SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT DAILY AIR QUALITY FORECAST VALID: SAT., SEP. 19, 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 62 57 0.8 27 12 15 58 2 NW Coastal LA 54 48 0.3 27 10 13 53 3 SW Coastal LA 47 41 0.2 27 9 14 50 4 S Coastal LA 55 52 0.4 27 10 15 53 5 Southeast LA Co 59 56 0.6 30 11 18 55 6 W San Fernando Vly 72 68 0.4 27 10 9 93 7 E San Fernando Vly 72 65 0.6 29 14 14 84 8 W San Gabriel Vly 69 63 0.3 34 15 11 77 9 E San Gabriel Vly 80 71 0.4 39 13 14 101 10 Pomona Walnut Vly 77 67 0.5 39 13 18 90 11 S San Gabriel Vly 64 60 0.3 35 12 18 67 12 S Central LA Co 57 54 0.4 27 11 10 55 13 Santa Clarita Vly 77 70 0.2 30 11 13 100 15 San Gabriel Mts 75 67 0.4 39 13 25 90 Los Angeles County: Mojave Desert Air Basin 14 Antelope Vly 66 61 0.3 35 12 30 71 Orange County: South Coast Air Basin 16 N Orange Co 60 57 0.2 37 11 11 58 17 Central Orange Co 50 47 0.3 27 11 8 55 18 N Coastal Orange Co 45 43 0.3 26 6 13 40 19 Saddleback Vly 50 47 0.2 37 6 10 44 20 Central Coastal 45 43 0.2 25 6 10 40 21 Capistrano Vly 44 43 0.3 25 6 9 40 Riverside County: South Coast Air Basin 22 Norco/Corona 69 62 0.4 49 11 11 74 23 Metro Riverside Co 80 70 0.6 55 14 12 100 24 Perris Vly 69 65 0.4 38 12 18 84 25 Lake Elsinore 66 58 0.3 22 10 9 61 26 Temecula Vly 52 47 0.3 30 9 8 50 27 Anza Vly 58 56 0.2 33 8 8 54 28 Hemet/San Jacinto 64 60 0.3 34 10 20 67 29 Banning 76 66 0.3 32 9 18 87 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 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 67 65 0.2 40 8 8 84 Riverside County: Mojave Desert Air Basin 31 E Riverside Co 55 54 0.2 27 6 7 50 San Bernardino County: South Coast Air Basin 32 NW San Bernardino Vly 85 74 0.5 35 15 19 112 33 SW San Bernardino Vly 75 66 0.5 49 13 18 87 34 C San Bernardino Vly 86 75 0.4 39 13 20 115 35 E San Bernardino Vly 85 76 0.4 40 12 22 118 36 W San Bernardino Mtns 81 72 0.4 35 12 27 105 37 C San Bernardino Mtns 92 76 0.3 37 8 30 118 38 Big Bear Lake 65 61 0.3 35 6 25 71 San Bernardino County: Mojave Desert Air Basin 39 Phelan 66 61 0.3 33 7 37 71 40 Hesperia 73 66 0.3 28 9 37 87 41 Trona 51 47 0.2 19 6 4 44 42 Victorville 72 68 0.3 30 9 40 93 43 Yucca Vly 59 55 0.2 27 6 18 51 44 Barstow 59 53 0.2 27 6 43 49 45 Twentynine Palms 51 49 0.2 27 6 16 45 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- AIR QUALITY FORECAST -------------------------------------------------------------------------------- ON SAT., SEP. 19, 2026, THE SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT PREDICTS THE AIR QUALITY WILL BE ... GOOD in the following area(s): Northern Mojave Desert AQI: 49 Ozone MODERATE in the following area(s): Antelope Valley AQI: 71 Ozone Banning Pass Area AQI: 87 Ozone Big Bear Lake AQI: 71 Ozone Central Mojave Desert AQI: 51 Ozone Coachella Valley/Low Desert AQI: 84 Ozone Coastal Area AQI: 53 PM2.5 Hemet/Elsinore Area AQI: 84 Ozone Inland Orange County AQI: 55 PM2.5 Metropolitan Area AQI: 58 Ozone Riverside Valley AQI: 100 Ozone San Fernando/Santa Clarita Valleys AQI: 100 Ozone San Gabriel Mountains AQI: 90 Ozone Temecula/Anza Area AQI: 54 Ozone Victor Valley AQI: 93 Ozone UNHEALTHY FOR SENSITIVE GROUPS in the following area(s): San Bernardino Mountains AQI: 118 Ozone San Bernardino Valley AQI: 118 Ozone San Gabriel Valley AQI: 101 Ozone ------------------------------------------------------------------------ ------------------------------------------------------------------------ WEATHER FORECAST ------------------------------------------------------------------------ Onshore pressure gradients. Increasing temperature and slightly decreasing ventilation on Saturday. Inversion Base: 2305 FT | Breaking Temperature: 81 DEG F Inversion Breaking: YES | Maximum Mixing HEIGHT: 3215 FT ------------------------------------------------------------------------ ------------------------------------------------------------------------ AIR QUALITY FORECAST RULE IMPLICATIONS ------------------------------------------------------------------------ Area 40 - South Coast Air Basin: MARGINAL-BURN Burning is prohibited in the following source/receptor areas: 9, 32, 34, 35, 36, 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 SATURDAY, SEPTEMBER 19, 2026 IN THE SOUTH COAST AIR BASIN.