SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT DAILY AIR QUALITY FORECAST VALID: WED., SEP. 17, 2025 -------------------------------------------------------------------------------- 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 55 0.6 34 16 36 64 2 NW Coastal LA 49 44 0.5 33 12 30 56 3 SW Coastal LA 42 38 0.1 32 14 14 60 4 S Coastal LA 43 40 0.4 30 15 32 62 5 Southeast LA Co 52 47 0.7 32 16 33 64 6 W San Fernando Vly 65 56 0.5 32 12 30 56 7 E San Fernando Vly 54 47 0.6 35 13 34 58 8 W San Gabriel Vly 60 52 0.6 35 16 32 64 9 E San Gabriel Vly 84 75 0.6 29 20 47 115 10 Pomona Walnut Vly 77 68 0.6 39 17 48 93 11 S San Gabriel Vly 52 47 0.6 32 17 32 66 12 S Central LA Co 61 55 0.5 32 17 27 66 13 Santa Clarita Vly 71 56 0.4 35 10 30 54 15 San Gabriel Mts 67 58 0.5 39 14 38 61 Los Angeles County: Mojave Desert Air Basin 14 Antelope Vly 71 61 0.4 41 10 35 71 Orange County: South Coast Air Basin 16 N Orange Co 46 42 0.5 37 14 22 60 17 Central Orange Co 46 42 0.9 21 14 21 60 18 N Coastal Orange Co 47 43 0.5 25 12 29 56 19 Saddleback Vly 59 56 0.3 37 10 31 54 20 Central Coastal 52 50 0.4 26 10 27 53 21 Capistrano Vly 51 48 0.4 29 7 30 44 Riverside County: South Coast Air Basin 22 Norco/Corona 66 61 0.5 53 13 38 71 23 Metro Riverside Co 67 62 0.5 59 15 49 74 24 Perris Vly 62 58 0.4 44 12 40 61 25 Lake Elsinore 61 53 0.4 29 10 31 53 26 Temecula Vly 50 46 0.3 34 10 26 53 27 Anza Vly 50 46 0.3 38 7 22 43 28 Hemet/San Jacinto 55 53 0.4 38 10 32 53 29 Banning 54 52 0.4 34 7 25 48 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 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 62 56 0.2 45 10 18 54 Riverside County: Mojave Desert Air Basin 31 E Riverside Co 45 42 0.2 30 7 14 39 San Bernardino County: South Coast Air Basin 32 NW San Bernardino Vly 63 58 0.5 40 13 33 61 33 SW San Bernardino Vly 66 60 0.7 52 14 43 67 34 C San Bernardino Vly 63 59 0.5 44 12 45 64 35 E San Bernardino Vly 64 61 0.4 47 11 44 71 36 W San Bernardino Mtns 60 57 0.4 39 12 37 58 37 C San Bernardino Mtns 75 72 0.4 42 7 36 105 38 Big Bear Lake 61 55 0.4 38 7 32 51 San Bernardino County: Mojave Desert Air Basin 39 Phelan 56 52 0.4 35 8 32 48 40 Hesperia 65 61 0.4 32 9 35 71 41 Trona 58 56 0.2 29 7 8 54 42 Victorville 63 58 0.4 33 11 31 61 43 Yucca Vly 67 57 0.3 28 7 24 58 44 Barstow 65 61 0.3 30 10 42 71 45 Twentynine Palms 53 47 0.2 29 7 22 44 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- AIR QUALITY FORECAST -------------------------------------------------------------------------------- ON WED., SEP. 17, 2025, THE SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT PREDICTS THE AIR QUALITY WILL BE ... GOOD in the following area(s): Banning Pass Area AQI: 48 Ozone MODERATE in the following area(s): Antelope Valley AQI: 71 Ozone Big Bear Lake AQI: 51 Ozone Central Mojave Desert AQI: 58 Ozone Coachella Valley/Low Desert AQI: 54 Ozone Coastal Area AQI: 62 PM2.5 Hemet/Elsinore Area AQI: 61 Ozone Inland Orange County AQI: 60 PM2.5 Metropolitan Area AQI: 66 PM2.5 Northern Mojave Desert AQI: 71 Ozone Riverside Valley AQI: 74 Ozone San Bernardino Valley AQI: 71 Ozone San Fernando/Santa Clarita Valleys AQI: 58 PM2.5 San Gabriel Mountains AQI: 61 Ozone Temecula/Anza Area AQI: 53 PM2.5 Victor Valley AQI: 71 Ozone UNHEALTHY FOR SENSITIVE GROUPS in the following area(s): San Bernardino Mountains AQI: 105 Ozone San Gabriel Valley AQI: 115 Ozone ------------------------------------------------------------------------ ------------------------------------------------------------------------ WEATHER FORECAST ------------------------------------------------------------------------ Wednesday will be cooler with increasing clouds and higher humidity as tropical moisture moves in. Showers and thunderstorms are likely in the mountains and deserts, with a chance they spread into valleys and coastal areas by evening. Inversion Base: 836 FT | Breaking Temperature: 82 DEG F Inversion Breaking: YES | Maximum Mixing HEIGHT: 1742 FT ------------------------------------------------------------------------ ------------------------------------------------------------------------ AIR QUALITY FORECAST RULE IMPLICATIONS ------------------------------------------------------------------------ Area 40 - South Coast Air Basin: MARGINAL-BURN Burning is prohibited in the following source/receptor areas: 9, 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 WEDNESDAY, SEPTEMBER 17, 2025 IN THE SOUTH COAST AIR BASIN.