SmogRank / Countries / United States / May 2026
Most polluted cities in United States, May 2026
659 cities in United States ranked by their average PM2.5 over the 31 days. Worst: Calexico at 27.1 µg/m³, #124 of 2,243 cities in the world. Cleanest: Oro Valley at 0.0. A city needs measurements on 70% of the days to be ranked.
- 1CalexicoCalifornia 27.1
- 2Jurupa ValleyCalifornia 15.0
- 3RiversideCalifornia 13.6
- 4LaredoTexas 12.7
- 5WhittierCalifornia 12.2
- 6EdinburgTexas 12.0
- 6MissionTexas 12.0
- 8ShreveportLouisiana 11.7
- 9Pasadenalow-cost sensorsCalifornia 11.6
- 9Redmondlow-cost sensorsWashington 11.6
- 11Los AngelesCalifornia 11.4
- 12ComptonCalifornia 11.1
- 13Wake Forestlow-cost sensorsNorth Carolina 11.0
- 13FontanaCalifornia 11.0
- 15Santa Monicalow-cost sensorsCalifornia 10.8
- 16Eagle PassTexas 10.5
- 17BaytownTexas 10.3
- 17BrownsvilleTexas 10.3
- 19San DiegoCalifornia 10.2
- 20Corpus ChristiTexas 10.1
- 20AnaheimCalifornia 10.1
- 22El CajonCalifornia 10.0
- 23ChattanoogaTennessee 9.9
- 23DallasTexas 9.9
- 23BurbankCalifornia 9.9
- 23Long BeachCalifornia 9.9
- 27AustinTexas 9.7
- 27WyomingMichigan 9.7
- 27Mission ViejoCalifornia 9.7
- 30VisaliaCalifornia 9.6
- 31PhiladelphiaPennsylvania 9.5
- 31HoustonTexas 9.5
- 31PowayCalifornia 9.5
- 31Torrancelow-cost sensorsCalifornia 9.5
- 35MaconGeorgia 9.3
- 35Chula VistaCalifornia 9.3
- 35San Luis ObispoCalifornia 9.3
- 38Lake ElsinoreCalifornia 9.2
- 38El PasoTexas 9.2
- 40PasadenaTexas 9.1
- 40Simi ValleyCalifornia 9.1
- 42Little RockArkansas 9.0
- 42Santa ClaritaCalifornia 9.0
- 44Deer ParkTexas 8.9
- 44GlendoraCalifornia 8.9
- 44Huntington Beachlow-cost sensorsCalifornia 8.9
- 44NipomoCalifornia 8.9
- 48SpartanburgSouth Carolina 8.8
- 48CorsicanaTexas 8.8
- 48San AntonioTexas 8.8
- 48OaklandCalifornia 8.8
- 48OceansideCalifornia 8.8
- 53PortsmouthOhio 8.7
- 53CorcoranCalifornia 8.7
- 53MantecaCalifornia 8.7
- 53SocorroTexas 8.7
- 57FayettevilleNorth Carolina 8.6
- 57BensalemPennsylvania 8.6
- 57BakersfieldCalifornia 8.6
- 60GainesvilleFlorida 8.5
- 60OwensboroKentucky 8.5
- 60IndioCalifornia 8.5
- 63St. LouisMissouri 8.4
- 63BrookingsSouth Dakota 8.4
- 63Santa BarbaraCalifornia 8.4
- 66Ponte Vedra BeachFlorida 8.3
- 66Live OakTexas 8.3
- 66El CentroCalifornia 8.3
- 69West MemphisArkansas 8.2
- 69JacksonvilleFlorida 8.2
- 69OcalaFlorida 8.2
- 69MooreOklahoma 8.2
- 69WaterlooIowa 8.2
- 69BanningCalifornia 8.2
- 75Fort WorthTexas 8.1
- 75La PorteTexas 8.1
- 75Mission BendTexas 8.1
- 75ClovisCalifornia 8.1
- 75SalinasCalifornia 8.1
- 80Arroyo GrandeCalifornia 8.0
- 81Kendale LakesFlorida 7.9
- 81TallahasseeFlorida 7.9
- 81TexarkanaTexas 7.9
- 81PeoriaIllinois 7.9
- 85Granite CityIllinois 7.8
- 85IndianapolisIndiana 7.8
- 85GalvestonTexas 7.8
- 85Great FallsMontana 7.8
- 89WichitaKansas 7.7
- 89DentonTexas 7.7
- 89Missouri CityTexas 7.7
- 89DoltonIllinois 7.7
- 89TemeculaCalifornia 7.7
- 89MillcreekUtah 7.7
- 95MorrisvilleNorth Carolina 7.6
- 95FlorenceSouth Carolina 7.6
- 95FillmoreCalifornia 7.6
- 95MaderaCalifornia 7.6
- 95PortervilleCalifornia 7.6
- 100AugustaGeorgia 7.5
- 100MiddletownOhio 7.5
- 100TulsaOklahoma 7.5
- 100AnkenyIowa 7.5
- 100West FargoNorth Dakota 7.5
- 100FresnoCalifornia 7.5
- 100MercedCalifornia 7.5
- 100OdessaTexas 7.5
- 108Saint JosephMissouri 7.4
- 108University CityMissouri 7.4
- 108LexingtonNorth Carolina 7.4
- 108ConroeTexas 7.4
- 108Port ArthurTexas 7.4
- 108CharlottesvilleVirginia 7.4
- 108CharlestonWest Virginia 7.4
- 108YumaArizona 7.4
- 108San FranciscoCalifornia 7.4
- 108MidwayFlorida 7.4
- 118SpringdaleArkansas 7.3
- 118VeniceFlorida 7.3
- 118YorkPennsylvania 7.3
- 118College StationTexas 7.3
- 118SaginawTexas 7.3
- 118Fort DodgeIowa 7.3
- 118BridgeviewIllinois 7.3
- 125BrunswickGeorgia 7.2
- 125ValdostaGeorgia 7.2
- 125Warner RobinsGeorgia 7.2
- 125North CharlestonSouth Carolina 7.2
- 125Delanolow-cost sensorsCalifornia 7.2
- 130Bonita SpringsFlorida 7.1
- 130MonroeLouisiana 7.1
- 130New OrleansLouisiana 7.1
- 130CharlotteNorth Carolina 7.1
- 130EdmondOklahoma 7.1
- 130GreenvilleSouth Carolina 7.1
- 130VictorvilleCalifornia 7.1
- 137Oak RidgeFlorida 7.0
- 137Palm CityFlorida 7.0
- 137AtlantaGeorgia 7.0
- 137AshlandKentucky 7.0
- 137Winston-SalemNorth Carolina 7.0
- 137San MarcosTexas 7.0
- 137WatertownSouth Dakota 7.0
- 137HanfordCalifornia 7.0
- 137San JoseCalifornia 7.0
- 146SulphurLouisiana 6.9
- 146MaryvilleTennessee 6.9
- 146BrookfieldIllinois 6.9
- 146HammondIndiana 6.9
- 146New York CityNew York 6.9
- 146NogalesArizona 6.9
- 146PhoenixArizona 6.9
- 146LancasterCalifornia 6.9
- 146Candler-McAfeeGeorgia 6.9
- 155MontgomeryAlabama 6.8
- 155LemayMissouri 6.8
- 155ClaytonNorth Carolina 6.8
- 155HickoryNorth Carolina 6.8
- 155South VinelandNew Jersey 6.8
- 155LawtonOklahoma 6.8
- 155Oklahoma CityOklahoma 6.8
- 155Ponca CityOklahoma 6.8
- 155HendersonvilleTennessee 6.8
- 155Cedar ParkTexas 6.8
- 155TaylorTexas 6.8
- 155Des MoinesIowa 6.8
- 155ReadingPennsylvania 6.8
- 155AtascaderoCalifornia 6.8
- 155OxnardCalifornia 6.8
- 155South Lake TahoeCalifornia 6.8
- 171Fruit CoveFlorida 6.7
- 171AthensGeorgia 6.7
- 171GreenvilleNorth Carolina 6.7
- 171RaleighNorth Carolina 6.7
- 171BeltonTexas 6.7
- 171Calumet CityIllinois 6.7
- 171ElginIllinois 6.7
- 178St. PetersburgFlorida 6.6
- 178ValricoFlorida 6.6
- 178GainesvilleGeorgia 6.6
- 178East Saint LouisIllinois 6.6
- 178Upper AltonIllinois 6.6
- 178Kansas CityKansas 6.6
- 178LouisvilleKentucky 6.6
- 178JacksonMississippi 6.6
- 178NorwoodOhio 6.6
- 178JenksOklahoma 6.6
- 178Saint AndrewsSouth Carolina 6.6
- 178BartlettTennessee 6.6
- 178KnoxvilleTennessee 6.6
- 178BristolVirginia 6.6
- 178Franklin ParkIllinois 6.6
- 178OregonOhio 6.6
- 178SteubenvilleOhio 6.6
- 178LancasterPennsylvania 6.6
- 178West MifflinPennsylvania 6.6
- 178Santa CruzCalifornia 6.6
- 178Sunland ParkNew Mexico 6.6
- 199DecaturAlabama 6.5
- 199TampaFlorida 6.5
- 199EvansvilleIndiana 6.5
- 199Atlantic CityNew Jersey 6.5
- 199PennsaukenNew Jersey 6.5
- 199PleasantvilleNew Jersey 6.5
- 199JacksonTennessee 6.5
- 199PflugervilleTexas 6.5
- 199Elmwood ParkIllinois 6.5
- 199ElizabethNew Jersey 6.5
- 199EwingNew Jersey 6.5
- 199PatersonNew Jersey 6.5
- 199WestervilleOhio 6.5
- 199San LeandroCalifornia 6.5
- 199WoodlandCalifornia 6.5
- 214OrlandoFlorida 6.4
- 214AlbanyGeorgia 6.4
- 214Baton RougeLouisiana 6.4
- 214ClemmonsNorth Carolina 6.4
- 214GreensboroNorth Carolina 6.4
- 214ChesapeakeVirginia 6.4
- 214MuscatineIowa 6.4
- 214Fort WayneIndiana 6.4
- 214FlintMichigan 6.4
- 214RedfordMichigan 6.4
- 214Jersey CityNew Jersey 6.4
- 214ToledoOhio 6.4
- 214LebanonPennsylvania 6.4
- 214BridgeportConnecticut 6.4
- 214Thousand OaksCalifornia 6.4
- 214LewistonIdaho 6.4
- 214West JordanUtah 6.4
- 214Columbia CityWashington 6.4
- 214Four CornersFlorida 6.4
- 233BirminghamAlabama 6.3
- 233WashingtonDistrict of Columbia 6.3
- 233WilmingtonDelaware 6.3
- 233Daytona BeachFlorida 6.3
- 233SavannahGeorgia 6.3
- 233DerbyKansas 6.3
- 233HattiesburgMississippi 6.3
- 233ElkhartIndiana 6.3
- 233Royal Oaklow-cost sensorsMichigan 6.3
- 233ClevelandOhio 6.3
- 233Dodge CityKansas 6.3
- 244HuntsvilleAlabama 6.2
- 244Ferry PassFlorida 6.2
- 244JeffersonvilleIndiana 6.2
- 244TopekaKansas 6.2
- 244Valley StationKentucky 6.2
- 244EssexMaryland 6.2
- 244AshevilleNorth Carolina 6.2
- 244ChicagoIllinois 6.2
- 244OmahaNebraska 6.2
- 244MilwaukeeWisconsin 6.2
- 254BearDelaware 6.1
- 254Fort MyersFlorida 6.1
- 254MiamiFlorida 6.1
- 254DecaturIllinois 6.1
- 254ChalmetteLouisiana 6.1
- 254ScaggsvilleMaryland 6.1
- 254Toms RiverNew Jersey 6.1
- 254ColumbusOhio 6.1
- 254East ChicagoIndiana 6.1
- 254DetroitMichigan 6.1
- 254PerrysburgOhio 6.1
- 254Brigham CityUtah 6.1
- 266Pompano BeachFlorida 6.0
- 266SarasotaFlorida 6.0
- 266LawrencevilleGeorgia 6.0
- 266JasperIndiana 6.0
- 266ArnoldMissouri 6.0
- 266Roanoke RapidsNorth Carolina 6.0
- 266SpringfieldOhio 6.0
- 266McAlesterOklahoma 6.0
- 266HopewellVirginia 6.0
- 266SpringfieldVirginia 6.0
- 266ClintonIowa 6.0
- 266Iowa CityIowa 6.0
- 266BrocktonMassachusetts 6.0
- 266MankatoMinnesota 6.0
- 266HarrisburgPennsylvania 6.0
- 266TurlockCalifornia 6.0
- 266HobbsNew Mexico 6.0
- 283BessemerAlabama 5.9
- 283Delray BeachFlorida 5.9
- 283Safety HarborFlorida 5.9
- 283GulfportMississippi 5.9
- 283HernandoMississippi 5.9
- 283ClarksvilleTennessee 5.9
- 283Rose HillVirginia 5.9
- 283AuroraIllinois 5.9
- 283RockfordIllinois 5.9
- 283LafayetteIndiana 5.9
- 283KalamazooMichigan 5.9
- 283Lincoln ParkMichigan 5.9
- 283New BrunswickNew Jersey 5.9
- 283CantonOhio 5.9
- 283LimaOhio 5.9
- 283GilroyCalifornia 5.9
- 283Cedar CityUtah 5.9
- 283SeattleWashington 5.9
- 301PaducahKentucky 5.8
- 301Lake MaryFlorida 5.8
- 301ColumbusGeorgia 5.8
- 301SpringfieldIllinois 5.8
- 301BaltimoreMaryland 5.8
- 301Columbialow-cost sensorsMissouri 5.8
- 301SpringfieldMissouri 5.8
- 301DaytonOhio 5.8
- 301DyersburgTennessee 5.8
- 301RichmondVirginia 5.8
- 301Oak LawnIllinois 5.8
- 301Bay CityMichigan 5.8
- 301DearbornMichigan 5.8
- 301Grand RapidsMichigan 5.8
- 301LincolnNebraska 5.8
- 301Fort LeeNew Jersey 5.8
- 301HolbrookNew York 5.8
- 301Casa GrandeArizona 5.8
- 301TucsonArizona 5.8
- 301DavisCalifornia 5.8
- 321OlatheKansas 5.7
- 321KennerLouisiana 5.7
- 321PascagoulaMississippi 5.7
- 321CincinnatiOhio 5.7
- 321Short PumpVirginia 5.7
- 321Cedar RapidsIowa 5.7
- 321DavenportIowa 5.7
- 321JolietIllinois 5.7
- 321NapervilleIllinois 5.7
- 321San RafaelCalifornia 5.7
- 321OremUtah 5.7
- 321Spanish ForkUtah 5.7
- 321BellinghamWashington 5.7
- 334TrussvilleAlabama 5.6
- 334Deerfield BeachFlorida 5.6
- 334BloomingtonIndiana 5.6
- 334SewellNew Jersey 5.6
- 334East HamptonVirginia 5.6
- 334PortageIndiana 5.6
- 334PortlandMaine 5.6
- 334NorristownPennsylvania 5.6
- 334ScrantonPennsylvania 5.6
- 334WaukeshaWisconsin 5.6
- 334TempeArizona 5.6
- 334RidgecrestCalifornia 5.6
- 334Santa RosaCalifornia 5.6
- 334HurricaneUtah 5.6
- 334Coeur d'AleneIdaho 5.6
- 334TooeleUtah 5.6
- 334Picnic Point-North LynnwoodWashington 5.6
- 351PrichardAlabama 5.5
- 351Palm BayFlorida 5.5
- 351DurhamNorth Carolina 5.5
- 351ColumbiaTennessee 5.5
- 351KingsportTennessee 5.5
- 351South BendIndiana 5.5
- 351RochesterMinnesota 5.5
- 351CarlislePennsylvania 5.5
- 351South MilwaukeeWisconsin 5.5
- 351Yuba CityCalifornia 5.5
- 351BountifulUtah 5.5
- 351West Valley CityUtah 5.5
- 363NewarkDelaware 5.4
- 363East LakeFlorida 5.4
- 363NicholasvilleKentucky 5.4
- 363Saint MatthewsKentucky 5.4
- 363ElktonMaryland 5.4
- 363Kansas CityMissouri 5.4
- 363DanburyConnecticut 5.4
- 363HartfordConnecticut 5.4
- 363New LondonConnecticut 5.4
- 363WaterburyConnecticut 5.4
- 363Michigan CityIndiana 5.4
- 363TrentonNew Jersey 5.4
- 363WarrenOhio 5.4
- 363Salt Lake CityUtah 5.4
- 377DavieFlorida 5.3
- 377WellingtonFlorida 5.3
- 377West PensacolaFlorida 5.3
- 377New HavenConnecticut 5.3
- 377ChampaignIllinois 5.3
- 377MolineIllinois 5.3
- 377MuncieIndiana 5.3
- 377SpringfieldMassachusetts 5.3
- 377JenisonMichigan 5.3
- 377BellevueNebraska 5.3
- 377HollisterCalifornia 5.3
- 377Rio RanchoNew Mexico 5.3
- 377HerrimanUtah 5.3
- 390New AlbanyIndiana 5.2
- 390ElizabethtownKentucky 5.2
- 390JeffersontownKentucky 5.2
- 390ChesterPennsylvania 5.2
- 390AshburnVirginia 5.2
- 390HarrisonburgVirginia 5.2
- 390RoanokeVirginia 5.2
- 390SalemVirginia 5.2
- 390Cleveland HeightsOhio 5.2
- 390CaryIllinois 5.2
- 390BostonMassachusetts 5.2
- 390AkronOhio 5.2
- 390AllentownPennsylvania 5.2
- 390PittsburghPennsylvania 5.2
- 390WilkinsburgPennsylvania 5.2
- 390SuperiorWisconsin 5.2
- 390Casas AdobesArizona 5.2
- 390GlendaleArizona 5.2
- 390Encinitaslow-cost sensorsCalifornia 5.2
- 390PleasantonCalifornia 5.2
- 390NampaIdaho 5.2
- 390North OgdenUtah 5.2
- 390AuburnWashington 5.2
- 413LeawoodKansas 5.1
- 413Lexington-FayetteKentucky 5.1
- 413LafayetteLouisiana 5.1
- 413Hunt ValleyMaryland 5.1
- 413Des PlainesIllinois 5.1
- 413Fall RiverMassachusetts 5.1
- 413YpsilantiMichigan 5.1
- 413BuffaloNew York 5.1
- 413YoungstownOhio 5.1
- 413MesaArizona 5.1
- 413OrcuttCalifornia 5.1
- 413Las VegasNevada 5.1
- 413AmarilloTexas 5.1
- 413LubbockTexas 5.1
- 413RentonWashington 5.1
- 428Belle GladeFlorida 5.0
- 428LebanonOhio 5.0
- 428MasonOhio 5.0
- 428CookevilleTennessee 5.0
- 428BloomingtonIllinois 5.0
- 428AndersonIndiana 5.0
- 428EastpointeMichigan 5.0
- 428LansingMichigan 5.0
- 428DublinOhio 5.0
- 428WeirtonWest Virginia 5.0
- 428GaltCalifornia 5.0
- 428Redwood CityCalifornia 5.0
- 428RosevilleCalifornia 5.0
- 428AlbuquerqueNew Mexico 5.0
- 428SunnysideWashington 5.0
- 428SheridanWyoming 5.0
- 428Arden-ArcadeCalifornia 5.0
- 428RandolphNew Jersey 5.0
- 446Coconut CreekFlorida 4.9
- 446AugustaMaine 4.9
- 446Port HuronMichigan 4.9
- 446SouthfieldMichigan 4.9
- 446MinneapolisMinnesota 4.9
- 446LindenNew Jersey 4.9
- 446BethlehemPennsylvania 4.9
- 446McKeesportPennsylvania 4.9
- 446Oconomowoclow-cost sensorsWisconsin 4.9
- 446PaysonArizona 4.9
- 446StocktonCalifornia 4.9
- 446Tularelow-cost sensorsCalifornia 4.9
- 446VallejoCalifornia 4.9
- 446ThorntonColorado 4.9
- 446MagnaUtah 4.9
- 461ZionIllinois 4.8
- 461ShakopeeMinnesota 4.8
- 461ParadiseCalifornia 4.8
- 461SacramentoCalifornia 4.8
- 461EnterpriseNevada 4.8
- 461RenoNevada 4.8
- 461Twin FallsIdaho 4.8
- 461TigardOregon 4.8
- 461KīheiHawaii 4.8
- 461Tri-CitiesWashington 4.8
- 471EdgewoodMaryland 4.7
- 471LynnMassachusetts 4.7
- 471LewistonMaine 4.7
- 471TaylorMichigan 4.7
- 471BurnsvilleMinnesota 4.7
- 471Saint PaulMinnesota 4.7
- 471MedinaOhio 4.7
- 471State CollegePennsylvania 4.7
- 471RutlandVermont 4.7
- 471LincolnCalifornia 4.7
- 471Spanish SpringsNevada 4.7
- 471ReddingCalifornia 4.7
- 471LongmontColorado 4.7
- 471BismarckNorth Dakota 4.7
- 471BendOregon 4.7
- 471WenatcheeWashington 4.7
- 487Fort SmithArkansas 4.6
- 487QuincyMassachusetts 4.6
- 487BangorMaine 4.6
- 487PortsmouthNew Hampshire 4.6
- 487PainesvilleOhio 4.6
- 487Shaker HeightsOhio 4.6
- 487EriePennsylvania 4.6
- 487BremertonWashington 4.6
- 487VancouverWashington 4.6
- 487Oxon Hill-GlassmanorMaryland 4.6
- 497McDonoughGeorgia 4.5
- 497Fort ThomasKentucky 4.5
- 497LibertyMissouri 4.5
- 497NorthbrookIllinois 4.5
- 497WorcesterMassachusetts 4.5
- 497Apple ValleyMinnesota 4.5
- 497Saint CloudMinnesota 4.5
- 497RochesterNew York 4.5
- 497HermitagePennsylvania 4.5
- 497Upper Saint ClairPennsylvania 4.5
- 497ConcordCalifornia 4.5
- 497LompocCalifornia 4.5
- 497Carson CityNevada 4.5
- 497HendersonNevada 4.5
- 497MesquiteNevada 4.5
- 497Spring ValleyNevada 4.5
- 497CanbyOregon 4.5
- 497KentWashington 4.5
- 497HonoluluHawaii 4.5
- 516FraminghamMassachusetts 4.4
- 516LowellMassachusetts 4.4
- 516MilfordMassachusetts 4.4
- 516BlaineMinnesota 4.4
- 516AlbanyNew York 4.4
- 516UkiahCalifornia 4.4
- 516Apache JunctionArizona 4.4
- 516PocatelloIdaho 4.4
- 516HighlandUtah 4.4
- 516Moses LakeWashington 4.4
- 516ShorelineWashington 4.4
- 516SpokaneWashington 4.4
- 528GreenfieldMassachusetts 4.3
- 528HaverhillMassachusetts 4.3
- 528PittsfieldMassachusetts 4.3
- 528Grand IslandNebraska 4.3
- 528Green BayWisconsin 4.3
- 528MadisonWisconsin 4.3
- 528Weirton HeightsWest Virginia 4.3
- 528Goletalow-cost sensorsCalifornia 4.3
- 528Colorado SpringsColorado 4.3
- 528Boulder CityNevada 4.3
- 528BozemanMontana 4.3
- 539HagerstownMaryland 4.2
- 539RaymoreMissouri 4.2
- 539North ChicopeeMassachusetts 4.2
- 539Saint MichaelMinnesota 4.2
- 539KeeneNew Hampshire 4.2
- 539AberdeenSouth Dakota 4.2
- 539AppletonWisconsin 4.2
- 539Los Banoslow-cost sensorsCalifornia 4.2
- 539DenverColorado 4.2
- 539GreshamOregon 4.2
- 539Summerlin SouthNevada 4.2
- 550RockvilleMaryland 4.1
- 550DerryNew Hampshire 4.1
- 550BayonneNew Jersey 4.1
- 550SyracuseNew York 4.1
- 550Eau ClaireWisconsin 4.1
- 550ModestoCalifornia 4.1
- 550Fort CollinsColorado 4.1
- 550GreeleyColorado 4.1
- 550ButteMontana 4.1
- 559La VistaNebraska 4.0
- 559AltoonaPennsylvania 4.0
- 559AlbanyOregon 4.0
- 559Coos BayOregon 4.0
- 559The DallesOregon 4.0
- 559BurienWashington 4.0
- 559Port AngelesWashington 4.0
- 559Salmon CreekWashington 4.0
- 559KahuluiHawaii 4.0
- 568White OakOhio 3.9
- 568Lexingtonlow-cost sensorsMassachusetts 3.9
- 568Cañon CityColorado 3.9
- 568PuebloColorado 3.9
- 568WindsorColorado 3.9
- 568Idaho FallsIdaho 3.9
- 568AltamontOregon 3.9
- 568HillsboroOregon 3.9
- 568MedfordOregon 3.9
- 568SalemOregon 3.9
- 568EllensburgWashington 3.9
- 568Spokane ValleyWashington 3.9
- 580HollandMichigan 3.8
- 580JohnstownPennsylvania 3.8
- 580ProvidenceRhode Island 3.8
- 580ChicoCalifornia 3.8
- 580Las CrucesNew Mexico 3.8
- 580BillingsMontana 3.8
- 580AshlandOregon 3.8
- 580EugeneOregon 3.8
- 580PortlandOregon 3.8
- 580YakimaWashington 3.8
- 580BadgerAlaska 3.8
- 591FairhopeAlabama 3.7
- 591ConwaySouth Carolina 3.7
- 591DuluthMinnesota 3.7
- 591TracyCalifornia 3.7
- 591BoiseIdaho 3.7
- 591Oregon CityOregon 3.7
- 597FolsomCalifornia 3.6
- 597Arvadalow-cost sensorsColorado 3.6
- 597HermistonOregon 3.6
- 597CentraliaWashington 3.6
- 601TruckeeCalifornia 3.5
- 601BeavertonOregon 3.5
- 601LaceyWashington 3.5
- 601Walla WallaWashington 3.5
- 605NewburghNew York 3.4
- 605BoulderColorado 3.4
- 605MoscowIdaho 3.4
- 605PullmanWashington 3.4
- 605HiloHawaii 3.4
- 610Green ValleyArizona 3.3
- 610MaranaArizona 3.3
- 610Ken CarylColorado 3.3
- 610AberdeenWashington 3.3
- 610ParklandWashington 3.3
- 615UticaNew York 3.2
- 615Brookfieldlow-cost sensorsWisconsin 3.2
- 615HelenaMontana 3.2
- 615MilwaukieOregon 3.2
- 615WoodburnOregon 3.2
- 615AnacortesWashington 3.2
- 621GahannaOhio 3.1
- 621CoventryRhode Island 3.1
- 621PawtucketRhode Island 3.1
- 621Sioux FallsSouth Dakota 3.1
- 621PendletonOregon 3.1
- 626VacavilleCalifornia 3.0
- 626Grand JunctionColorado 3.0
- 626Grants PassOregon 3.0
- 626RoseburgOregon 3.0
- 630HueytownAlabama 2.9
- 630White PlainsNew York 2.9
- 630CorvallisOregon 2.9
- 630LongviewWashington 2.9
- 634New CityNew York 2.8
- 634RedmondOregon 2.8
- 634BellevueWashington 2.8
- 634Mount VernonWashington 2.8
- 634CasperWyoming 2.8
- 639MarquetteMichigan 2.7
- 640Evanstonlow-cost sensorsIllinois 2.6
- 640DallasOregon 2.6
- 640McMinnvilleOregon 2.6
- 643Forest GroveOregon 2.5
- 644Palo Altolow-cost sensorsCalifornia 2.4
- 645LaconiaNew Hampshire 2.3
- 645MissoulaMontana 2.3
- 647Rock SpringsWyoming 2.2
- 648Kirklandlow-cost sensorsWashington 2.1
- 649CheyenneWyoming 2.0
- 649Union Hill-Novelty Hilllow-cost sensorsWashington 2.0
- 651Bothelllow-cost sensorsWashington 1.9
- 651LaramieWyoming 1.9
- 653FairbanksAlaska 1.6
- 654AnchorageAlaska 1.4
- 655Newtonlow-cost sensorsMassachusetts 1.3
- 656Middletonlow-cost sensorsWisconsin 1.1
- 657Loganlow-cost sensorsUtah 0.4
- 658Parkerlow-cost sensorsColorado 0.2
- 659Oro Valleylow-cost sensorsArizona 0.0
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+