SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT DAILY AIR QUALITY FORECAST VALID: SUN., SEP. 13, 2026 -------------------------------------------------------------------------------- SRA AREA 1-HR 8-HR 8-HR 24-HR 24-HR 1-HR MAX NUMBER OZONE OZONE CO PM10 PM2.5 NO2 AQI PPB PPB PPM UG/M3 UG/M3 PPB -------------------------------------------------------------------------------- Los Angeles County: South Coast Air Basin 1 Central LA Co 58 51 0.8 36 13 13 58 2 NW Coastal LA 46 41 0.4 34 10 4 53 3 SW Coastal LA 42 37 0.4 35 8 8 44 4 S Coastal LA 41 38 0.4 39 8 12 44 5 Southeast LA Co 51 46 0.6 40 11 12 55 6 W San Fernando Vly 59 54 0.4 31 10 7 53 7 E San Fernando Vly 67 60 0.6 36 14 10 67 8 W San Gabriel Vly 64 57 0.5 36 14 7 60 9 E San Gabriel Vly 72 66 0.5 31 11 12 87 10 Pomona Walnut Vly 68 60 0.4 38 12 16 67 11 S San Gabriel Vly 57 51 0.4 39 12 12 56 12 S Central LA Co 48 44 0.3 37 9 8 50 13 Santa Clarita Vly 66 66 0.3 31 12 11 87 15 San Gabriel Mts 67 62 0.5 34 12 14 74 Los Angeles County: Mojave Desert Air Basin 14 Antelope Vly 56 49 0.4 27 13 10 58 Orange County: South Coast Air Basin 16 N Orange Co 50 45 0.1 41 11 8 55 17 Central Orange Co 46 42 0.4 41 11 8 55 18 N Coastal Orange Co 43 39 0.3 38 5 10 36 19 Saddleback Vly 52 46 0.3 37 4 8 43 20 Central Coastal 47 42 0.3 32 5 8 39 21 Capistrano Vly 44 40 0.3 30 8 7 44 Riverside County: South Coast Air Basin 22 Norco/Corona 63 59 0.4 38 11 9 64 23 Metro Riverside Co 75 66 0.5 39 14 13 87 24 Perris Vly 59 56 0.4 34 10 17 54 25 Lake Elsinore 50 44 0.3 21 10 6 53 26 Temecula Vly 46 38 0.3 40 11 7 55 27 Anza Vly 49 46 0.2 46 6 8 43 28 Hemet/San Jacinto 54 48 0.4 37 9 18 50 29 Banning 62 54 0.4 35 7 17 50 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- SRA AREA 1-HR 8-HR 8-HR 24-HR 24-HR 1-HR MAX NUMBER OZONE OZONE CO PM10 PM2.5 NO2 AQI PPB PPB PPM UG/M3 UG/M3 PPB -------------------------------------------------------------------------------- Riverside County: Salton Sea Air Basin 30 Coachella Vly 61 54 0.2 59 7 10 53 Riverside County: Mojave Desert Air Basin 31 E Riverside Co 41 39 0.2 37 4 8 36 San Bernardino County: South Coast Air Basin 32 NW San Bernardino Vly 69 64 0.6 35 13 14 80 33 SW San Bernardino Vly 65 61 0.5 38 13 15 71 34 C San Bernardino Vly 74 71 0.5 36 11 19 101 35 E San Bernardino Vly 68 71 0.5 35 10 19 101 36 W San Bernardino Mtns 68 65 0.5 33 10 18 84 37 C San Bernardino Mtns 74 72 0.5 35 7 21 105 38 Big Bear Lake 57 55 0.4 35 5 20 51 San Bernardino County: Mojave Desert Air Basin 39 Phelan 67 61 0.4 29 7 20 71 40 Hesperia 66 59 0.4 28 8 23 64 41 Trona 51 45 0.2 30 4 19 42 42 Victorville 71 63 0.4 29 8 22 77 43 Yucca Vly 56 53 0.3 37 5 16 49 44 Barstow 62 55 0.3 25 6 32 51 45 Twentynine Palms 49 46 0.2 36 6 14 43 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- AIR QUALITY FORECAST -------------------------------------------------------------------------------- ON SUN., SEP. 13, 2026, THE SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT PREDICTS THE AIR QUALITY WILL BE ... GOOD in the following area(s): Banning Pass Area AQI: 50 Ozone Central Mojave Desert AQI: 49 Ozone MODERATE in the following area(s): Antelope Valley AQI: 58 PM2.5 Big Bear Lake AQI: 51 Ozone Coachella Valley/Low Desert AQI: 53 PM10 Coastal Area AQI: 53 PM2.5 Hemet/Elsinore Area AQI: 54 Ozone Inland Orange County AQI: 55 PM2.5 Metropolitan Area AQI: 58 PM2.5 Northern Mojave Desert AQI: 51 Ozone Riverside Valley AQI: 87 Ozone San Fernando/Santa Clarita Valleys AQI: 87 Ozone San Gabriel Mountains AQI: 74 Ozone San Gabriel Valley AQI: 87 Ozone Temecula/Anza Area AQI: 55 PM2.5 Victor Valley AQI: 77 Ozone UNHEALTHY FOR SENSITIVE GROUPS in the following area(s): San Bernardino Mountains AQI: 105 Ozone San Bernardino Valley AQI: 101 Ozone ------------------------------------------------------------------------ ------------------------------------------------------------------------ WEATHER FORECAST ------------------------------------------------------------------------ The remnants of the ridge that brought us the past week's high temperatures will gradually get nudged out by a low pressure system dropping down from the Pacific Northwest. Temperatures will cool 3-5 degrees below Saturday, down to around expected norms. Some morning clouds, especially by the coast, will give way to mostly sunny skies. Westerly (onshore) winds could gust to 25 mph in places. Inversion Base: 2275 FT | Breaking Temperature: 88 DEG F Inversion Breaking: NO | Maximum Mixing HEIGHT: 2700 FT ------------------------------------------------------------------------ ------------------------------------------------------------------------ AIR QUALITY FORECAST RULE IMPLICATIONS ------------------------------------------------------------------------ Area 40 - South Coast Air Basin: MARGINAL-BURN Burning is prohibited in the following source/receptor areas: 34, 35, 37 Area 53 - Mojave Desert Air Basin: BURN Area 55 - Salton Sea Air Basin: BURN Beach Fire Ring Wood Burning: Allowed in All Areas Residential Wood Burning: Allowed in All Areas Coachella Valley Rule 403.1 Wind Forecast: Winds Below 25 MPH ------------------------------------------------------------------------ ATTENTION ALL SCHOOLS AND INDUSTRIES THIS IS THE SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT NO AIR POLLUTION OR HEALTH ADVISIORY EPISODES ARE PREDICTED FOR SUNDAY, SEPTEMBER 13, 2026 IN THE SOUTH COAST AIR BASIN.