Mountains and out of the South Coast Air Basin.
• Monday evening through Tuesday morning: Winds will be from north and northeast and push smoke from the Bobcat Fire to the south and southwest. Areas along the I-210 corridor in Glendora, Azusa, Arcadia, Pasadena, Glendale, and Burbank will likely see the highest particulate matter levels. The smoke is likely to remain closer to the ground overnight from the southern extents of the fire.
• Tuesday afternoon: Southerly winds are predicted to move smoke from the Bobcat Fire to the north into the mountains of Los Angeles and out of the South Coast Air Basin.

San Bernardino County

• Monday afternoon: Winds will be from the southwest and push smoke from the El Dorado Fire to the northeast into the San Bernardino Mountains. Heavy smoke is possible in the Big Bear area.
• Monday evening through Tuesday morning: Winds will be from the west and push smoke from the El Dorado Fire to the east into the eastern part of the San Bernardino Mountains. Heavy smoke is possible in cities such as Dessert Hot Springs and Palm Springs. The East San Bernardino Valley could see higher PM2.5 levels from the El Dorado Fire as smoke is likely to remain closer to the ground overnight.  The West San Bernardino Mountains and western San Bernardino Valley could also see an increase in PM2.5 levels overnight due to smoke from the Bobcat Fire.
• Tuesday afternoon: Winds will be from the southwest and push smoke from the El Dorado Fire to the northeast into the San Bernardino Mountains. Heavy smoke is possible in the Big Bear area.

Riverside County

• Monday afternoon: Winds will be from the south and push smoke from the Snow Fire to the north into the Northern Coachella Valley.
• Monday evening through Tuesday morning: Winds will come from the west and northwest. Areas east and southeast of the Snow Fire along the I-10 corridor from Cabazon to Cathedral City will likely see the highest particulate matter levels as smoke is likely to remain closer to the ground overnight.
• Tuesday afternoon: Winds are predicted to shift and come from the southwest at times. This will move smoke from the Snow Fire to the northeast into the Coachella Valley.

Extended Outlook for All Fires: Smoke impacts in the South Coast Air Basin and Coachella Valley will likely continue until fire activity decreases for the Bobcat Fire, El Dorado Fire, and Snow Fire. South Coast Air Quality Management District will continue to provide daily smoke advisory updates until air quality impacts from smoke subside.

In order to avoid increasing PM2.5 levels even further, South Coast AQMD recommends that the public avoid burning wood during periods of poor air quality.

Areas of direct impacts and poor air quality may include portions of Los Angeles, Riverside, and San Bernardino Counties in the South Coast AQMD jurisdiction. Unhealthy or higher AQI levels due to PM2.5 concentrations are possible in areas of direct smoke impacts. Impacts will be highly variable throughout the day, impacting different parts of the region at different times.