SmogRank / Countries / United States / July 2026
Most polluted cities in United States, July 2026
666 cities in United States ranked by their average PM2.5 over the 31 days. Worst: Superior at 49.2 µg/m³, #23 of 2,262 cities in the world. Cleanest: Oro Valley at 0.1. A city needs measurements on 70% of the days to be ranked.
- 1SuperiorWisconsin 49.2
- 2MarquetteMichigan 48.9
- 3DuluthMinnesota 42.3
- 4Royal Oaklow-cost sensorsMichigan 37.9
- 5PerrysburgOhio 37.6
- 6OregonOhio 33.6
- 7Wheatonlow-cost sensorsIllinois 33.1
- 8Port HuronMichigan 32.1
- 9NampaIdaho 32.0
- 10DetroitMichigan 31.8
- 10SouthfieldMichigan 31.8
- 12ToledoOhio 31.6
- 12Green BayWisconsin 31.6
- 14DearbornMichigan 31.4
- 15Lincoln ParkMichigan 31.3
- 16Grand RapidsMichigan 30.9
- 16LansingMichigan 30.9
- 18ElginIllinois 30.8
- 19WyomingMichigan 30.5
- 20AppletonWisconsin 30.1
- 21Bay CityMichigan 29.6
- 21TaylorMichigan 29.6
- 21Oconomowoclow-cost sensorsWisconsin 29.6
- 24JenisonMichigan 29.4
- 24Brookfieldlow-cost sensorsWisconsin 29.4
- 26NorthbrookIllinois 29.3
- 26YpsilantiMichigan 29.3
- 28EastpointeMichigan 28.7
- 29WaukeshaWisconsin 28.1
- 30Elmwood ParkIllinois 27.7
- 31FlintMichigan 27.6
- 32MedinaOhio 27.3
- 33Oak LawnIllinois 27.1
- 34Franklin ParkIllinois 26.9
- 34ClevelandOhio 26.9
- 36SteubenvilleOhio 26.8
- 37BridgeviewIllinois 26.4
- 37KalamazooMichigan 26.4
- 39ZionIllinois 26.2
- 40CantonOhio 25.8
- 41NapervilleIllinois 25.6
- 42South MilwaukeeWisconsin 25.5
- 43DoltonIllinois 25.4
- 44BoiseIdaho 25.0
- 45Evanstonlow-cost sensorsIllinois 24.5
- 45RedfordMichigan 24.5
- 47ChicagoIllinois 24.3
- 48BrookfieldIllinois 24.2
- 48WarrenOhio 24.2
- 50RockfordIllinois 24.0
- 50Shaker HeightsOhio 24.0
- 52Cleveland HeightsOhio 23.9
- 53CaryIllinois 23.8
- 54Des PlainesIllinois 23.6
- 55Calumet CityIllinois 22.8
- 55PittsburghPennsylvania 22.8
- 57PortageIndiana 22.6
- 57AkronOhio 22.6
- 57West MifflinPennsylvania 22.6
- 57WeirtonWest Virginia 22.6
- 61CalexicoCalifornia 22.5
- 62YorkPennsylvania 22.4
- 62HammondIndiana 22.4
- 62WestervilleOhio 22.4
- 65PhiladelphiaPennsylvania 22.2
- 66East ChicagoIndiana 21.6
- 66LimaOhio 21.6
- 68HollandMichigan 21.5
- 69Upper Saint ClairPennsylvania 21.4
- 70Camdenlow-cost sensorsNew Jersey 21.3
- 70WilkinsburgPennsylvania 21.3
- 72AuroraIllinois 21.2
- 72ElkhartIndiana 21.2
- 74South BendIndiana 21.1
- 74Eau ClaireWisconsin 21.1
- 76EriePennsylvania 20.9
- 76LancasterPennsylvania 20.9
- 78HarrisburgPennsylvania 20.8
- 79Fort WayneIndiana 20.6
- 79LebanonPennsylvania 20.6
- 81JohnstownPennsylvania 20.5
- 82ChambersburgPennsylvania 20.4
- 82YoungstownOhio 20.4
- 82CarlislePennsylvania 20.4
- 82MadisonWisconsin 20.4
- 86GaryIndiana 20.1
- 87BuffaloNew York 19.9
- 88State CollegePennsylvania 19.8
- 89HermitagePennsylvania 19.7
- 90ColumbusOhio 19.6
- 90Michigan CityIndiana 19.6
- 90BlaineMinnesota 19.6
- 93McKeesportPennsylvania 19.5
- 93Middletonlow-cost sensorsWisconsin 19.5
- 95GahannaOhio 19.4
- 96PennsaukenNew Jersey 19.3
- 96JolietIllinois 19.3
- 98Abingtonlow-cost sensorsPennsylvania 18.8
- 99BurnsvilleMinnesota 18.6
- 99PendletonOregon 18.6
- 101MinneapolisMinnesota 18.5
- 101Saint CloudMinnesota 18.5
- 103Wake Forestlow-cost sensorsNorth Carolina 18.4
- 103Weirton HeightsWest Virginia 18.4
- 105AltoonaPennsylvania 18.2
- 106Saint PaulMinnesota 18.0
- 107SpringfieldOhio 17.9
- 108South LaurelMaryland 17.7
- 108NorristownPennsylvania 17.7
- 110Saint MichaelMinnesota 17.5
- 111Jurupa ValleyCalifornia 17.4
- 112AshburnVirginia 17.3
- 113WilmingtonDelaware 17.1
- 114LaredoTexas 17.0
- 115BearDelaware 16.9
- 115NewarkDelaware 16.9
- 115ReadingPennsylvania 16.9
- 118WashingtonDistrict of Columbia 16.8
- 118ChesterPennsylvania 16.8
- 118DublinOhio 16.8
- 121DoverDelaware 16.7
- 121MiddletownOhio 16.7
- 121BensalemPennsylvania 16.7
- 124SpringfieldVirginia 16.6
- 124LewistonIdaho 16.6
- 124Twin FallsIdaho 16.6
- 124Walla WallaWashington 16.6
- 128BethlehemPennsylvania 16.5
- 129DaytonOhio 16.3
- 130BaltimoreMaryland 16.2
- 130ShakopeeMinnesota 16.2
- 132EwingNew Jersey 16.1
- 133West FargoNorth Dakota 16.0
- 133FontanaCalifornia 16.0
- 135New BrunswickNew Jersey 15.7
- 136Rose HillVirginia 15.6
- 136GlendoraCalifornia 15.6
- 136RiversideCalifornia 15.6
- 139New York CityNew York 15.5
- 139SpokaneWashington 15.5
- 141MissionTexas 15.4
- 141Great FallsMontana 15.4
- 141Spokane ValleyWashington 15.4
- 144HagerstownMaryland 15.3
- 144PeoriaIllinois 15.3
- 144Apple ValleyMinnesota 15.3
- 147ElizabethNew Jersey 15.1
- 148Coeur d'AleneIdaho 15.0
- 149EdinburgTexas 14.9
- 149TrentonNew Jersey 14.9
- 151Corpus ChristiTexas 14.8
- 151CharlottesvilleVirginia 14.8
- 151WhittierCalifornia 14.8
- 154ElktonMaryland 14.7
- 154Oxon Hill-GlassmanorMaryland 14.7
- 156PainesvilleOhio 14.5
- 157ShreveportLouisiana 14.4
- 157BrownsvilleTexas 14.4
- 157LindenNew Jersey 14.4
- 157PatersonNew Jersey 14.4
- 157ScrantonPennsylvania 14.4
- 157RandolphNew Jersey 14.4
- 163Lexingtonlow-cost sensorsMassachusetts 14.3
- 163HolbrookNew York 14.3
- 165Hunt ValleyMaryland 14.2
- 165ScaggsvilleMaryland 14.2
- 165PleasantvilleNew Jersey 14.2
- 165BaytownTexas 14.2
- 165DallasTexas 14.2
- 170DecaturIllinois 14.1
- 170SewellNew Jersey 14.1
- 170Los AngelesCalifornia 14.1
- 173NorwoodOhio 14.0
- 173MuncieIndiana 14.0
- 175MaconGeorgia 13.9
- 175AustinTexas 13.9
- 177Little RockArkansas 13.8
- 177TulsaOklahoma 13.8
- 177BridgeportConnecticut 13.8
- 180Upper AltonIllinois 13.7
- 180Atlantic CityNew Jersey 13.7
- 180San AntonioTexas 13.7
- 183IndianapolisIndiana 13.6
- 183BayonneNew Jersey 13.6
- 185Des MoinesIowa 13.5
- 185ChampaignIllinois 13.5
- 185Fort LeeNew Jersey 13.5
- 188SpringdaleArkansas 13.4
- 188EdgewoodMaryland 13.4
- 188RockvilleMaryland 13.4
- 188Short PumpVirginia 13.4
- 188Jersey CityNew Jersey 13.4
- 193DanburyConnecticut 13.3
- 193RedmondOregon 13.3
- 193MidwayFlorida 13.3
- 196Toms RiverNew Jersey 13.2
- 196RochesterNew York 13.2
- 196AnaheimCalifornia 13.2
- 199Kendale LakesFlorida 13.1
- 199CincinnatiOhio 13.1
- 199SpartanburgSouth Carolina 13.1
- 199AllentownPennsylvania 13.1
- 199BismarckNorth Dakota 13.1
- 204SpringfieldIllinois 13.0
- 204Kansas CityKansas 13.0
- 204PortsmouthOhio 13.0
- 204OmahaNebraska 13.0
- 204PullmanWashington 13.0
- 209Granite CityIllinois 12.9
- 209Lake ElsinoreCalifornia 12.9
- 211WaterburyConnecticut 12.8
- 211MolineIllinois 12.8
- 213West MemphisArkansas 12.7
- 213HoustonTexas 12.7
- 213Live OakTexas 12.7
- 213HarrisonburgVirginia 12.7
- 213AndersonIndiana 12.7
- 213MankatoMinnesota 12.7
- 213FlagstaffArizona 12.7
- 220RichmondVirginia 12.6
- 220ClintonIowa 12.6
- 220Iowa CityIowa 12.6
- 223HopewellVirginia 12.5
- 223HartfordConnecticut 12.5
- 223RochesterMinnesota 12.5
- 226DavenportIowa 12.4
- 227TopekaKansas 12.3
- 227WichitaKansas 12.3
- 227Cedar RapidsIowa 12.3
- 227SyracuseNew York 12.3
- 231MissoulaMontana 12.2
- 232PasadenaTexas 12.1
- 232ChesapeakeVirginia 12.1
- 232LincolnNebraska 12.1
- 232AlbanyNew York 12.1
- 232ButteMontana 12.1
- 237McAlesterOklahoma 12.0
- 237TexarkanaTexas 12.0
- 237ComptonCalifornia 12.0
- 240New OrleansLouisiana 11.9
- 240Fort WorthTexas 11.9
- 240New HavenConnecticut 11.9
- 243Coconut CreekFlorida 11.8
- 243MooreOklahoma 11.8
- 243Deer ParkTexas 11.8
- 243DentonTexas 11.8
- 243AltamontOregon 11.8
- 248Ponca CityOklahoma 11.7
- 248BartlettTennessee 11.7
- 248New LondonConnecticut 11.7
- 248BloomingtonIllinois 11.7
- 248Eagle PassTexas 11.7
- 248GreeleyColorado 11.7
- 254Roanoke RapidsNorth Carolina 11.6
- 254Mission BendTexas 11.6
- 254SpringfieldMassachusetts 11.6
- 254BurbankCalifornia 11.6
- 258MontgomeryAlabama 11.5
- 258OcalaFlorida 11.5
- 258CorsicanaTexas 11.5
- 258BrocktonMassachusetts 11.5
- 258PittsfieldMassachusetts 11.5
- 258PortlandMaine 11.5
- 258MoscowIdaho 11.5
- 265PrichardAlabama 11.4
- 265VeniceFlorida 11.4
- 265AtlantaGeorgia 11.4
- 265Warner RobinsGeorgia 11.4
- 265East Saint LouisIllinois 11.4
- 265FayettevilleNorth Carolina 11.4
- 265Winston-SalemNorth Carolina 11.4
- 265BeltonTexas 11.4
- 265SaginawTexas 11.4
- 265Fort DodgeIowa 11.4
- 265WaterlooIowa 11.4
- 265Santa ClaritaCalifornia 11.4
- 277Bonita SpringsFlorida 11.3
- 277Ferry PassFlorida 11.3
- 277BloomingtonIndiana 11.3
- 277GalvestonTexas 11.3
- 277Missouri CityTexas 11.3
- 277San MarcosTexas 11.3
- 277RoanokeVirginia 11.3
- 284Pompano BeachFlorida 11.2
- 284Ponte Vedra BeachFlorida 11.2
- 284TallahasseeFlorida 11.2
- 284MasonOhio 11.2
- 284Cedar ParkTexas 11.2
- 284TaylorTexas 11.2
- 284La VistaNebraska 11.2
- 291OlatheKansas 11.1
- 291Columbialow-cost sensorsMissouri 11.1
- 291LebanonOhio 11.1
- 291East HamptonVirginia 11.1
- 295St. LouisMissouri 11.0
- 295FlorenceSouth Carolina 11.0
- 295SalemVirginia 11.0
- 295Mission ViejoCalifornia 11.0
- 299DerbyKansas 10.9
- 299JacksonMississippi 10.9
- 301Deerfield BeachFlorida 10.8
- 301Saint JosephMissouri 10.8
- 301EdmondOklahoma 10.8
- 301PflugervilleTexas 10.8
- 301GreenfieldMassachusetts 10.8
- 306MiamiFlorida 10.7
- 306JacksonTennessee 10.7
- 306College StationTexas 10.7
- 306AnkenyIowa 10.7
- 306San DiegoCalifornia 10.7
- 306HelenaMontana 10.7
- 306Moses LakeWashington 10.7
- 313AshlandKentucky 10.6
- 313LafayetteIndiana 10.6
- 315BirminghamAlabama 10.4
- 315OwensboroKentucky 10.4
- 315Kansas CityMissouri 10.4
- 315LexingtonNorth Carolina 10.4
- 315Saint AndrewsSouth Carolina 10.4
- 315CharlestonWest Virginia 10.4
- 315RutlandVermont 10.4
- 315Chula VistaCalifornia 10.4
- 315Cañon CityColorado 10.4
- 324ValdostaGeorgia 10.3
- 324Fort ThomasKentucky 10.3
- 324MonroeLouisiana 10.3
- 324North CharlestonSouth Carolina 10.3
- 324El PasoTexas 10.3
- 329FairhopeAlabama 10.2
- 329DavieFlorida 10.2
- 329JasperIndiana 10.2
- 329MorrisvilleNorth Carolina 10.2
- 329ConroeTexas 10.2
- 329BostonMassachusetts 10.2
- 329New CityNew York 10.2
- 329CorcoranCalifornia 10.2
- 329BendOregon 10.2
- 338South VinelandNew Jersey 10.1
- 338LowellMassachusetts 10.1
- 338MilfordMassachusetts 10.1
- 338WorcesterMassachusetts 10.1
- 338KeeneNew Hampshire 10.1
- 338HermistonOregon 10.1
- 338Candler-McAfeeGeorgia 10.1
- 345EvansvilleIndiana 10.0
- 345LemayMissouri 10.0
- 345HernandoMississippi 10.0
- 345El CajonCalifornia 10.0
- 345Long BeachCalifornia 10.0
- 345Pasadenalow-cost sensorsCalifornia 10.0
- 345Santa BarbaraCalifornia 10.0
- 345Simi ValleyCalifornia 10.0
- 345Arvadalow-cost sensorsColorado 10.0
- 345ThorntonColorado 10.0
- 345Tri-CitiesWashington 10.0
- 356Delray BeachFlorida 9.9
- 356AthensGeorgia 9.9
- 356CharlotteNorth Carolina 9.9
- 356ClemmonsNorth Carolina 9.9
- 356ChattanoogaTennessee 9.9
- 356Idaho FallsIdaho 9.9
- 362GadsdenAlabama 9.8
- 362ColumbusGeorgia 9.8
- 362LouisvilleKentucky 9.8
- 362ChalmetteLouisiana 9.8
- 362GreensboroNorth Carolina 9.8
- 362GreenvilleNorth Carolina 9.8
- 362Port ArthurTexas 9.8
- 362North ChicopeeMassachusetts 9.8
- 362OceansideCalifornia 9.8
- 371SavannahGeorgia 9.7
- 371GulfportMississippi 9.7
- 371La PorteTexas 9.7
- 371BellevueNebraska 9.7
- 371ClovisCalifornia 9.7
- 376BessemerAlabama 9.6
- 376JeffersonvilleIndiana 9.6
- 376ClaytonNorth Carolina 9.6
- 376Fall RiverMassachusetts 9.6
- 376DerryNew Hampshire 9.6
- 376FillmoreCalifornia 9.6
- 376PowayCalifornia 9.6
- 383HattiesburgMississippi 9.5
- 383LynnMassachusetts 9.5
- 383SheridanWyoming 9.5
- 386TampaFlorida 9.4
- 386Valley StationKentucky 9.4
- 386KennerLouisiana 9.4
- 386SpringfieldMissouri 9.4
- 386MaryvilleTennessee 9.4
- 386Tularelow-cost sensorsCalifornia 9.4
- 386BillingsMontana 9.4
- 386Rapid CitySouth Dakota 9.4
- 386Monroelow-cost sensorsWashington 9.4
- 395SulphurLouisiana 9.3
- 395PascagoulaMississippi 9.3
- 395FraminghamMassachusetts 9.3
- 395White PlainsNew York 9.3
- 395West JordanUtah 9.3
- 400Oak RidgeFlorida 9.2
- 400JeffersontownKentucky 9.2
- 400HaverhillMassachusetts 9.2
- 400Santa Monicalow-cost sensorsCalifornia 9.2
- 400PocatelloIdaho 9.2
- 400AshlandOregon 9.2
- 406AlbanyGeorgia 9.1
- 406LeawoodKansas 9.1
- 406KnoxvilleTennessee 9.1
- 406Colorado SpringsColorado 9.1
- 406OdessaTexas 9.1
- 406Four CornersFlorida 9.1
- 412Saint MatthewsKentucky 9.0
- 412Baton RougeLouisiana 9.0
- 412ArnoldMissouri 9.0
- 412RaymoreMissouri 9.0
- 412QuincyMassachusetts 9.0
- 412TemeculaCalifornia 9.0
- 412VisaliaCalifornia 9.0
- 412MillcreekUtah 9.0
- 420DecaturAlabama 8.9
- 420ValricoFlorida 8.9
- 420West PensacolaFlorida 8.9
- 420AugustaMaine 8.9
- 420PortsmouthNew Hampshire 8.9
- 420IndioCalifornia 8.9
- 420Inglewoodlow-cost sensorsCalifornia 8.9
- 427Fort SmithArkansas 8.8
- 427Palm CityFlorida 8.8
- 427University CityMissouri 8.8
- 427HendersonvilleTennessee 8.8
- 431HueytownAlabama 8.7
- 431Fruit CoveFlorida 8.7
- 431JacksonvilleFlorida 8.7
- 431St. PetersburgFlorida 8.7
- 431WellingtonFlorida 8.7
- 431Winter ParkFlorida 8.7
- 431New AlbanyIndiana 8.7
- 431DyersburgTennessee 8.7
- 431ProvidenceRhode Island 8.7
- 431YumaArizona 8.7
- 431DenverColorado 8.7
- 431LongmontColorado 8.7
- 443HickoryNorth Carolina 8.6
- 443White OakOhio 8.6
- 443NewburghNew York 8.6
- 443PhoenixArizona 8.6
- 443San Luis ObispoCalifornia 8.6
- 443West Valley CityUtah 8.6
- 443SunnysideWashington 8.6
- 450HuntsvilleAlabama 8.5
- 450Lake MaryFlorida 8.5
- 450OrlandoFlorida 8.5
- 450LawrencevilleGeorgia 8.5
- 450WatertownSouth Dakota 8.5
- 450BanningCalifornia 8.5
- 450RichmondCalifornia 8.5
- 450TooeleUtah 8.5
- 458Lexington-FayetteKentucky 8.4
- 458AshevilleNorth Carolina 8.4
- 458RaleighNorth Carolina 8.4
- 458NashvilleTennessee 8.4
- 458Casa GrandeArizona 8.4
- 458HanfordCalifornia 8.4
- 458Santa RosaCalifornia 8.4
- 458Thousand OaksCalifornia 8.4
- 458Spanish ForkUtah 8.4
- 467Daytona BeachFlorida 8.3
- 467BrunswickGeorgia 8.3
- 467GainesvilleGeorgia 8.3
- 467LewistonMaine 8.3
- 467SocorroTexas 8.3
- 467MedfordOregon 8.3
- 467WenatcheeWashington 8.3
- 474BartowFlorida 8.2
- 474GainesvilleFlorida 8.2
- 474MuscatineIowa 8.2
- 474BrookingsSouth Dakota 8.2
- 474BakersfieldCalifornia 8.2
- 474VictorvilleCalifornia 8.2
- 474Fort CollinsColorado 8.2
- 474BozemanMontana 8.2
- 474OremUtah 8.2
- 483LafayetteLouisiana 8.1
- 483FresnoCalifornia 8.1
- 483Torrancelow-cost sensorsCalifornia 8.1
- 483PuebloColorado 8.1
- 483Sunland ParkNew Mexico 8.1
- 483BoulderColorado 8.1
- 483Brigham CityUtah 8.1
- 490Fort MyersFlorida 8.0
- 490Safety HarborFlorida 8.0
- 490LibertyMissouri 8.0
- 490GreenvilleSouth Carolina 8.0
- 490ClarksvilleTennessee 8.0
- 490PortervilleCalifornia 8.0
- 490San JoseCalifornia 8.0
- 490Yuba CityCalifornia 8.0
- 498Belle GladeFlorida 7.9
- 498NicholasvilleKentucky 7.9
- 498KingsportTennessee 7.9
- 498BristolVirginia 7.9
- 498Grand IslandNebraska 7.9
- 498Sioux FallsSouth Dakota 7.9
- 498Arroyo GrandeCalifornia 7.9
- 498MaderaCalifornia 7.9
- 498OrcuttCalifornia 7.9
- 507McDonoughGeorgia 7.8
- 507El CentroCalifornia 7.8
- 507TurlockCalifornia 7.8
- 510SalinasCalifornia 7.7
- 510BountifulUtah 7.7
- 510HerrimanUtah 7.7
- 510North OgdenUtah 7.7
- 514ColumbiaTennessee 7.6
- 514HobbsNew Mexico 7.6
- 516Palm BayFlorida 7.5
- 516ElizabethtownKentucky 7.5
- 516Huntington Beachlow-cost sensorsCalifornia 7.5
- 516Salt Lake CityUtah 7.5
- 520GlendaleArizona 7.4
- 520BrawleyCalifornia 7.4
- 520DavisCalifornia 7.4
- 520MercedCalifornia 7.4
- 520Ken CarylColorado 7.4
- 525SarasotaFlorida 7.3
- 525TempeArizona 7.3
- 525RosevilleCalifornia 7.3
- 525AmarilloTexas 7.3
- 525WindsorColorado 7.3
- 530PaducahKentucky 7.2
- 530CookevilleTennessee 7.2
- 530OxnardCalifornia 7.2
- 533NipomoCalifornia 7.1
- 533San LeandroCalifornia 7.1
- 533LubbockTexas 7.1
- 536East LakeFlorida 7.0
- 536BangorMaine 7.0
- 536BerkeleyCalifornia 7.0
- 536MagnaUtah 7.0
- 540CoventryRhode Island 6.9
- 541MesaArizona 6.7
- 542AberdeenSouth Dakota 6.6
- 542GilroyCalifornia 6.6
- 542Santa CruzCalifornia 6.6
- 545San FranciscoCalifornia 6.5
- 545VallejoCalifornia 6.5
- 547TucsonArizona 6.4
- 547OaklandCalifornia 6.4
- 547StocktonCalifornia 6.4
- 547Spanish SpringsNevada 6.4
- 547EllensburgWashington 6.4
- 552DurhamNorth Carolina 6.3
- 552LaconiaNew Hampshire 6.3
- 554PawtucketRhode Island 6.2
- 554Casas AdobesArizona 6.2
- 554GaltCalifornia 6.2
- 554Cedar CityUtah 6.2
- 558LincolnCalifornia 6.1
- 558Rio RanchoNew Mexico 6.1
- 558BellinghamWashington 6.1
- 558YakimaWashington 6.1
- 562LivermoreCalifornia 6.0
- 562MantecaCalifornia 6.0
- 562Columbia CityWashington 6.0
- 562GilletteWyoming 6.0
- 562Arden-ArcadeCalifornia 6.0
- 567Redwood CityCalifornia 5.9
- 567AlbuquerqueNew Mexico 5.9
- 567Las CrucesNew Mexico 5.9
- 567RenoNevada 5.9
- 567HighlandUtah 5.9
- 572NogalesArizona 5.8
- 572PaysonArizona 5.8
- 572ConcordCalifornia 5.8
- 575RidgecrestCalifornia 5.6
- 576SacramentoCalifornia 5.5
- 576TracyCalifornia 5.5
- 576The DallesOregon 5.5
- 576AuburnWashington 5.5
- 580HollisterCalifornia 5.4
- 580LancasterCalifornia 5.4
- 582ModestoCalifornia 5.3
- 582TruckeeCalifornia 5.3
- 582HurricaneUtah 5.3
- 582TigardOregon 5.3
- 582RentonWashington 5.3
- 582TacomaWashington 5.3
- 588ParadiseCalifornia 5.2
- 588VacavilleCalifornia 5.2
- 588SeattleWashington 5.2
- 588CheyenneWyoming 5.2
- 592MesquiteNevada 5.1
- 593Las VegasNevada 5.0
- 593ReddingCalifornia 5.0
- 593LaramieWyoming 5.0
- 596FolsomCalifornia 4.9
- 596Parkerlow-cost sensorsColorado 4.9
- 596GreshamOregon 4.9
- 599AtascaderoCalifornia 4.8
- 599Encinitaslow-cost sensorsCalifornia 4.8
- 599BremertonWashington 4.8
- 599CasperWyoming 4.8
- 603San RafaelCalifornia 4.7
- 603CanbyOregon 4.7
- 603KentWashington 4.7
- 606LompocCalifornia 4.6
- 606Boulder CityNevada 4.6
- 606HillsboroOregon 4.6
- 609ConwaySouth Carolina 4.5
- 609EnterpriseNevada 4.5
- 609Rock SpringsWyoming 4.5
- 612UkiahCalifornia 4.4
- 612HendersonNevada 4.4
- 612Spring ValleyNevada 4.4
- 612EugeneOregon 4.4
- 612Port AngelesWashington 4.4
- 612ShorelineWashington 4.4
- 618Carson CityNevada 4.3
- 618Loganlow-cost sensorsUtah 4.3
- 618LongviewWashington 4.3
- 618North Creeklow-cost sensorsWashington 4.3
- 618Salmon CreekWashington 4.3
- 623Los Banoslow-cost sensorsCalifornia 4.2
- 623BeavertonOregon 4.2
- 623Summerlin SouthNevada 4.2
- 626MaranaArizona 4.1
- 626Goletalow-cost sensorsCalifornia 4.1
- 626AlbanyOregon 4.1
- 626Grants PassOregon 4.1
- 626CentraliaWashington 4.1
- 631Delanolow-cost sensorsCalifornia 4.0
- 631Oregon CityOregon 4.0
- 631PortlandOregon 4.0
- 631SalemOregon 4.0
- 631AberdeenWashington 4.0
- 631VancouverWashington 4.0
- 637BadgerAlaska 3.9
- 638ChicoCalifornia 3.8
- 638BellevueWashington 3.8
- 638BurienWashington 3.8
- 641Mount VernonWashington 3.7
- 642ParklandWashington 3.6
- 642KīheiHawaii 3.6
- 644Apache JunctionArizona 3.5
- 644WoodburnOregon 3.5
- 644AnacortesWashington 3.5
- 647Union Hill-Novelty Hilllow-cost sensorsWashington 3.4
- 648KahuluiHawaii 3.3
- 648HonoluluHawaii 3.3
- 650MilwaukieOregon 3.2
- 651Green ValleyArizona 3.1
- 651Coos BayOregon 3.1
- 651LaceyWashington 3.1
- 651HiloHawaii 3.1
- 655CorvallisOregon 2.9
- 655RoseburgOregon 2.9
- 657Palo Altolow-cost sensorsCalifornia 2.8
- 657Kirklandlow-cost sensorsWashington 2.8
- 659DallasOregon 2.7
- 659Bothelllow-cost sensorsWashington 2.7
- 659Picnic Point-North LynnwoodWashington 2.7
- 662Forest GroveOregon 2.6
- 663McMinnvilleOregon 2.5
- 664FairbanksAlaska 1.9
- 665AnchorageAlaska 1.8
- 666Oro Valleylow-cost sensorsArizona 0.1
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+