SmogRank / Countries / United States / July 2025
Most polluted cities in United States, July 2025
650 cities in United States ranked by their average PM2.5 over the 31 days. Worst: Duluth at 26.6 µg/m³, #57 of 2,283 cities in the world. Cleanest: Atascadero at 1.2. A city needs measurements on 70% of the days to be ranked.
- 1DuluthMinnesota 26.6
- 1SuperiorWisconsin 26.6
- 3MarquetteMichigan 22.2
- 4West FargoNorth Dakota 22.1
- 4Oconomowoclow-cost sensorsWisconsin 22.1
- 6Green BayWisconsin 19.5
- 7MinneapolisMinnesota 19.1
- 7Saint PaulMinnesota 19.1
- 9BurnsvilleMinnesota 18.4
- 10Eau ClaireWisconsin 18.2
- 11MankatoMinnesota 18.1
- 12AppletonWisconsin 17.9
- 13BlaineMinnesota 17.8
- 14Elmwood ParkIllinois 17.7
- 15Franklin ParkIllinois 17.2
- 16MilwaukeeWisconsin 17.0
- 17Saint CloudMinnesota 16.9
- 18ShakopeeMinnesota 16.4
- 19Des PlainesIllinois 16.3
- 19BadgerAlaska 16.3
- 21BridgeviewIllinois 16.1
- 21Saint MichaelMinnesota 16.1
- 23WyomingMichigan 16.0
- 24Wake Forestlow-cost sensorsNorth Carolina 15.9
- 24Apple ValleyMinnesota 15.9
- 26West MemphisArkansas 15.7
- 27DoltonIllinois 15.6
- 27WaukeshaWisconsin 15.6
- 29ChicagoIllinois 15.2
- 29Grand RapidsMichigan 15.2
- 31RochesterMinnesota 15.1
- 32SewellNew Jersey 15.0
- 33FairbanksAlaska 14.9
- 34BrookfieldIllinois 14.5
- 34CaryIllinois 14.5
- 34HammondIndiana 14.5
- 34PortageIndiana 14.5
- 34South MilwaukeeWisconsin 14.5
- 39HoustonTexas 14.4
- 39ElginIllinois 14.4
- 41NapervilleIllinois 14.3
- 41KalamazooMichigan 14.3
- 41RedfordMichigan 14.3
- 44CincinnatiOhio 14.2
- 44Pasadenalow-cost sensorsCalifornia 14.2
- 46ZionIllinois 14.1
- 46Michigan CityIndiana 14.1
- 46Bay CityMichigan 14.1
- 46MadisonWisconsin 14.1
- 50JolietIllinois 14.0
- 51RockfordIllinois 13.9
- 51HollandMichigan 13.9
- 51WarrenOhio 13.9
- 54ConroeTexas 13.7
- 54SteubenvilleOhio 13.7
- 54FontanaCalifornia 13.7
- 57LansingMichigan 13.6
- 58IndianapolisIndiana 13.5
- 58DearbornMichigan 13.5
- 58Port HuronMichigan 13.5
- 58ClevelandOhio 13.5
- 62Oak LawnIllinois 13.3
- 62DetroitMichigan 13.3
- 62JenisonMichigan 13.3
- 65ElkhartIndiana 13.2
- 65SouthfieldMichigan 13.2
- 67AlbanyNew York 13.1
- 68GaryIndiana 13.0
- 69AuroraIllinois 12.9
- 69BuffaloNew York 12.9
- 71DaytonOhio 12.8
- 71BaytownTexas 12.8
- 71PasadenaTexas 12.8
- 71East ChicagoIndiana 12.8
- 75Calumet CityIllinois 12.7
- 76Fort WayneIndiana 12.6
- 76South BendIndiana 12.6
- 76GlendoraCalifornia 12.6
- 79ToledoOhio 12.5
- 79West MifflinPennsylvania 12.5
- 81Lincoln ParkMichigan 12.4
- 81CantonOhio 12.4
- 83PeoriaIllinois 12.3
- 84WashingtonDistrict of Columbia 12.2
- 85SpringdaleArkansas 12.1
- 85FishersIndiana 12.1
- 85LindenNew Jersey 12.1
- 85Jurupa ValleyCalifornia 12.1
- 85Great FallsMontana 12.1
- 90SpringfieldOhio 12.0
- 91ColumbusOhio 11.9
- 91MuncieIndiana 11.9
- 93NorthbrookIllinois 11.8
- 93TaylorMichigan 11.8
- 93MillcreekUtah 11.8
- 96Mission BendTexas 11.7
- 96YpsilantiMichigan 11.7
- 96Los AngelesCalifornia 11.7
- 96RiversideCalifornia 11.7
- 100Corpus ChristiTexas 11.6
- 100Fort DodgeIowa 11.6
- 100YoungstownOhio 11.6
- 103Terre HauteIndiana 11.5
- 103New HavenConnecticut 11.5
- 103BrookingsSouth Dakota 11.5
- 106Columbialow-cost sensorsMissouri 11.4
- 106PennsaukenNew Jersey 11.4
- 106Port ArthurTexas 11.4
- 106ElizabethNew Jersey 11.4
- 106WestervilleOhio 11.4
- 106CalexicoCalifornia 11.4
- 112Little RockArkansas 11.3
- 112JacksonTennessee 11.3
- 112DentonTexas 11.3
- 112La PorteTexas 11.3
- 112Missouri CityTexas 11.3
- 112BurbankCalifornia 11.3
- 112BismarckNorth Dakota 11.3
- 119AustinTexas 11.2
- 119PortlandMaine 11.2
- 119EastpointeMichigan 11.2
- 122LouisvilleKentucky 11.1
- 122DallasTexas 11.1
- 122TexarkanaTexas 11.1
- 122West JordanUtah 11.1
- 126PortsmouthOhio 11.0
- 126Cleveland HeightsOhio 11.0
- 126HartfordConnecticut 11.0
- 126Shaker HeightsOhio 11.0
- 126Eagle PassTexas 11.0
- 131ColumbusIndiana 10.9
- 131EdinburgTexas 10.9
- 131San AntonioTexas 10.9
- 131Des MoinesIowa 10.9
- 131AkronOhio 10.9
- 131PittsburghPennsylvania 10.9
- 131BakersfieldCalifornia 10.9
- 131ReddingCalifornia 10.9
- 139East Saint LouisIllinois 10.8
- 139Saint JosephMissouri 10.8
- 139GalvestonTexas 10.8
- 139ClintonIowa 10.8
- 143Kendale LakesFlorida 10.7
- 143MissionTexas 10.7
- 143WilkinsburgPennsylvania 10.7
- 146BrownsvilleTexas 10.6
- 146CorsicanaTexas 10.6
- 146Fort WorthTexas 10.6
- 146MolineIllinois 10.6
- 146New York CityNew York 10.6
- 146RutlandVermont 10.6
- 152BeltonTexas 10.5
- 153MaconGeorgia 10.4
- 153Upper AltonIllinois 10.4
- 153LafayetteLouisiana 10.4
- 153Live OakTexas 10.4
- 153PittsfieldMassachusetts 10.4
- 153Spanish ForkUtah 10.4
- 159MiamiFlorida 10.3
- 159LafayetteIndiana 10.3
- 159AnaheimCalifornia 10.3
- 159ComptonCalifornia 10.3
- 159Santa Monicalow-cost sensorsCalifornia 10.3
- 164Bonita SpringsFlorida 10.2
- 164Ponte Vedra BeachFlorida 10.2
- 164DanburyConnecticut 10.2
- 164Jersey CityNew Jersey 10.2
- 164RochesterNew York 10.2
- 169SpringfieldMassachusetts 10.1
- 169EwingNew Jersey 10.1
- 169McKeesportPennsylvania 10.1
- 169El PasoTexas 10.1
- 169West Valley CityUtah 10.1
- 174EriePennsylvania 10.0
- 174VisaliaCalifornia 10.0
- 176HomesteadFlorida 9.9
- 176OcalaFlorida 9.9
- 176VeniceFlorida 9.9
- 176GainesvilleGeorgia 9.9
- 176Granite CityIllinois 9.9
- 176St. LouisMissouri 9.9
- 176MedinaOhio 9.9
- 176Sunland ParkNew Mexico 9.9
- 184JacksonMississippi 9.8
- 184AnkenyIowa 9.8
- 184KokomoIndiana 9.8
- 184New BrunswickNew Jersey 9.8
- 184PatersonNew Jersey 9.8
- 184UticaNew York 9.8
- 184DublinOhio 9.8
- 184LebanonPennsylvania 9.8
- 184WeirtonWest Virginia 9.8
- 184Oxon Hill-GlassmanorMaryland 9.8
- 194DoverDelaware 9.7
- 194TulsaOklahoma 9.7
- 194ClarksvilleTennessee 9.7
- 194San MarcosTexas 9.7
- 194AshburnVirginia 9.7
- 194KeeneNew Hampshire 9.7
- 194LimaOhio 9.7
- 194HermitagePennsylvania 9.7
- 194PortervilleCalifornia 9.7
- 203Fort LauderdaleFlorida 9.6
- 203JeffersontownKentucky 9.6
- 203PhiladelphiaPennsylvania 9.6
- 203DyersburgTennessee 9.6
- 203Cedar ParkTexas 9.6
- 203SpringfieldVirginia 9.6
- 203HuntingtonWest Virginia 9.6
- 203Cedar RapidsIowa 9.6
- 203AndersonIndiana 9.6
- 203AugustaMaine 9.6
- 203PainesvilleOhio 9.6
- 203PaysonArizona 9.6
- 203Santa ClaritaCalifornia 9.6
- 203Arvadalow-cost sensorsColorado 9.6
- 217SpringfieldIllinois 9.5
- 217Atlantic CityNew Jersey 9.5
- 217East RidgeTennessee 9.5
- 217College StationTexas 9.5
- 217BrocktonMassachusetts 9.5
- 217BensalemPennsylvania 9.5
- 217ScrantonPennsylvania 9.5
- 217Hawthornelow-cost sensorsCalifornia 9.5
- 217HelenaMontana 9.5
- 217OremUtah 9.5
- 227BirminghamAlabama 9.4
- 227EvansvilleIndiana 9.4
- 227JasperIndiana 9.4
- 227Baton RougeLouisiana 9.4
- 227LexingtonNorth Carolina 9.4
- 227WaterburyConnecticut 9.4
- 227BloomingtonIllinois 9.4
- 227BostonMassachusetts 9.4
- 227LewistonMaine 9.4
- 227TrentonNew Jersey 9.4
- 227HarrisburgPennsylvania 9.4
- 227JohnstownPennsylvania 9.4
- 227Agouralow-cost sensorsCalifornia 9.4
- 240GadsdenAlabama 9.3
- 240EdgewoodMaryland 9.3
- 240ArnoldMissouri 9.3
- 240Roanoke RapidsNorth Carolina 9.3
- 240Toms RiverNew Jersey 9.3
- 240MooreOklahoma 9.3
- 240DavenportIowa 9.3
- 240ChampaignIllinois 9.3
- 240HolbrookNew York 9.3
- 240BridgeportConnecticut 9.3
- 240CorcoranCalifornia 9.3
- 251DecaturIllinois 9.2
- 251JeffersonvilleIndiana 9.2
- 251OwensboroKentucky 9.2
- 251HickoryNorth Carolina 9.2
- 251ProvidenceRhode Island 9.2
- 251Santa BarbaraCalifornia 9.2
- 251Candler-McAfeeGeorgia 9.2
- 251MidwayFlorida 9.2
- 259TallahasseeFlorida 9.1
- 259Valley StationKentucky 9.1
- 259CharlotteNorth Carolina 9.1
- 259South VinelandNew Jersey 9.1
- 259New LondonConnecticut 9.1
- 259GreenfieldMassachusetts 9.1
- 259Fort LeeNew Jersey 9.1
- 259Grand JunctionColorado 9.1
- 267Saint MatthewsKentucky 9.0
- 267Iowa CityIowa 9.0
- 267LancasterPennsylvania 9.0
- 270MontgomeryAlabama 8.9
- 270ColumbusGeorgia 8.9
- 270BloomingtonIndiana 8.9
- 270ElktonMaryland 8.9
- 270ClaytonNorth Carolina 8.9
- 270RaleighNorth Carolina 8.9
- 270PleasantvilleNew Jersey 8.9
- 270SpartanburgSouth Carolina 8.9
- 270North ChicopeeMassachusetts 8.9
- 270CarlislePennsylvania 8.9
- 270NorristownPennsylvania 8.9
- 281FairhopeAlabama 8.8
- 281WilmingtonDelaware 8.8
- 281Palm CityFlorida 8.8
- 281SulphurLouisiana 8.8
- 281Oklahoma CityOklahoma 8.8
- 281DerryNew Hampshire 8.8
- 281PortsmouthNew Hampshire 8.8
- 281SyracuseNew York 8.8
- 281VictorvilleCalifornia 8.8
- 281OdessaTexas 8.8
- 281La Crescenta-Montroselow-cost sensorsCalifornia 8.8
- 281RandolphNew Jersey 8.8
- 293Deerfield BeachFlorida 8.7
- 293Warner RobinsGeorgia 8.7
- 293KennerLouisiana 8.7
- 293New OrleansLouisiana 8.7
- 293LebanonOhio 8.7
- 293HendersonvilleTennessee 8.7
- 293ThorntonColorado 8.7
- 300PaducahKentucky 8.6
- 300HuntsvilleAlabama 8.6
- 300AtlantaGeorgia 8.6
- 300OlatheKansas 8.6
- 300ScaggsvilleMaryland 8.6
- 300LemayMissouri 8.6
- 300LibertyMissouri 8.6
- 300Winston-SalemNorth Carolina 8.6
- 300JenksOklahoma 8.6
- 300ChattanoogaTennessee 8.6
- 300KnoxvilleTennessee 8.6
- 300BangorMaine 8.6
- 300State CollegePennsylvania 8.6
- 300Carsonlow-cost sensorsCalifornia 8.6
- 300ChicoCalifornia 8.6
- 300Long BeachCalifornia 8.6
- 316Kansas CityMissouri 8.5
- 316SpringfieldMissouri 8.5
- 316ClemmonsNorth Carolina 8.5
- 316ChesterPennsylvania 8.5
- 316FlorenceSouth Carolina 8.5
- 316NashvilleTennessee 8.5
- 316Fall RiverMassachusetts 8.5
- 316LowellMassachusetts 8.5
- 316MilfordMassachusetts 8.5
- 316GahannaOhio 8.5
- 316AberdeenSouth Dakota 8.5
- 316MaderaCalifornia 8.5
- 316BountifulUtah 8.5
- 329Delray BeachFlorida 8.4
- 329Oak RidgeFlorida 8.4
- 329Fort ThomasKentucky 8.4
- 329ChalmetteLouisiana 8.4
- 329MorrisvilleNorth Carolina 8.4
- 329White OakOhio 8.4
- 329McAlesterOklahoma 8.4
- 329Ponca CityOklahoma 8.4
- 329MaryvilleTennessee 8.4
- 329Rose HillVirginia 8.4
- 329FraminghamMassachusetts 8.4
- 329LynnMassachusetts 8.4
- 329QuincyMassachusetts 8.4
- 329WoodlandCalifornia 8.4
- 343PrichardAlabama 8.3
- 343Belle GladeFlorida 8.3
- 343Daytona BeachFlorida 8.3
- 343AlbanyGeorgia 8.3
- 343ValdostaGeorgia 8.3
- 343AshlandKentucky 8.3
- 343Lexington-FayetteKentucky 8.3
- 343GreensboroNorth Carolina 8.3
- 343EdmondOklahoma 8.3
- 343LawtonOklahoma 8.3
- 343Saint AndrewsSouth Carolina 8.3
- 343SaginawTexas 8.3
- 343RichmondVirginia 8.3
- 343Sioux FallsSouth Dakota 8.3
- 343WatertownSouth Dakota 8.3
- 343UkiahCalifornia 8.3
- 343Rapid CitySouth Dakota 8.3
- 360EssexMaryland 8.2
- 360HernandoMississippi 8.2
- 360PascagoulaMississippi 8.2
- 360CharlottesvilleVirginia 8.2
- 360ChesapeakeVirginia 8.2
- 360HaverhillMassachusetts 8.2
- 360WorcesterMassachusetts 8.2
- 360IndioCalifornia 8.2
- 360Inglewoodlow-cost sensorsCalifornia 8.2
- 360Torrancelow-cost sensorsCalifornia 8.2
- 360Las CrucesNew Mexico 8.2
- 360Cedar CityUtah 8.2
- 360LongmontColorado 8.2
- 373DecaturAlabama 8.1
- 373BearDelaware 8.1
- 373TopekaKansas 8.1
- 373GulfportMississippi 8.1
- 373FayettevilleNorth Carolina 8.1
- 373KingsportTennessee 8.1
- 373Simi ValleyCalifornia 8.1
- 380NewarkDelaware 8.0
- 380DavieFlorida 8.0
- 380AugustaGeorgia 8.0
- 380New AlbanyIndiana 8.0
- 380BaltimoreMaryland 8.0
- 380GreenvilleNorth Carolina 8.0
- 380MasonOhio 8.0
- 380North CharlestonSouth Carolina 8.0
- 380ColumbiaTennessee 8.0
- 380El CajonCalifornia 8.0
- 390HueytownAlabama 7.9
- 390DerbyKansas 7.9
- 390University CityMissouri 7.9
- 390GreenvilleSouth Carolina 7.9
- 390Short PumpVirginia 7.9
- 390NewburghNew York 7.9
- 390PowayCalifornia 7.9
- 390Salt Lake CityUtah 7.9
- 398ValricoFlorida 7.8
- 398NicholasvilleKentucky 7.8
- 398YorkPennsylvania 7.8
- 398HarrisonburgVirginia 7.8
- 398CharlestonWest Virginia 7.8
- 398White PlainsNew York 7.8
- 398NogalesArizona 7.8
- 398BanningCalifornia 7.8
- 398GreeleyColorado 7.8
- 398BozemanMontana 7.8
- 408WestonFlorida 7.7
- 408LeawoodKansas 7.7
- 408AshevilleNorth Carolina 7.7
- 408PawtucketRhode Island 7.7
- 408San DiegoCalifornia 7.7
- 408HobbsNew Mexico 7.7
- 408SocorroTexas 7.7
- 408BoulderColorado 7.7
- 408BillingsMontana 7.7
- 408Four CornersFlorida 7.7
- 418WellingtonFlorida 7.6
- 418FresnoCalifornia 7.6
- 418Lomitalow-cost sensorsCalifornia 7.6
- 418ParadiseCalifornia 7.6
- 422Fort MyersFlorida 7.5
- 422OrlandoFlorida 7.5
- 422LawrencevilleGeorgia 7.5
- 422ElizabethtownKentucky 7.5
- 422HopewellVirginia 7.5
- 422GlendaleArizona 7.5
- 422Yuba CityCalifornia 7.5
- 422RenoNevada 7.5
- 422HerrimanUtah 7.5
- 422AnacortesWashington 7.5
- 432Fruit CoveFlorida 7.4
- 432St. PetersburgFlorida 7.4
- 432HagerstownMaryland 7.4
- 432WaterlooIowa 7.4
- 432New CityNew York 7.4
- 432Lake ElsinoreCalifornia 7.4
- 432Lakewoodlow-cost sensorsColorado 7.4
- 432MoscowIdaho 7.4
- 432Brigham CityUtah 7.4
- 441TampaFlorida 7.3
- 441SavannahGeorgia 7.3
- 441RaymoreMissouri 7.3
- 441Casa GrandeArizona 7.3
- 441HurricaneUtah 7.3
- 441NampaIdaho 7.3
- 441MagnaUtah 7.3
- 448TrussvilleAlabama 7.2
- 448Coconut CreekFlorida 7.2
- 448JacksonvilleFlorida 7.2
- 448HattiesburgMississippi 7.2
- 448East HamptonVirginia 7.2
- 448RoanokeVirginia 7.2
- 448OmahaNebraska 7.2
- 448BrawleyCalifornia 7.2
- 448LewistonIdaho 7.2
- 448TooeleUtah 7.2
- 458FlagstaffArizona 7.1
- 458YumaArizona 7.1
- 458DenverColorado 7.1
- 458RexburgIdaho 7.1
- 458North OgdenUtah 7.1
- 458Rock SpringsWyoming 7.1
- 464Fort SmithArkansas 7.0
- 464Lake MaryFlorida 7.0
- 464West PensacolaFlorida 7.0
- 464AthensGeorgia 7.0
- 464WindsorColorado 7.0
- 464HighlandUtah 7.0
- 470McDonoughGeorgia 6.9
- 470MesaArizona 6.9
- 470AlbuquerqueNew Mexico 6.9
- 470Fort CollinsColorado 6.9
- 474SarasotaFlorida 6.8
- 474South LaurelMaryland 6.8
- 474CookevilleTennessee 6.8
- 474LaconiaNew Hampshire 6.8
- 474FillmoreCalifornia 6.8
- 474PhoenixArizona 6.8
- 474TucsonArizona 6.8
- 474San JoseCalifornia 6.8
- 474Thousand OaksCalifornia 6.8
- 474Idaho FallsIdaho 6.8
- 484BrunswickGeorgia 6.7
- 484DurhamNorth Carolina 6.7
- 484TempeArizona 6.7
- 484TurlockCalifornia 6.7
- 484PuebloColorado 6.7
- 484LubbockTexas 6.7
- 484BoiseIdaho 6.7
- 484ButteMontana 6.7
- 492GainesvilleFlorida 6.6
- 492ShreveportLouisiana 6.6
- 492MuscatineIowa 6.6
- 492La VistaNebraska 6.6
- 492BerkeleyCalifornia 6.6
- 492OceansideCalifornia 6.6
- 492RosevilleCalifornia 6.6
- 492TruckeeCalifornia 6.6
- 500RockvilleMaryland 6.5
- 500LincolnCalifornia 6.5
- 500StocktonCalifornia 6.5
- 500Picnic Point-North LynnwoodWashington 6.5
- 504Grand IslandNebraska 6.4
- 504Rio RanchoNew Mexico 6.4
- 504MeridianIdaho 6.4
- 504AltamontOregon 6.4
- 504Summerlin SouthNevada 6.4
- 509Safety HarborFlorida 6.3
- 509BellevueNebraska 6.3
- 509MercedCalifornia 6.3
- 509Apache JunctionArizona 6.3
- 509SunnysideWashington 6.3
- 514DavisCalifornia 6.2
- 514FolsomCalifornia 6.2
- 514TemeculaCalifornia 6.2
- 514Cañon CityColorado 6.2
- 518Palm BayFlorida 6.1
- 518LincolnNebraska 6.1
- 518OxnardCalifornia 6.1
- 518Las VegasNevada 6.1
- 522Columbia CityWashington 6.0
- 522CasperWyoming 6.0
- 524Winter ParkFlorida 5.9
- 524ClovisCalifornia 5.9
- 524Florinlow-cost sensorsCalifornia 5.9
- 524Ken CarylColorado 5.9
- 524EnterpriseNevada 5.9
- 524Spanish SpringsNevada 5.9
- 524Coeur d'AleneIdaho 5.9
- 524SeattleWashington 5.9
- 532GaltCalifornia 5.8
- 532RidgecrestCalifornia 5.8
- 532TracyCalifornia 5.8
- 532Arden-ArcadeCalifornia 5.8
- 536ConwaySouth Carolina 5.7
- 536Casas AdobesArizona 5.7
- 536El CentroCalifornia 5.7
- 536LancasterCalifornia 5.7
- 536MedfordOregon 5.7
- 541East LakeFlorida 5.6
- 541Goletalow-cost sensorsCalifornia 5.6
- 541CondaIdaho 5.6
- 541PocatelloIdaho 5.6
- 541SpokaneWashington 5.6
- 541Spokane ValleyWashington 5.6
- 541SheridanWyoming 5.6
- 548ModestoCalifornia 5.5
- 548RichmondCalifornia 5.5
- 548HendersonNevada 5.5
- 548Spring ValleyNevada 5.5
- 548RedmondOregon 5.5
- 553CoventryRhode Island 5.4
- 554AuburnWashington 5.3
- 554GilletteWyoming 5.3
- 556Moses LakeWashington 5.2
- 556Walla WallaWashington 5.2
- 556LaramieWyoming 5.2
- 559VallejoCalifornia 5.1
- 559Carson CityNevada 5.1
- 561Hunt ValleyMaryland 5.0
- 561Green ValleyArizona 5.0
- 561Windsorlow-cost sensorsCalifornia 5.0
- 561Dodge CityKansas 5.0
- 561AshlandOregon 5.0
- 561BendOregon 5.0
- 561BellinghamWashington 5.0
- 568PleasantonCalifornia 4.9
- 568TacomaWashington 4.9
- 570MantecaCalifornia 4.8
- 570San LeandroCalifornia 4.8
- 570MesquiteNevada 4.8
- 570Twin FallsIdaho 4.8
- 570PullmanWashington 4.8
- 575MaranaArizona 4.7
- 575PendletonOregon 4.7
- 577OaklandCalifornia 4.6
- 577Palo Altolow-cost sensorsCalifornia 4.6
- 577BremertonWashington 4.6
- 580San Luis ObispoCalifornia 4.5
- 580Boulder CityNevada 4.5
- 580ShorelineWashington 4.5
- 583GilroyCalifornia 4.4
- 583EugeneOregon 4.4
- 583WenatcheeWashington 4.4
- 586HermistonOregon 4.3
- 586RentonWashington 4.3
- 586YakimaWashington 4.3
- 589MartinezCalifornia 4.2
- 589LittletonColorado 4.2
- 589TigardOregon 4.2
- 589BellevueWashington 4.2
- 593SacramentoCalifornia 4.1
- 593South San Franciscolow-cost sensorsCalifornia 4.1
- 593MissoulaMontana 4.1
- 593CheyenneWyoming 4.1
- 597AberdeenWashington 4.0
- 597Port AngelesWashington 4.0
- 599HollisterCalifornia 3.9
- 599SalinasCalifornia 3.9
- 599HillsboroOregon 3.9
- 599The DallesOregon 3.9
- 599EllensburgWashington 3.9
- 599Tri-CitiesWashington 3.9
- 605ConcordCalifornia 3.8
- 606LompocCalifornia 3.7
- 606NipomoCalifornia 3.7
- 606CanbyOregon 3.7
- 609San FranciscoCalifornia 3.6
- 609LongviewWashington 3.6
- 609KīheiHawaii 3.6
- 612Arroyo GrandeCalifornia 3.5
- 612BurienWashington 3.5
- 614VacavilleCalifornia 3.4
- 614PortlandOregon 3.4
- 614SalemOregon 3.4
- 614CentraliaWashington 3.4
- 614KahuluiHawaii 3.4
- 614HonoluluHawaii 3.4
- 614Inglewood-Finn Hilllow-cost sensorsWashington 3.4
- 614Makakilo / Kapolei / Honokai HaleHawaii 3.4
- 622Grants PassOregon 3.3
- 622ParklandWashington 3.3
- 622Salmon CreekWashington 3.3
- 625Redwood CityCalifornia 3.2
- 625BeavertonOregon 3.2
- 625MilwaukieOregon 3.2
- 628San RafaelCalifornia 3.1
- 628Oregon CityOregon 3.1
- 630RoseburgOregon 3.0
- 630VancouverWashington 3.0
- 630HiloHawaii 3.0
- 633LivermoreCalifornia 2.9
- 633Santa CruzCalifornia 2.9
- 633AlbanyOregon 2.9
- 633LaceyWashington 2.9
- 633MarysvilleWashington 2.9
- 638Coos BayOregon 2.8
- 638CorvallisOregon 2.8
- 638DallasOregon 2.8
- 641GreshamOregon 2.7
- 641WoodburnOregon 2.7
- 643McMinnvilleOregon 2.6
- 643Oak HarborWashington 2.6
- 645Mount VernonWashington 2.5
- 646OrcuttCalifornia 2.3
- 646Forest GroveOregon 2.3
- 646AnchorageAlaska 2.3
- 649Santa RosaCalifornia 1.8
- 650AtascaderoCalifornia 1.2
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+