SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT DAILY AIR QUALITY FORECAST VALID: FRI., AUG. 21, 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 61 55 0.5 25 13 26 58 2 NW Coastal LA 57 46 0.3 26 12 14 56 3 SW Coastal LA 50 39 0.1 27 11 14 55 4 S Coastal LA 53 48 0.2 29 10 25 53 5 Southeast LA Co 64 55 0.4 32 12 24 56 6 W San Fernando Vly 69 63 0.3 27 11 18 77 7 E San Fernando Vly 62 57 0.5 28 12 23 58 8 W San Gabriel Vly 78 64 0.5 33 12 21 80 9 E San Gabriel Vly 103 82 0.5 41 12 25 140 10 Pomona Walnut Vly 102 79 0.5 42 13 30 129 11 S San Gabriel Vly 74 61 0.4 36 13 24 71 12 S Central LA Co 52 49 0.3 27 11 16 55 13 Santa Clarita Vly 82 73 0.3 30 12 24 108 15 San Gabriel Mts 75 65 0.4 41 10 29 84 Los Angeles County: Mojave Desert Air Basin 14 Antelope Vly 64 61 0.3 36 13 26 71 Orange County: South Coast Air Basin 16 N Orange Co 77 61 0.2 43 11 15 71 17 Central Orange Co 62 52 0.2 30 11 12 55 18 N Coastal Orange Co 48 44 0.2 32 7 22 41 19 Saddleback Vly 54 47 0.2 43 6 20 44 20 Central Coastal 51 46 0.3 33 7 19 43 21 Capistrano Vly 53 48 0.3 36 7 21 44 Riverside County: South Coast Air Basin 22 Norco/Corona 85 72 0.3 54 12 21 105 23 Metro Riverside Co 101 86 0.4 60 14 22 151 24 Perris Vly 84 77 0.4 44 12 26 122 25 Lake Elsinore 78 68 0.3 36 10 21 93 26 Temecula Vly 55 51 0.3 42 8 19 47 27 Anza Vly 60 55 0.3 47 6 15 51 28 Hemet/San Jacinto 69 65 0.4 42 8 25 84 29 Banning 88 76 0.4 37 7 20 118 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 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 79 68 0.3 54 9 11 93 Riverside County: Mojave Desert Air Basin 31 E Riverside Co 47 46 0.2 38 6 13 43 San Bernardino County: South Coast Air Basin 32 NW San Bernardino Vly 92 75 0.5 39 13 33 115 33 SW San Bernardino Vly 92 74 0.4 54 13 34 112 34 C San Bernardino Vly 99 85 0.4 37 12 38 150 35 E San Bernardino Vly 100 90 0.4 43 11 28 161 36 W San Bernardino Mtns 88 75 0.4 38 9 33 115 37 C San Bernardino Mtns 93 84 0.4 36 7 32 147 38 Big Bear Lake 81 73 0.4 37 7 27 108 San Bernardino County: Mojave Desert Air Basin 39 Phelan 67 63 0.4 35 6 29 77 40 Hesperia 69 64 0.4 29 8 31 80 41 Trona 59 53 0.2 28 7 29 49 42 Victorville 65 64 0.4 32 10 29 80 43 Yucca Vly 73 64 0.3 39 9 21 80 44 Barstow 64 60 0.3 33 10 43 67 45 Twentynine Palms 66 59 0.3 38 6 19 64 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- AIR QUALITY FORECAST -------------------------------------------------------------------------------- ON FRI., AUG. 21, 2026, THE SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT PREDICTS THE AIR QUALITY WILL BE ... MODERATE in the following area(s): Antelope Valley AQI: 71 Ozone Central Mojave Desert AQI: 80 Ozone Coachella Valley/Low Desert AQI: 93 Ozone Coastal Area AQI: 56 PM2.5 Inland Orange County AQI: 55 PM2.5 Metropolitan Area AQI: 71 Ozone Northern Mojave Desert AQI: 67 Ozone San Gabriel Mountains AQI: 84 Ozone Temecula/Anza Area AQI: 51 Ozone Victor Valley AQI: 80 Ozone UNHEALTHY FOR SENSITIVE GROUPS in the following area(s): Banning Pass Area AQI: 118 Ozone Big Bear Lake AQI: 108 Ozone Hemet/Elsinore Area AQI: 122 Ozone San Bernardino Mountains AQI: 147 Ozone San Fernando/Santa Clarita Valleys AQI: 108 Ozone San Gabriel Valley AQI: 140 Ozone UNHEALTHY in the following area(s): Riverside Valley AQI: 151 Ozone San Bernardino Valley AQI: 161 Ozone ------------------------------------------------------------------------ ------------------------------------------------------------------------ WEATHER FORECAST ------------------------------------------------------------------------ Moisture will increase today and Friday with a slight chance of afternoon showers and thunderstorms for the mountains and deserts. High temperatures will remain around 5 degrees above average. Inversion Base: 1589 FT | Breaking Temperature: 91 DEG F Inversion Breaking: NO | Maximum Mixing HEIGHT: 1815 FT ------------------------------------------------------------------------ ------------------------------------------------------------------------ AIR QUALITY FORECAST RULE IMPLICATIONS ------------------------------------------------------------------------ Area 40 - South Coast Air Basin: NO-BURN 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 FRIDAY, AUGUST 21, 2026 IN THE SOUTH COAST AIR BASIN.