SmogRank / Episodes / United States

North-western United States and Canada, July and August 2026

For 16 days, from 20 July to 4 August 2026, 66 cities in the United States and Canada had PM2.5 at least twice their usual for the time of year. The worst reading was Kamloops, British Columbia, Canada: 146.0 µg/m³ on 31 July, about 13× its usual 11.0.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached66in 2 countries
Days1620 July to 4 August 2026
Worst day3 August37 cities counted
Furthest above usual18×Wenatchee

Day by day

3 August 37 cities at twice their usual or more
Brigham CityNorth OgdenBountifulSalt Lake CityMagnaWest Valley CityMillcreekTooeleHerrimanHighlandRock SpringsOremSpanish ForkKennewickCedar CityLaramieSaskatoonHurricaneCheyenneSpanish SpringsMonroeUnion Hill-Novelty HillRedmondRenoAuburnRentonKentBellevueNorth CreekKirklandBothellInglewood-Finn HillMarysvilleColumbia CityGreshamBurienSeattleGoldenAltamontPicnic Point-North LynnwoodCarson CityParklandShorelineTacomaLakewoodOregon CityMount VernonSalmon CreekMilwaukieVancouverPortlandTruckeeCanbyBremertonTigardPrince AlbertBeavertonSouth Lake TahoeLaceyBellinghamWoodburnLongviewAnacortesCentraliaParkerHillsboroSalemForest GroveLangleyAlbanyMcMinnvilleEugenePort CoquitlamCoquitlamCorvallisDallasStrawberry HillAshlandBurnabyMedfordDeltaParadiseNorth VancouverRichmondVancouverVictoriaPort AngelesRoseburgWest VancouverCentral SaanichChicoReddingLangfordSquamishLincolnFolsomGrants PassRosevilleYuba CityNorth CowichanDuncanArden-ArcadeFlorinSacramentoElk GroveGaltMercedDavisStocktonTurlockModestoMantecaTracyVacavilleLos BanosLivermoreConcordVallejoUkiahSanta RosaFremontBerkeleySan LeandroRichmondOaklandGilroySan JoseSan RafaelSunnyvaleSan FranciscoMountain ViewPalo AltoRedwood CitySan MateoSouth San FranciscoPrince GeorgeReginaRapid CityGreeleyBozemanGreat FallsSheridanThorntonLongmontWest JordanLewistonDenverMoscowHelenaWindsorGilletteColorado SpringsSunnysideBoulderBillingsMedicine HatPullmanKen CarylPascoFort CollinsSwift CurrentCranbrookCasperPuebloAbbotsfordThe DallesLittletonEdmontonCañon CityArvadaHermistonButteSt. AlbertTri-CitiesMeridianMissoulaChilliwackLoganSherwood ParkCalgaryEllensburgYakimaCoeur d'AleneLethbridgePocatelloMoses LakeVernonRed DeerAirdrieSpokaneIdaho FallsSpokane ValleyBendRedmondPendletonKelownaKamloopsNampaBoiseWalla WallaWenatcheeTwin Falls
17 Jul202326291 Aug47
Every measured city in the area, coloured by its PM2.5 that day; a dark ring marks a city at twice its usual or more. Bars: cities counted each day, coloured by their median level. Choose a day or press play; without JavaScript, the days link to that day's world ranking.

How it spread

Spokane ValleySpokane Valley, 17 July: 123.0 µg/m³, 15× usualSpokane Valley, 18 July: 14.9 µg/m³, 1.8× usualSpokane Valley, 19 July: 11.7 µg/m³, 1.4× usualSpokane Valley, 20 July: 22.6 µg/m³, 2.8× usualSpokane Valley, 21 July: 26.5 µg/m³, 3.3× usualSpokane Valley, 22 July: 25.3 µg/m³, 3.1× usualSpokane Valley, 23 July: 27.3 µg/m³, 3.4× usualSpokane Valley, 24 July: 15.6 µg/m³, 1.9× usualSpokane Valley, 25 July: 12.5 µg/m³, 1.5× usualSpokane Valley, 26 July: 14.2 µg/m³, 1.8× usualSpokane Valley, 27 July: 17.1 µg/m³, 2.1× usualSpokane Valley, 28 July: 18.2 µg/m³, 2.2× usualSpokane Valley, 29 July: 17.0 µg/m³, 2.1× usualSpokane Valley, 30 July: 20.4 µg/m³, 2.5× usualSpokane Valley, 31 July: 17.9 µg/m³, 2.2× usualSpokane Valley, 1 August: 12.3 µg/m³, 1.5× usualSpokane Valley, 2 August: 58.9 µg/m³, 7.3× usualSpokane Valley, 3 August: 95.6 µg/m³, 12× usualSpokane Valley, 4 August: 64.5 µg/m³, 8.0× usualSpokane Valley, 5 August: 39.2 µg/m³, 4.8× usualSpokane Valley, 6 August: 53.4 µg/m³, 6.6× usualSpokane Valley, 7 August: 46.5 µg/m³, 5.7× usualSpokaneSpokane, 17 July: 98.1 µg/m³, 11× usualSpokane, 18 July: 11.7 µg/m³, 1.4× usualSpokane, 19 July: 20.9 µg/m³, 2.4× usualSpokane, 20 July: 31.5 µg/m³, 3.7× usualSpokane, 21 July: 35.5 µg/m³, 4.1× usualSpokane, 22 July: 28.5 µg/m³, 3.3× usualSpokane, 23 July: 32.4 µg/m³, 3.8× usualSpokane, 24 July: 16.4 µg/m³, 1.9× usualSpokane, 25 July: 12.1 µg/m³, 1.4× usualSpokane, 26 July: 9.8 µg/m³, 1.1× usualSpokane, 27 July: 18.0 µg/m³, 2.1× usualSpokane, 28 July: 17.0 µg/m³, 2.0× usualSpokane, 29 July: 20.6 µg/m³, 2.4× usualSpokane, 30 July: 19.8 µg/m³, 2.3× usualSpokane, 31 July: 20.3 µg/m³, 2.4× usualSpokane, 1 August: 15.0 µg/m³, 1.7× usualSpokane, 2 August: 58.5 µg/m³, 6.8× usualSpokane, 3 August: 93.1 µg/m³, 11× usualSpokane, 4 August: 68.6 µg/m³, 8.0× usualSpokane, 5 August: 45.2 µg/m³, 5.3× usualSpokane, 6 August: 54.4 µg/m³, 6.3× usualSpokane, 7 August: 49.3 µg/m³, 5.7× usualCoeur d'AleneCoeur d'Alene, 17 July: 97.8 µg/m³, 11× usualCoeur d'Alene, 18 July: 16.5 µg/m³, 1.9× usualCoeur d'Alene, 19 July: 6.1 µg/m³, 0.7× usualCoeur d'Alene, 20 July: 16.2 µg/m³, 1.8× usualCoeur d'Alene, 21 July: 20.6 µg/m³, 2.3× usualCoeur d'Alene, 22 July: 21.3 µg/m³, 2.4× usualCoeur d'Alene, 23 July: 24.0 µg/m³, 2.7× usualCoeur d'Alene, 24 July: 16.5 µg/m³, 1.9× usualCoeur d'Alene, 25 July: 12.2 µg/m³, 1.4× usualCoeur d'Alene, 26 July: 14.5 µg/m³, 1.6× usualCoeur d'Alene, 27 July: 24.1 µg/m³, 2.7× usualCoeur d'Alene, 28 July: 19.4 µg/m³, 2.2× usualCoeur d'Alene, 29 July: 18.2 µg/m³, 2.1× usualCoeur d'Alene, 30 July: no readingCoeur d'Alene, 31 July: 16.8 µg/m³, 1.9× usualCoeur d'Alene, 1 August: 9.9 µg/m³, 1.1× usualCoeur d'Alene, 2 August: 68.3 µg/m³, 7.8× usualCoeur d'Alene, 3 August: 76.0 µg/m³, 8.6× usualCoeur d'Alene, 4 August: 50.5 µg/m³, 5.7× usualCoeur d'Alene, 5 August: no readingCoeur d'Alene, 6 August: 44.7 µg/m³, 5.1× usualCoeur d'Alene, 7 August: 41.0 µg/m³, 4.7× usualPullmanPullman, 17 July: 26.4 µg/m³, 3.5× usualPullman, 18 July: 10.2 µg/m³, 1.4× usualPullman, 19 July: 5.3 µg/m³, 0.7× usualPullman, 20 July: 9.0 µg/m³, 1.2× usualPullman, 21 July: 27.1 µg/m³, 3.6× usualPullman, 22 July: 27.1 µg/m³, 3.6× usualPullman, 23 July: 36.4 µg/m³, 4.9× usualPullman, 24 July: 19.0 µg/m³, 2.5× usualPullman, 25 July: 14.7 µg/m³, 2.0× usualPullman, 26 July: 33.3 µg/m³, 4.4× usualPullman, 27 July: 32.1 µg/m³, 4.3× usualPullman, 28 July: 28.6 µg/m³, 3.8× usualPullman, 29 July: 13.7 µg/m³, 1.8× usualPullman, 30 July: 27.2 µg/m³, 3.6× usualPullman, 31 July: 23.5 µg/m³, 3.1× usualPullman, 1 August: 15.1 µg/m³, 2.0× usualPullman, 2 August: 9.1 µg/m³, 1.2× usualPullman, 3 August: 38.8 µg/m³, 5.2× usualPullman, 4 August: 41.0 µg/m³, 5.5× usualPullman, 5 August: 29.5 µg/m³, 3.9× usualPullman, 6 August: 52.8 µg/m³, 7.0× usualPullman, 7 August: 52.6 µg/m³, 7.0× usualMoscowMoscow, 17 July: 35.4 µg/m³, 3.8× usualMoscow, 18 July: 15.9 µg/m³, 1.7× usualMoscow, 19 July: 3.0 µg/m³, 0.3× usualMoscow, 20 July: 7.5 µg/m³, 0.8× usualMoscow, 21 July: 17.3 µg/m³, 1.9× usualMoscow, 22 July: 23.8 µg/m³, 2.6× usualMoscow, 23 July: 31.6 µg/m³, 3.4× usualMoscow, 24 July: 21.8 µg/m³, 2.4× usualMoscow, 25 July: 14.8 µg/m³, 1.6× usualMoscow, 26 July: 27.6 µg/m³, 3.0× usualMoscow, 27 July: 26.8 µg/m³, 2.9× usualMoscow, 28 July: 27.0 µg/m³, 2.9× usualMoscow, 29 July: 17.6 µg/m³, 1.9× usualMoscow, 30 July: 23.1 µg/m³, 2.5× usualMoscow, 31 July: 18.9 µg/m³, 2.1× usualMoscow, 1 August: 16.5 µg/m³, 1.8× usualMoscow, 2 August: 7.7 µg/m³, 0.8× usualMoscow, 3 August: 41.5 µg/m³, 4.5× usualMoscow, 4 August: 40.0 µg/m³, 4.3× usualMoscow, 5 August: 27.4 µg/m³, 3.0× usualMoscow, 6 August: 43.4 µg/m³, 4.7× usualMoscow, 7 August: 46.5 µg/m³, 5.1× usualNampaNampa, 17 July: 9.5 µg/m³, 1.1× usualNampa, 18 July: 26.7 µg/m³, 3.0× usualNampa, 19 July: 51.5 µg/m³, 5.9× usualNampa, 20 July: 57.0 µg/m³, 6.5× usualNampa, 21 July: 57.0 µg/m³, 6.5× usualNampa, 22 July: 45.5 µg/m³, 5.2× usualNampa, 23 July: 31.2 µg/m³, 3.5× usualNampa, 24 July: 29.1 µg/m³, 3.3× usualNampa, 25 July: 16.3 µg/m³, 1.9× usualNampa, 26 July: 115.0 µg/m³, 13× usualNampa, 27 July: 119.0 µg/m³, 14× usualNampa, 28 July: 100.0 µg/m³, 11× usualNampa, 29 July: 87.7 µg/m³, 10.0× usualNampa, 30 July: 57.0 µg/m³, 6.5× usualNampa, 31 July: 66.3 µg/m³, 7.5× usualNampa, 1 August: 39.2 µg/m³, 4.5× usualNampa, 2 August: 33.4 µg/m³, 3.8× usualNampa, 3 August: 65.3 µg/m³, 7.4× usualNampa, 4 August: 66.8 µg/m³, 7.6× usualNampa, 5 August: 38.1 µg/m³, 4.3× usualNampa, 6 August: 45.1 µg/m³, 5.1× usualNampa, 7 August: 77.5 µg/m³, 8.8× usualCalgaryCalgary, 17 July: 12.5 µg/m³, 1.1× usualCalgary, 18 July: 27.5 µg/m³, 2.4× usualCalgary, 19 July: 17.1 µg/m³, 1.5× usualCalgary, 20 July: 11.8 µg/m³, 1.0× usualCalgary, 21 July: 26.0 µg/m³, 2.3× usualCalgary, 22 July: 30.1 µg/m³, 2.7× usualCalgary, 23 July: 74.7 µg/m³, 6.6× usualCalgary, 24 July: 91.3 µg/m³, 8.1× usualCalgary, 25 July: 40.7 µg/m³, 3.6× usualCalgary, 26 July: 27.0 µg/m³, 2.4× usualCalgary, 27 July: 19.7 µg/m³, 1.7× usualCalgary, 28 July: 14.3 µg/m³, 1.3× usualCalgary, 29 July: 9.6 µg/m³, 0.8× usualCalgary, 30 July: 13.2 µg/m³, 1.2× usualCalgary, 31 July: 45.4 µg/m³, 4.0× usualCalgary, 1 August: 52.4 µg/m³, 4.6× usualCalgary, 2 August: 38.1 µg/m³, 3.4× usualCalgary, 3 August: 5.8 µg/m³, 0.5× usualCalgary, 4 August: 8.3 µg/m³, 0.7× usualCalgary, 5 August: 10.2 µg/m³, 0.9× usualCalgary, 6 August: 10.5 µg/m³, 0.9× usualCalgary, 7 August: 18.6 µg/m³, 1.6× usualCranbrookCranbrook, 17 July: 8.7 µg/m³, 1.1× usualCranbrook, 18 July: 35.8 µg/m³, 4.7× usualCranbrook, 19 July: 22.2 µg/m³, 2.9× usualCranbrook, 20 July: 17.9 µg/m³, 2.4× usualCranbrook, 21 July: 15.6 µg/m³, 2.1× usualCranbrook, 22 July: 24.2 µg/m³, 3.2× usualCranbrook, 23 July: 40.0 µg/m³, 5.3× usualCranbrook, 24 July: 40.9 µg/m³, 5.4× usualCranbrook, 25 July: 18.0 µg/m³, 2.4× usualCranbrook, 26 July: 7.4 µg/m³, 1.0× usualCranbrook, 27 July: 7.6 µg/m³, 1.0× usualCranbrook, 28 July: 20.0 µg/m³, 2.6× usualCranbrook, 29 July: 15.4 µg/m³, 2.0× usualCranbrook, 30 July: 21.4 µg/m³, 2.8× usualCranbrook, 31 July: 33.7 µg/m³, 4.4× usualCranbrook, 1 August: 14.5 µg/m³, 1.9× usualCranbrook, 2 August: 39.8 µg/m³, 5.2× usualCranbrook, 3 August: 22.2 µg/m³, 2.9× usualCranbrook, 4 August: 15.7 µg/m³, 2.1× usualCranbrook, 5 August: 26.0 µg/m³, 3.4× usualCranbrook, 6 August: 67.0 µg/m³, 8.8× usualCranbrook, 7 August: 84.2 µg/m³, 11× usualBoiseBoise, 17 July: 8.6 µg/m³, 1.3× usualBoise, 18 July: 19.6 µg/m³, 2.9× usualBoise, 19 July: 27.8 µg/m³, 4.1× usualBoise, 20 July: 32.8 µg/m³, 4.8× usualBoise, 21 July: 50.0 µg/m³, 7.4× usualBoise, 22 July: 42.1 µg/m³, 6.2× usualBoise, 23 July: 29.8 µg/m³, 4.4× usualBoise, 24 July: 19.8 µg/m³, 2.9× usualBoise, 25 July: 14.7 µg/m³, 2.2× usualBoise, 26 July: 81.4 µg/m³, 12× usualBoise, 27 July: 93.3 µg/m³, 14× usualBoise, 28 July: 57.2 µg/m³, 8.4× usualBoise, 29 July: 78.5 µg/m³, 12× usualBoise, 30 July: 37.3 µg/m³, 5.5× usualBoise, 31 July: 29.9 µg/m³, 4.4× usualBoise, 1 August: 36.3 µg/m³, 5.3× usualBoise, 2 August: 54.8 µg/m³, 8.1× usualBoise, 3 August: 52.1 µg/m³, 7.7× usualBoise, 4 August: 54.0 µg/m³, 7.9× usualBoise, 5 August: 26.9 µg/m³, 4.0× usualBoise, 6 August: 26.9 µg/m³, 4.0× usualBoise, 7 August: 54.7 µg/m³, 8.0× usualPendletonPendleton, 17 July: 18.8 µg/m³, 3.0× usualPendleton, 18 July: 9.0 µg/m³, 1.5× usualPendleton, 19 July: 8.7 µg/m³, 1.4× usualPendleton, 20 July: 62.4 µg/m³, 10× usualPendleton, 21 July: 75.1 µg/m³, 12× usualPendleton, 22 July: 62.7 µg/m³, 10× usualPendleton, 23 July: 34.9 µg/m³, 5.6× usualPendleton, 24 July: 22.4 µg/m³, 3.6× usualPendleton, 25 July: 11.6 µg/m³, 1.9× usualPendleton, 26 July: 13.1 µg/m³, 2.1× usualPendleton, 27 July: 36.5 µg/m³, 5.9× usualPendleton, 28 July: 33.2 µg/m³, 5.4× usualPendleton, 29 July: 19.8 µg/m³, 3.2× usualPendleton, 30 July: 25.2 µg/m³, 4.1× usualPendleton, 31 July: 40.0 µg/m³, 6.5× usualPendleton, 1 August: 14.3 µg/m³, 2.3× usualPendleton, 2 August: 7.7 µg/m³, 1.2× usualPendleton, 3 August: 31.3 µg/m³, 5.0× usualPendleton, 4 August: 78.6 µg/m³, 13× usualPendleton, 5 August: 86.3 µg/m³, 14× usualPendleton, 6 August: 78.2 µg/m³, 13× usualPendleton, 7 August: 48.1 µg/m³, 7.8× usualMoses LakeMoses Lake, 17 July: 11.5 µg/m³, 1.6× usualMoses Lake, 18 July: 4.4 µg/m³, 0.6× usualMoses Lake, 19 July: 7.1 µg/m³, 1.0× usualMoses Lake, 20 July: 43.7 µg/m³, 6.2× usualMoses Lake, 21 July: 59.3 µg/m³, 8.4× usualMoses Lake, 22 July: 50.3 µg/m³, 7.1× usualMoses Lake, 23 July: 22.9 µg/m³, 3.2× usualMoses Lake, 24 July: 15.7 µg/m³, 2.2× usualMoses Lake, 25 July: 5.3 µg/m³, 0.7× usualMoses Lake, 26 July: 3.8 µg/m³, 0.5× usualMoses Lake, 27 July: 7.5 µg/m³, 1.1× usualMoses Lake, 28 July: 8.7 µg/m³, 1.2× usualMoses Lake, 29 July: 4.3 µg/m³, 0.6× usualMoses Lake, 30 July: 6.2 µg/m³, 0.9× usualMoses Lake, 31 July: 8.1 µg/m³, 1.1× usualMoses Lake, 1 August: 5.1 µg/m³, 0.7× usualMoses Lake, 2 August: 34.8 µg/m³, 4.9× usualMoses Lake, 3 August: 69.6 µg/m³, 9.8× usualMoses Lake, 4 August: 85.1 µg/m³, 12× usualMoses Lake, 5 August: 69.3 µg/m³, 9.8× usualMoses Lake, 6 August: 58.1 µg/m³, 8.2× usualMoses Lake, 7 August: 40.4 µg/m³, 5.7× usualRedmondRedmond, 17 July: 10.3 µg/m³, 1.6× usualRedmond, 18 July: 13.4 µg/m³, 2.0× usualRedmond, 19 July: 11.1 µg/m³, 1.7× usualRedmond, 20 July: 25.6 µg/m³, 3.9× usualRedmond, 21 July: 50.6 µg/m³, 7.7× usualRedmond, 22 July: 69.6 µg/m³, 11× usualRedmond, 23 July: 79.3 µg/m³, 12× usualRedmond, 24 July: 15.5 µg/m³, 2.3× usualRedmond, 25 July: 8.3 µg/m³, 1.3× usualRedmond, 26 July: 6.1 µg/m³, 0.9× usualRedmond, 27 July: 4.9 µg/m³, 0.7× usualRedmond, 28 July: 3.3 µg/m³, 0.5× usualRedmond, 29 July: 20.2 µg/m³, 3.1× usualRedmond, 30 July: 8.1 µg/m³, 1.2× usualRedmond, 31 July: 21.5 µg/m³, 3.3× usualRedmond, 1 August: 2.7 µg/m³, 0.4× usualRedmond, 2 August: 3.0 µg/m³, 0.5× usualRedmond, 3 August: 29.1 µg/m³, 4.4× usualRedmond, 4 August: 69.8 µg/m³, 11× usualRedmond, 5 August: 62.0 µg/m³, 9.4× usualRedmond, 6 August: 37.9 µg/m³, 5.7× usualRedmond, 7 August: 21.4 µg/m³, 3.2× usualEdmontonEdmonton, 17 July: 14.9 µg/m³, 1.1× usualEdmonton, 18 July: 14.7 µg/m³, 1.1× usualEdmonton, 19 July: 14.1 µg/m³, 1.1× usualEdmonton, 20 July: 57.8 µg/m³, 4.4× usualEdmonton, 21 July: 76.3 µg/m³, 5.8× usualEdmonton, 22 July: 38.6 µg/m³, 2.9× usualEdmonton, 23 July: 26.0 µg/m³, 2.0× usualEdmonton, 24 July: 44.9 µg/m³, 3.4× usualEdmonton, 25 July: 15.3 µg/m³, 1.2× usualEdmonton, 26 July: 13.7 µg/m³, 1.0× usualEdmonton, 27 July: 24.2 µg/m³, 1.8× usualEdmonton, 28 July: 22.4 µg/m³, 1.7× usualEdmonton, 29 July: 8.3 µg/m³, 0.6× usualEdmonton, 30 July: 7.9 µg/m³, 0.6× usualEdmonton, 31 July: 11.9 µg/m³, 0.9× usualEdmonton, 1 August: 28.8 µg/m³, 2.2× usualEdmonton, 2 August: 10.0 µg/m³, 0.8× usualEdmonton, 3 August: 6.8 µg/m³, 0.5× usualEdmonton, 4 August: 9.0 µg/m³, 0.7× usualEdmonton, 5 August: 12.3 µg/m³, 0.9× usualEdmonton, 6 August: 12.1 µg/m³, 0.9× usualEdmonton, 7 August: 25.0 µg/m³, 1.9× usualSherwood ParkSherwood Park, 17 July: 11.7 µg/m³, 1.3× usualSherwood Park, 18 July: 12.6 µg/m³, 1.4× usualSherwood Park, 19 July: 12.5 µg/m³, 1.3× usualSherwood Park, 20 July: 56.2 µg/m³, 6.0× usualSherwood Park, 21 July: 74.6 µg/m³, 8.0× usualSherwood Park, 22 July: 34.4 µg/m³, 3.7× usualSherwood Park, 23 July: 24.1 µg/m³, 2.6× usualSherwood Park, 24 July: 42.2 µg/m³, 4.5× usualSherwood Park, 25 July: 11.9 µg/m³, 1.3× usualSherwood Park, 26 July: 11.9 µg/m³, 1.3× usualSherwood Park, 27 July: 21.1 µg/m³, 2.3× usualSherwood Park, 28 July: 19.6 µg/m³, 2.1× usualSherwood Park, 29 July: 6.7 µg/m³, 0.7× usualSherwood Park, 30 July: 5.6 µg/m³, 0.6× usualSherwood Park, 31 July: 9.4 µg/m³, 1.0× usualSherwood Park, 1 August: 27.0 µg/m³, 2.9× usualSherwood Park, 2 August: 8.8 µg/m³, 0.9× usualSherwood Park, 3 August: 4.3 µg/m³, 0.5× usualSherwood Park, 4 August: 6.9 µg/m³, 0.7× usualSherwood Park, 5 August: 11.1 µg/m³, 1.2× usualSherwood Park, 6 August: 7.0 µg/m³, 0.8× usualSherwood Park, 7 August: 20.3 µg/m³, 2.2× usualTri-CitiesTri-Cities, 17 July: 17.3 µg/m³, 3.5× usualTri-Cities, 18 July: 5.0 µg/m³, 1.0× usualTri-Cities, 19 July: 6.6 µg/m³, 1.3× usualTri-Cities, 20 July: 27.0 µg/m³, 5.4× usualTri-Cities, 21 July: 28.7 µg/m³, 5.7× usualTri-Cities, 22 July: 33.9 µg/m³, 6.8× usualTri-Cities, 23 July: 22.7 µg/m³, 4.5× usualTri-Cities, 24 July: 6.6 µg/m³, 1.3× usualTri-Cities, 25 July: 9.9 µg/m³, 2.0× usualTri-Cities, 26 July: 12.6 µg/m³, 2.5× usualTri-Cities, 27 July: 17.2 µg/m³, 3.4× usualTri-Cities, 28 July: 8.1 µg/m³, 1.6× usualTri-Cities, 29 July: 10.1 µg/m³, 2.0× usualTri-Cities, 30 July: 11.7 µg/m³, 2.3× usualTri-Cities, 31 July: 8.5 µg/m³, 1.7× usualTri-Cities, 1 August: 8.7 µg/m³, 1.7× usualTri-Cities, 2 August: 2.9 µg/m³, 0.6× usualTri-Cities, 3 August: 32.4 µg/m³, 6.5× usualTri-Cities, 4 August: 70.6 µg/m³, 14× usualTri-Cities, 5 August: 65.0 µg/m³, 13× usualTri-Cities, 6 August: 58.3 µg/m³, 12× usualTri-Cities, 7 August: 33.0 µg/m³, 6.6× usualSt. AlbertSt. Albert, 17 July: 12.7 µg/m³, 1.4× usualSt. Albert, 18 July: 12.5 µg/m³, 1.4× usualSt. Albert, 19 July: 11.8 µg/m³, 1.3× usualSt. Albert, 20 July: 50.9 µg/m³, 5.6× usualSt. Albert, 21 July: 59.8 µg/m³, 6.6× usualSt. Albert, 22 July: 37.6 µg/m³, 4.1× usualSt. Albert, 23 July: 21.6 µg/m³, 2.4× usualSt. Albert, 24 July: 35.9 µg/m³, 3.9× usualSt. Albert, 25 July: 10.8 µg/m³, 1.2× usualSt. Albert, 26 July: 10.4 µg/m³, 1.1× usualSt. Albert, 27 July: 20.1 µg/m³, 2.2× usualSt. Albert, 28 July: 20.1 µg/m³, 2.2× usualSt. Albert, 29 July: 5.3 µg/m³, 0.6× usualSt. Albert, 30 July: 5.3 µg/m³, 0.6× usualSt. Albert, 31 July: 10.2 µg/m³, 1.1× usualSt. Albert, 1 August: 26.4 µg/m³, 2.9× usualSt. Albert, 2 August: 7.1 µg/m³, 0.8× usualSt. Albert, 3 August: 5.5 µg/m³, 0.6× usualSt. Albert, 4 August: 5.6 µg/m³, 0.6× usualSt. Albert, 5 August: 9.3 µg/m³, 1.0× usualSt. Albert, 6 August: 9.8 µg/m³, 1.1× usualSt. Albert, 7 August: 20.5 µg/m³, 2.3× usualWenatcheeWenatchee, 17 July: 4.6 µg/m³, 0.9× usualWenatchee, 18 July: 3.9 µg/m³, 0.8× usualWenatchee, 19 July: 5.6 µg/m³, 1.1× usualWenatchee, 20 July: 13.8 µg/m³, 2.8× usualWenatchee, 21 July: 32.2 µg/m³, 6.4× usualWenatchee, 22 July: 30.7 µg/m³, 6.1× usualWenatchee, 23 July: 37.3 µg/m³, 7.5× usualWenatchee, 24 July: 12.7 µg/m³, 2.5× usualWenatchee, 25 July: 4.4 µg/m³, 0.9× usualWenatchee, 26 July: 3.3 µg/m³, 0.7× usualWenatchee, 27 July: 2.6 µg/m³, 0.5× usualWenatchee, 28 July: 2.8 µg/m³, 0.6× usualWenatchee, 29 July: 11.5 µg/m³, 2.3× usualWenatchee, 30 July: 4.3 µg/m³, 0.9× usualWenatchee, 31 July: 21.9 µg/m³, 4.4× usualWenatchee, 1 August: 4.9 µg/m³, 1.0× usualWenatchee, 2 August: 3.0 µg/m³, 0.6× usualWenatchee, 3 August: 79.7 µg/m³, 16× usualWenatchee, 4 August: 204.0 µg/m³, 41× usualWenatchee, 5 August: 146.0 µg/m³, 29× usualWenatchee, 6 August: 146.0 µg/m³, 29× usualWenatchee, 7 August: 99.9 µg/m³, 20× usualVernonVernon, 17 July: 16.2 µg/m³, 2.2× usualVernon, 18 July: 3.5 µg/m³, 0.5× usualVernon, 19 July: 10.2 µg/m³, 1.4× usualVernon, 20 July: 8.4 µg/m³, 1.2× usualVernon, 21 July: 29.7 µg/m³, 4.1× usualVernon, 22 July: 40.8 µg/m³, 5.6× usualVernon, 23 July: 72.0 µg/m³, 9.9× usualVernon, 24 July: 33.8 µg/m³, 4.6× usualVernon, 25 July: 13.6 µg/m³, 1.9× usualVernon, 26 July: 8.3 µg/m³, 1.1× usualVernon, 27 July: 9.2 µg/m³, 1.3× usualVernon, 28 July: 12.1 µg/m³, 1.7× usualVernon, 29 July: 4.5 µg/m³, 0.6× usualVernon, 30 July: 23.9 µg/m³, 3.3× usualVernon, 31 July: 68.9 µg/m³, 9.4× usualVernon, 1 August: 28.3 µg/m³, 3.9× usualVernon, 2 August: 26.4 µg/m³, 3.6× usualVernon, 3 August: 8.7 µg/m³, 1.2× usualVernon, 4 August: 19.3 µg/m³, 2.6× usualVernon, 5 August: 61.7 µg/m³, 8.5× usualVernon, 6 August: 122.0 µg/m³, 17× usualVernon, 7 August: 102.0 µg/m³, 14× usualWalla WallaWalla Walla, 17 July: 14.4 µg/m³, 2.4× usualWalla Walla, 18 July: 7.2 µg/m³, 1.2× usualWalla Walla, 19 July: 6.6 µg/m³, 1.1× usualWalla Walla, 20 July: 24.9 µg/m³, 4.1× usualWalla Walla, 21 July: 82.9 µg/m³, 14× usualWalla Walla, 22 July: 44.7 µg/m³, 7.5× usualWalla Walla, 23 July: 35.0 µg/m³, 5.8× usualWalla Walla, 24 July: 25.2 µg/m³, 4.2× usualWalla Walla, 25 July: 13.3 µg/m³, 2.2× usualWalla Walla, 26 July: 20.7 µg/m³, 3.4× usualWalla Walla, 27 July: 25.1 µg/m³, 4.2× usualWalla Walla, 28 July: 32.5 µg/m³, 5.4× usualWalla Walla, 29 July: 14.0 µg/m³, 2.3× usualWalla Walla, 30 July: 32.7 µg/m³, 5.5× usualWalla Walla, 31 July: 23.9 µg/m³, 4.0× usualWalla Walla, 1 August: 13.4 µg/m³, 2.2× usualWalla Walla, 2 August: 3.1 µg/m³, 0.5× usualWalla Walla, 3 August: 32.2 µg/m³, 5.4× usualWalla Walla, 4 August: 71.3 µg/m³, 12× usualWalla Walla, 5 August: 108.0 µg/m³, 18× usualWalla Walla, 6 August: 105.0 µg/m³, 18× usualWalla Walla, 7 August: 51.0 µg/m³, 8.5× usualRed DeerRed Deer, 17 July: 9.9 µg/m³, 1.0× usualRed Deer, 18 July: 17.5 µg/m³, 1.8× usualRed Deer, 19 July: 12.3 µg/m³, 1.3× usualRed Deer, 20 July: 22.1 µg/m³, 2.3× usualRed Deer, 21 July: 61.1 µg/m³, 6.3× usualRed Deer, 22 July: 25.0 µg/m³, 2.6× usualRed Deer, 23 July: 51.7 µg/m³, 5.3× usualRed Deer, 24 July: 99.4 µg/m³, 10× usualRed Deer, 25 July: 56.4 µg/m³, 5.8× usualRed Deer, 26 July: 14.3 µg/m³, 1.5× usualRed Deer, 27 July: 19.1 µg/m³, 2.0× usualRed Deer, 28 July: 16.4 µg/m³, 1.7× usualRed Deer, 29 July: 8.0 µg/m³, 0.8× usualRed Deer, 30 July: 11.1 µg/m³, 1.1× usualRed Deer, 31 July: 13.9 µg/m³, 1.4× usualRed Deer, 1 August: 32.8 µg/m³, 3.4× usualRed Deer, 2 August: 14.3 µg/m³, 1.5× usualRed Deer, 3 August: 6.6 µg/m³, 0.7× usualRed Deer, 4 August: 7.8 µg/m³, 0.8× usualRed Deer, 5 August: 7.3 µg/m³, 0.8× usualRed Deer, 6 August: 5.4 µg/m³, 0.6× usualRed Deer, 7 August: 8.9 µg/m³, 0.9× usualAirdrieAirdrie, 17 July: 8.4 µg/m³, 1.1× usualAirdrie, 18 July: 19.3 µg/m³, 2.4× usualAirdrie, 19 July: 14.9 µg/m³, 1.9× usualAirdrie, 20 July: 8.4 µg/m³, 1.1× usualAirdrie, 21 July: 30.1 µg/m³, 3.8× usualAirdrie, 22 July: 22.9 µg/m³, 2.9× usualAirdrie, 23 July: 65.1 µg/m³, 8.1× usualAirdrie, 24 July: 85.0 µg/m³, 11× usualAirdrie, 25 July: 39.5 µg/m³, 4.9× usualAirdrie, 26 July: 25.8 µg/m³, 3.2× usualAirdrie, 27 July: 21.9 µg/m³, 2.7× usualAirdrie, 28 July: 15.3 µg/m³, 1.9× usualAirdrie, 29 July: 9.0 µg/m³, 1.1× usualAirdrie, 30 July: 10.1 µg/m³, 1.3× usualAirdrie, 31 July: 40.8 µg/m³, 5.1× usualAirdrie, 1 August: 48.2 µg/m³, 6.0× usualAirdrie, 2 August: 33.4 µg/m³, 4.2× usualAirdrie, 3 August: 5.0 µg/m³, 0.6× usualAirdrie, 4 August: 6.4 µg/m³, 0.8× usualAirdrie, 5 August: 7.2 µg/m³, 0.9× usualAirdrie, 6 August: 7.1 µg/m³, 0.9× usualAirdrie, 7 August: 15.9 µg/m³, 2.0× usualEllensburgEllensburg, 17 July: 2.7 µg/m³, 0.5× usualEllensburg, 18 July: 3.8 µg/m³, 0.7× usualEllensburg, 19 July: 4.7 µg/m³, 0.9× usualEllensburg, 20 July: 16.3 µg/m³, 3.0× usualEllensburg, 21 July: 28.7 µg/m³, 5.2× usualEllensburg, 22 July: 21.3 µg/m³, 3.9× usualEllensburg, 23 July: 8.6 µg/m³, 1.6× usualEllensburg, 24 July: 7.2 µg/m³, 1.3× usualEllensburg, 25 July: 6.1 µg/m³, 1.1× usualEllensburg, 26 July: 3.0 µg/m³, 0.5× usualEllensburg, 27 July: 3.8 µg/m³, 0.7× usualEllensburg, 28 July: 4.3 µg/m³, 0.8× usualEllensburg, 29 July: 2.3 µg/m³, 0.4× usualEllensburg, 30 July: 5.4 µg/m³, 1.0× usualEllensburg, 31 July: 5.3 µg/m³, 1.0× usualEllensburg, 1 August: 4.1 µg/m³, 0.7× usualEllensburg, 2 August: 4.3 µg/m³, 0.8× usualEllensburg, 3 August: 45.1 µg/m³, 8.2× usualEllensburg, 4 August: 84.0 µg/m³, 15× usualEllensburg, 5 August: 83.9 µg/m³, 15× usualEllensburg, 6 August: 43.2 µg/m³, 7.9× usualEllensburg, 7 August: 24.7 µg/m³, 4.5× usualChilliwackChilliwack, 17 July: 5.9 µg/m³, 1.1× usualChilliwack, 18 July: 4.3 µg/m³, 0.8× usualChilliwack, 19 July: 4.8 µg/m³, 0.9× usualChilliwack, 20 July: 17.8 µg/m³, 3.2× usualChilliwack, 21 July: 29.4 µg/m³, 5.3× usualChilliwack, 22 July: 42.2 µg/m³, 7.5× usualChilliwack, 23 July: 13.8 µg/m³, 2.5× usualChilliwack, 24 July: 5.1 µg/m³, 0.9× usualChilliwack, 25 July: 4.0 µg/m³, 0.7× usualChilliwack, 26 July: 3.2 µg/m³, 0.6× usualChilliwack, 27 July: 3.3 µg/m³, 0.6× usualChilliwack, 28 July: 3.1 µg/m³, 0.6× usualChilliwack, 29 July: 3.7 µg/m³, 0.7× usualChilliwack, 30 July: 4.6 µg/m³, 0.8× usualChilliwack, 31 July: 4.3 µg/m³, 0.8× usualChilliwack, 1 August: 2.7 µg/m³, 0.5× usualChilliwack, 2 August: 3.0 µg/m³, 0.5× usualChilliwack, 3 August: 14.5 µg/m³, 2.6× usualChilliwack, 4 August: 52.1 µg/m³, 9.3× usualChilliwack, 5 August: 81.5 µg/m³, 15× usualChilliwack, 6 August: 51.5 µg/m³, 9.2× usualChilliwack, 7 August: 19.9 µg/m³, 3.6× usualHermistonHermiston, 17 July: 15.0 µg/m³, 2.7× usualHermiston, 18 July: 5.4 µg/m³, 1.0× usualHermiston, 19 July: 5.2 µg/m³, 0.9× usualHermiston, 20 July: 18.7 µg/m³, 3.3× usualHermiston, 21 July: 28.5 µg/m³, 5.1× usualHermiston, 22 July: 33.4 µg/m³, 6.0× usualHermiston, 23 July: 22.6 µg/m³, 4.0× usualHermiston, 24 July: 8.4 µg/m³, 1.5× usualHermiston, 25 July: 8.3 µg/m³, 1.5× usualHermiston, 26 July: 10.4 µg/m³, 1.9× usualHermiston, 27 July: 25.6 µg/m³, 4.6× usualHermiston, 28 July: 11.1 µg/m³, 2.0× usualHermiston, 29 July: 14.6 µg/m³, 2.6× usualHermiston, 30 July: 11.4 µg/m³, 2.0× usualHermiston, 31 July: 8.8 µg/m³, 1.6× usualHermiston, 1 August: 5.8 µg/m³, 1.0× usualHermiston, 2 August: 5.3 µg/m³, 0.9× usualHermiston, 3 August: 22.8 µg/m³, 4.1× usualHermiston, 4 August: 60.4 µg/m³, 11× usualHermiston, 5 August: 64.9 µg/m³, 12× usualHermiston, 6 August: 66.1 µg/m³, 12× usualHermiston, 7 August: 34.4 µg/m³, 6.1× usualBendBend, 17 July: 8.6 µg/m³, 1.7× usualBend, 18 July: 8.1 µg/m³, 1.6× usualBend, 19 July: 8.9 µg/m³, 1.8× usualBend, 20 July: 21.5 µg/m³, 4.3× usualBend, 21 July: 59.1 µg/m³, 12× usualBend, 22 July: 41.0 µg/m³, 8.2× usualBend, 23 July: 40.3 µg/m³, 8.1× usualBend, 24 July: 9.4 µg/m³, 1.9× usualBend, 25 July: 6.7 µg/m³, 1.3× usualBend, 26 July: 3.5 µg/m³, 0.7× usualBend, 27 July: 3.6 µg/m³, 0.7× usualBend, 28 July: 3.3 µg/m³, 0.7× usualBend, 29 July: 8.3 µg/m³, 1.7× usualBend, 30 July: 4.2 µg/m³, 0.8× usualBend, 31 July: 16.1 µg/m³, 3.2× usualBend, 1 August: 3.2 µg/m³, 0.6× usualBend, 2 August: 3.1 µg/m³, 0.6× usualBend, 3 August: 18.8 µg/m³, 3.8× usualBend, 4 August: 64.1 µg/m³, 13× usualBend, 5 August: 50.1 µg/m³, 10× usualBend, 6 August: 24.9 µg/m³, 5.0× usualBend, 7 August: 18.0 µg/m³, 3.6× usualLewistonLewiston, 17 July: 23.7 µg/m³, 2.7× usualLewiston, 18 July: 17.1 µg/m³, 1.9× usualLewiston, 19 July: 11.1 µg/m³, 1.3× usualLewiston, 20 July: 15.6 µg/m³, 1.8× usualLewiston, 21 July: 25.6 µg/m³, 2.9× usualLewiston, 22 July: 31.8 µg/m³, 3.6× usualLewiston, 23 July: 33.4 µg/m³, 3.8× usualLewiston, 24 July: 30.3 µg/m³, 3.4× usualLewiston, 25 July: 22.9 µg/m³, 2.6× usualLewiston, 26 July: 30.4 µg/m³, 3.5× usualLewiston, 27 July: 38.7 µg/m³, 4.4× usualLewiston, 28 July: 38.5 µg/m³, 4.4× usualLewiston, 29 July: 27.7 µg/m³, 3.1× usualLewiston, 30 July: 30.4 µg/m³, 3.5× usualLewiston, 31 July: 33.6 µg/m³, 3.8× usualLewiston, 1 August: 29.3 µg/m³, 3.3× usualLewiston, 2 August: 6.5 µg/m³, 0.7× usualLewiston, 3 August: 32.2 µg/m³, 3.7× usualLewiston, 4 August: 43.4 µg/m³, 4.9× usualLewiston, 5 August: 32.1 µg/m³, 3.6× usualLewiston, 6 August: 46.6 µg/m³, 5.3× usualLewiston, 7 August: 51.9 µg/m³, 5.9× usualSwift CurrentSwift Current, 17 July: 9.9 µg/m³, 1.0× usualSwift Current, 18 July: 7.5 µg/m³, 0.8× usualSwift Current, 19 July: 12.9 µg/m³, 1.3× usualSwift Current, 20 July: 14.2 µg/m³, 1.5× usualSwift Current, 21 July: 25.1 µg/m³, 2.6× usualSwift Current, 22 July: 23.2 µg/m³, 2.4× usualSwift Current, 23 July: 26.2 µg/m³, 2.7× usualSwift Current, 24 July: 51.6 µg/m³, 5.4× usualSwift Current, 25 July: 49.9 µg/m³, 5.2× usualSwift Current, 26 July: 33.0 µg/m³, 3.4× usualSwift Current, 27 July: 25.1 µg/m³, 2.6× usualSwift Current, 28 July: 17.8 µg/m³, 1.9× usualSwift Current, 29 July: 20.7 µg/m³, 2.2× usualSwift Current, 30 July: 11.3 µg/m³, 1.2× usualSwift Current, 31 July: 19.9 µg/m³, 2.1× usualSwift Current, 1 August: 26.3 µg/m³, 2.7× usualSwift Current, 2 August: 44.4 µg/m³, 4.6× usualSwift Current, 3 August: 3.0 µg/m³, 0.3× usualSwift Current, 4 August: 7.0 µg/m³, 0.7× usualSwift Current, 5 August: 7.8 µg/m³, 0.8× usualSwift Current, 6 August: 6.4 µg/m³, 0.7× usualSwift Current, 7 August: 8.8 µg/m³, 0.9× usualAbbotsfordAbbotsford, 17 July: 5.6 µg/m³, 1.1× usualAbbotsford, 18 July: 4.0 µg/m³, 0.8× usualAbbotsford, 19 July: 5.2 µg/m³, 1.0× usualAbbotsford, 20 July: 11.6 µg/m³, 2.3× usualAbbotsford, 21 July: 25.0 µg/m³, 5.0× usualAbbotsford, 22 July: 27.9 µg/m³, 5.6× usualAbbotsford, 23 July: 11.7 µg/m³, 2.3× usualAbbotsford, 24 July: 4.1 µg/m³, 0.8× usualAbbotsford, 25 July: 3.1 µg/m³, 0.6× usualAbbotsford, 26 July: 2.2 µg/m³, 0.4× usualAbbotsford, 27 July: 3.3 µg/m³, 0.7× usualAbbotsford, 28 July: 3.0 µg/m³, 0.6× usualAbbotsford, 29 July: 4.5 µg/m³, 0.9× usualAbbotsford, 30 July: 4.5 µg/m³, 0.9× usualAbbotsford, 31 July: 5.1 µg/m³, 1.0× usualAbbotsford, 1 August: 2.4 µg/m³, 0.5× usualAbbotsford, 2 August: 3.3 µg/m³, 0.7× usualAbbotsford, 3 August: 7.6 µg/m³, 1.5× usualAbbotsford, 4 August: 18.4 µg/m³, 3.7× usualAbbotsford, 5 August: 50.1 µg/m³, 10× usualAbbotsford, 6 August: 37.9 µg/m³, 7.6× usualAbbotsford, 7 August: 16.9 µg/m³, 3.4× usualKamloopsKamloops, 17 July: 19.9 µg/m³, 1.8× usualKamloops, 18 July: 4.3 µg/m³, 0.4× usualKamloops, 19 July: 9.7 µg/m³, 0.9× usualKamloops, 20 July: 12.0 µg/m³, 1.1× usualKamloops, 21 July: 20.0 µg/m³, 1.8× usualKamloops, 22 July: 51.9 µg/m³, 4.7× usualKamloops, 23 July: 85.1 µg/m³, 7.7× usualKamloops, 24 July: 87.9 µg/m³, 8.0× usualKamloops, 25 July: 45.0 µg/m³, 4.1× usualKamloops, 26 July: 8.4 µg/m³, 0.8× usualKamloops, 27 July: 12.1 µg/m³, 1.1× usualKamloops, 28 July: 13.5 µg/m³, 1.2× usualKamloops, 29 July: 13.1 µg/m³, 1.2× usualKamloops, 30 July: 86.8 µg/m³, 7.9× usualKamloops, 31 July: 146.0 µg/m³, 13× usualKamloops, 1 August: 79.2 µg/m³, 7.2× usualKamloops, 2 August: 25.3 µg/m³, 2.3× usualKamloops, 3 August: 6.1 µg/m³, 0.6× usualKamloops, 4 August: 31.8 µg/m³, 2.9× usualKamloops, 5 August: 73.2 µg/m³, 6.7× usualKamloops, 6 August: 146.0 µg/m³, 13× usualKamloops, 7 August: 191.0 µg/m³, 17× usualThe DallesThe Dalles, 17 July: 4.2 µg/m³, 0.8× usualThe Dalles, 18 July: 4.2 µg/m³, 0.8× usualThe Dalles, 19 July: 4.1 µg/m³, 0.8× usualThe Dalles, 20 July: 6.5 µg/m³, 1.3× usualThe Dalles, 21 July: 19.1 µg/m³, 3.8× usualThe Dalles, 22 July: 25.9 µg/m³, 5.2× usualThe Dalles, 23 July: 7.1 µg/m³, 1.4× usualThe Dalles, 24 July: 4.6 µg/m³, 0.9× usualThe Dalles, 25 July: 4.1 µg/m³, 0.8× usualThe Dalles, 26 July: 4.0 µg/m³, 0.8× usualThe Dalles, 27 July: 3.8 µg/m³, 0.8× usualThe Dalles, 28 July: 3.2 µg/m³, 0.6× usualThe Dalles, 29 July: 3.4 µg/m³, 0.7× usualThe Dalles, 30 July: 3.5 µg/m³, 0.7× usualThe Dalles, 31 July: 7.5 µg/m³, 1.5× usualThe Dalles, 1 August: 2.9 µg/m³, 0.6× usualThe Dalles, 2 August: 3.8 µg/m³, 0.8× usualThe Dalles, 3 August: 28.6 µg/m³, 5.7× usualThe Dalles, 4 August: 58.6 µg/m³, 12× usualThe Dalles, 5 August: 77.3 µg/m³, 15× usualThe Dalles, 6 August: 83.8 µg/m³, 17× usualThe Dalles, 7 August: 19.3 µg/m³, 3.9× usualKelownaKelowna, 17 July: 22.7 µg/m³, 3.4× usualKelowna, 18 July: 1.5 µg/m³, 0.2× usualKelowna, 19 July: 10.8 µg/m³, 1.6× usualKelowna, 20 July: no readingKelowna, 21 July: no readingKelowna, 22 July: 39.4 µg/m³, 5.9× usualKelowna, 23 July: 82.4 µg/m³, 12× usualKelowna, 24 July: 8.0 µg/m³, 1.2× usualKelowna, 25 July: 7.3 µg/m³, 1.1× usualKelowna, 26 July: 7.2 µg/m³, 1.1× usualKelowna, 27 July: 10.3 µg/m³, 1.5× usualKelowna, 28 July: 9.7 µg/m³, 1.4× usualKelowna, 29 July: 4.3 µg/m³, 0.6× usualKelowna, 30 July: 15.6 µg/m³, 2.3× usualKelowna, 31 July: 13.6 µg/m³, 2.0× usualKelowna, 1 August: 22.4 µg/m³, 3.3× usualKelowna, 2 August: 3.1 µg/m³, 0.5× usualKelowna, 3 August: 14.8 µg/m³, 2.2× usualKelowna, 4 August: 18.4 µg/m³, 2.7× usualKelowna, 5 August: 39.6 µg/m³, 5.9× usualKelowna, 6 August: 67.1 µg/m³, 10× usualKelowna, 7 August: 59.8 µg/m³, 8.9× usualSunnysideSunnyside, 17 July: 4.0 µg/m³, 0.5× usualSunnyside, 18 July: 3.0 µg/m³, 0.4× usualSunnyside, 19 July: 4.3 µg/m³, 0.6× usualSunnyside, 20 July: 11.4 µg/m³, 1.5× usualSunnyside, 21 July: 23.6 µg/m³, 3.1× usualSunnyside, 22 July: 27.3 µg/m³, 3.6× usualSunnyside, 23 July: 17.6 µg/m³, 2.3× usualSunnyside, 24 July: 6.3 µg/m³, 0.8× usualSunnyside, 25 July: 16.3 µg/m³, 2.2× usualSunnyside, 26 July: 4.5 µg/m³, 0.6× usualSunnyside, 27 July: 15.5 µg/m³, 2.1× usualSunnyside, 28 July: 5.6 µg/m³, 0.7× usualSunnyside, 29 July: 4.6 µg/m³, 0.6× usualSunnyside, 30 July: 12.5 µg/m³, 1.7× usualSunnyside, 31 July: 12.3 µg/m³, 1.6× usualSunnyside, 1 August: 9.4 µg/m³, 1.3× usualSunnyside, 2 August: 4.3 µg/m³, 0.6× usualSunnyside, 3 August: 37.1 µg/m³, 4.9× usualSunnyside, 4 August: 76.8 µg/m³, 10× usualSunnyside, 5 August: 67.0 µg/m³, 8.9× usualSunnyside, 6 August: 49.6 µg/m³, 6.6× usualSunnyside, 7 August: 26.8 µg/m³, 3.6× usualLethbridgeLethbridge, 17 July: 11.1 µg/m³, 1.2× usualLethbridge, 18 July: 10.5 µg/m³, 1.1× usualLethbridge, 19 July: 20.4 µg/m³, 2.2× usualLethbridge, 20 July: 11.6 µg/m³, 1.2× usualLethbridge, 21 July: 14.8 µg/m³, 1.6× usualLethbridge, 22 July: 18.4 µg/m³, 2.0× usualLethbridge, 23 July: 47.8 µg/m³, 5.1× usualLethbridge, 24 July: 40.8 µg/m³, 4.4× usualLethbridge, 25 July: 19.5 µg/m³, 2.1× usualLethbridge, 26 July: 22.6 µg/m³, 2.4× usualLethbridge, 27 July: 15.9 µg/m³, 1.7× usualLethbridge, 28 July: 26.5 µg/m³, 2.8× usualLethbridge, 29 July: 14.6 µg/m³, 1.6× usualLethbridge, 30 July: 22.3 µg/m³, 2.4× usualLethbridge, 31 July: 41.5 µg/m³, 4.5× usualLethbridge, 1 August: 52.1 µg/m³, 5.6× usualLethbridge, 2 August: 86.2 µg/m³, 9.3× usualLethbridge, 3 August: 4.1 µg/m³, 0.4× usualLethbridge, 4 August: 12.0 µg/m³, 1.3× usualLethbridge, 5 August: 11.9 µg/m³, 1.3× usualLethbridge, 6 August: 15.7 µg/m³, 1.7× usualLethbridge, 7 August: 19.2 µg/m³, 2.1× usualMedicine HatMedicine Hat, 17 July: 8.3 µg/m³, 0.8× usualMedicine Hat, 18 July: 8.2 µg/m³, 0.8× usualMedicine Hat, 19 July: 15.7 µg/m³, 1.6× usualMedicine Hat, 20 July: 12.4 µg/m³, 1.3× usualMedicine Hat, 21 July: 18.9 µg/m³, 1.9× usualMedicine Hat, 22 July: 17.0 µg/m³, 1.7× usualMedicine Hat, 23 July: 33.7 µg/m³, 3.4× usualMedicine Hat, 24 July: 49.3 µg/m³, 5.0× usualMedicine Hat, 25 July: 28.0 µg/m³, 2.9× usualMedicine Hat, 26 July: 38.2 µg/m³, 3.9× usualMedicine Hat, 27 July: 33.2 µg/m³, 3.4× usualMedicine Hat, 28 July: 32.1 µg/m³, 3.3× usualMedicine Hat, 29 July: 19.4 µg/m³, 2.0× usualMedicine Hat, 30 July: 17.7 µg/m³, 1.8× usualMedicine Hat, 31 July: 24.8 µg/m³, 2.5× usualMedicine Hat, 1 August: 30.3 µg/m³, 3.1× usualMedicine Hat, 2 August: 51.3 µg/m³, 5.2× usualMedicine Hat, 3 August: 3.5 µg/m³, 0.4× usualMedicine Hat, 4 August: 9.1 µg/m³, 0.9× usualMedicine Hat, 5 August: 9.4 µg/m³, 1.0× usualMedicine Hat, 6 August: 8.6 µg/m³, 0.9× usualMedicine Hat, 7 August: 9.3 µg/m³, 0.9× usualReginaRegina, 17 July: no readingRegina, 18 July: no readingRegina, 19 July: no readingRegina, 20 July: no readingRegina, 21 July: no readingRegina, 22 July: no readingRegina, 23 July: 28.4 µg/m³, 2.2× usualRegina, 24 July: 24.9 µg/m³, 1.9× usualRegina, 25 July: no readingRegina, 26 July: no readingRegina, 27 July: 23.8 µg/m³, 1.8× usualRegina, 28 July: 22.0 µg/m³, 1.7× usualRegina, 29 July: 20.1 µg/m³, 1.5× usualRegina, 30 July: 15.6 µg/m³, 1.2× usualRegina, 31 July: 14.6 µg/m³, 1.1× usualRegina, 1 August: 19.1 µg/m³, 1.4× usualRegina, 2 August: 35.9 µg/m³, 2.7× usualRegina, 3 August: 8.4 µg/m³, 0.6× usualRegina, 4 August: 5.2 µg/m³, 0.4× usualRegina, 5 August: 8.2 µg/m³, 0.6× usualRegina, 6 August: 6.9 µg/m³, 0.5× usualRegina, 7 August: 5.3 µg/m³, 0.4× usualTwin FallsTwin Falls, 17 July: 5.5 µg/m³, 0.8× usualTwin Falls, 18 July: 5.0 µg/m³, 0.8× usualTwin Falls, 19 July: 13.4 µg/m³, 2.0× usualTwin Falls, 20 July: 16.4 µg/m³, 2.5× usualTwin Falls, 21 July: 17.9 µg/m³, 2.7× usualTwin Falls, 22 July: 23.5 µg/m³, 3.6× usualTwin Falls, 23 July: 21.6 µg/m³, 3.3× usualTwin Falls, 24 July: 9.1 µg/m³, 1.4× usualTwin Falls, 25 July: 4.2 µg/m³, 0.6× usualTwin Falls, 26 July: 68.1 µg/m³, 10× usualTwin Falls, 27 July: 121.0 µg/m³, 18× usualTwin Falls, 28 July: 52.8 µg/m³, 8.0× usualTwin Falls, 29 July: 51.2 µg/m³, 7.8× usualTwin Falls, 30 July: 9.3 µg/m³, 1.4× usualTwin Falls, 31 July: 13.4 µg/m³, 2.0× usualTwin Falls, 1 August: 13.8 µg/m³, 2.1× usualTwin Falls, 2 August: 53.1 µg/m³, 8.0× usualTwin Falls, 3 August: 25.0 µg/m³, 3.8× usualTwin Falls, 4 August: 56.1 µg/m³, 8.5× usualTwin Falls, 5 August: 30.0 µg/m³, 4.5× usualTwin Falls, 6 August: 18.0 µg/m³, 2.7× usualTwin Falls, 7 August: 28.2 µg/m³, 4.3× usualMissoulaMissoula, 17 July: 4.2 µg/m³, 0.6× usualMissoula, 18 July: 2.8 µg/m³, 0.4× usualMissoula, 19 July: 10.6 µg/m³, 1.6× usualMissoula, 20 July: 7.8 µg/m³, 1.2× usualMissoula, 21 July: 10.1 µg/m³, 1.5× usualMissoula, 22 July: 18.9 µg/m³, 2.8× usualMissoula, 23 July: 20.5 µg/m³, 3.1× usualMissoula, 24 July: 12.1 µg/m³, 1.8× usualMissoula, 25 July: 20.8 µg/m³, 3.1× usualMissoula, 26 July: 39.9 µg/m³, 6.0× usualMissoula, 27 July: 34.1 µg/m³, 5.1× usualMissoula, 28 July: 27.8 µg/m³, 4.1× usualMissoula, 29 July: 27.4 µg/m³, 4.1× usualMissoula, 30 July: 26.5 µg/m³, 4.0× usualMissoula, 31 July: 23.3 µg/m³, 3.5× usualMissoula, 1 August: 25.4 µg/m³, 3.8× usualMissoula, 2 August: 18.9 µg/m³, 2.8× usualMissoula, 3 August: 49.4 µg/m³, 7.4× usualMissoula, 4 August: 23.1 µg/m³, 3.4× usualMissoula, 5 August: 22.0 µg/m³, 3.3× usualMissoula, 6 August: 39.5 µg/m³, 5.9× usualMissoula, 7 August: 37.6 µg/m³, 5.6× usualGreat FallsGreat Falls, 17 July: 8.7 µg/m³, 0.7× usualGreat Falls, 18 July: 9.2 µg/m³, 0.7× usualGreat Falls, 19 July: no readingGreat Falls, 20 July: no readingGreat Falls, 21 July: 14.0 µg/m³, 1.1× usualGreat Falls, 22 July: 18.4 µg/m³, 1.4× usualGreat Falls, 23 July: 20.2 µg/m³, 1.6× usualGreat Falls, 24 July: 19.8 µg/m³, 1.5× usualGreat Falls, 25 July: 15.4 µg/m³, 1.2× usualGreat Falls, 26 July: 36.7 µg/m³, 2.8× usualGreat Falls, 27 July: 48.4 µg/m³, 3.8× usualGreat Falls, 28 July: 31.1 µg/m³, 2.4× usualGreat Falls, 29 July: 33.0 µg/m³, 2.6× usualGreat Falls, 30 July: 25.5 µg/m³, 2.0× usualGreat Falls, 31 July: 24.1 µg/m³, 1.9× usualGreat Falls, 1 August: 31.4 µg/m³, 2.4× usualGreat Falls, 2 August: 38.0 µg/m³, 2.9× usualGreat Falls, 3 August: 18.9 µg/m³, 1.5× usualGreat Falls, 4 August: 16.4 µg/m³, 1.3× usualGreat Falls, 5 August: 18.0 µg/m³, 1.4× usualGreat Falls, 6 August: 28.0 µg/m³, 2.2× usualGreat Falls, 7 August: 23.6 µg/m³, 1.8× usualIdaho FallsIdaho Falls, 17 July: no readingIdaho Falls, 18 July: 5.2 µg/m³, 0.8× usualIdaho Falls, 19 July: 5.4 µg/m³, 0.9× usualIdaho Falls, 20 July: 6.5 µg/m³, 1.0× usualIdaho Falls, 21 July: 11.7 µg/m³, 1.9× usualIdaho Falls, 22 July: 10.6 µg/m³, 1.7× usualIdaho Falls, 23 July: 8.4 µg/m³, 1.4× usualIdaho Falls, 24 July: 6.5 µg/m³, 1.0× usualIdaho Falls, 25 July: 6.0 µg/m³, 1.0× usualIdaho Falls, 26 July: 5.6 µg/m³, 0.9× usualIdaho Falls, 27 July: 71.1 µg/m³, 11× usualIdaho Falls, 28 July: 8.7 µg/m³, 1.4× usualIdaho Falls, 29 July: 6.3 µg/m³, 1.0× usualIdaho Falls, 30 July: 6.8 µg/m³, 1.1× usualIdaho Falls, 31 July: 9.7 µg/m³, 1.6× usualIdaho Falls, 1 August: 7.7 µg/m³, 1.2× usualIdaho Falls, 2 August: 44.9 µg/m³, 7.2× usualIdaho Falls, 3 August: 19.4 µg/m³, 3.1× usualIdaho Falls, 4 August: 22.9 µg/m³, 3.7× usualIdaho Falls, 5 August: 19.6 µg/m³, 3.2× usualIdaho Falls, 6 August: 20.1 µg/m³, 3.2× usualIdaho Falls, 7 August: 21.3 µg/m³, 3.4× usualButteButte, 17 July: 5.8 µg/m³, 0.9× usualButte, 18 July: 6.7 µg/m³, 1.0× usualButte, 19 July: 9.2 µg/m³, 1.4× usualButte, 20 July: 12.0 µg/m³, 1.8× usualButte, 21 July: 12.7 µg/m³, 1.9× usualButte, 22 July: 12.5 µg/m³, 1.9× usualButte, 23 July: 13.8 µg/m³, 2.1× usualButte, 24 July: 11.6 µg/m³, 1.7× usualButte, 25 July: 7.1 µg/m³, 1.1× usualButte, 26 July: 19.9 µg/m³, 3.0× usualButte, 27 July: 41.5 µg/m³, 6.2× usualButte, 28 July: 32.4 µg/m³, 4.8× usualButte, 29 July: 24.5 µg/m³, 3.7× usualButte, 30 July: 16.0 µg/m³, 2.4× usualButte, 31 July: 15.2 µg/m³, 2.3× usualButte, 1 August: 20.6 µg/m³, 3.1× usualButte, 2 August: 22.3 µg/m³, 3.3× usualButte, 3 August: 30.6 µg/m³, 4.6× usualButte, 4 August: 16.6 µg/m³, 2.5× usualButte, 5 August: 22.9 µg/m³, 3.4× usualButte, 6 August: 30.6 µg/m³, 4.6× usualButte, 7 August: 59.8 µg/m³, 8.9× usualPocatelloPocatello, 17 July: 8.3 µg/m³, 1.4× usualPocatello, 18 July: 8.3 µg/m³, 1.4× usualPocatello, 19 July: 5.8 µg/m³, 1.0× usualPocatello, 20 July: 8.0 µg/m³, 1.3× usualPocatello, 21 July: 13.4 µg/m³, 2.2× usualPocatello, 22 July: 17.0 µg/m³, 2.8× usualPocatello, 23 July: 13.9 µg/m³, 2.3× usualPocatello, 24 July: 6.8 µg/m³, 1.1× usualPocatello, 25 July: 4.1 µg/m³, 0.7× usualPocatello, 26 July: 13.7 µg/m³, 2.2× usualPocatello, 27 July: 59.2 µg/m³, 9.7× usualPocatello, 28 July: 15.8 µg/m³, 2.6× usualPocatello, 29 July: 10.1 µg/m³, 1.7× usualPocatello, 30 July: 6.9 µg/m³, 1.1× usualPocatello, 31 July: 8.8 µg/m³, 1.4× usualPocatello, 1 August: 7.0 µg/m³, 1.1× usualPocatello, 2 August: 49.3 µg/m³, 8.1× usualPocatello, 3 August: 26.8 µg/m³, 4.4× usualPocatello, 4 August: no readingPocatello, 5 August: 21.9 µg/m³, 3.6× usualPocatello, 6 August: 14.0 µg/m³, 2.3× usualPocatello, 7 August: 19.5 µg/m³, 3.2× usualHelenaHelena, 17 July: 4.9 µg/m³, 0.5× usualHelena, 18 July: 4.5 µg/m³, 0.5× usualHelena, 19 July: 7.7 µg/m³, 0.9× usualHelena, 20 July: 9.9 µg/m³, 1.1× usualHelena, 21 July: 13.5 µg/m³, 1.5× usualHelena, 22 July: 12.1 µg/m³, 1.3× usualHelena, 23 July: 12.3 µg/m³, 1.4× usualHelena, 24 July: 10.5 µg/m³, 1.2× usualHelena, 25 July: 8.9 µg/m³, 1.0× usualHelena, 26 July: 22.8 µg/m³, 2.5× usualHelena, 27 July: 41.2 µg/m³, 4.6× usualHelena, 28 July: 30.6 µg/m³, 3.4× usualHelena, 29 July: 26.6 µg/m³, 3.0× usualHelena, 30 July: 17.4 µg/m³, 1.9× usualHelena, 31 July: 16.9 µg/m³, 1.9× usualHelena, 1 August: 18.1 µg/m³, 2.0× usualHelena, 2 August: 20.2 µg/m³, 2.2× usualHelena, 3 August: 18.7 µg/m³, 2.1× usualHelena, 4 August: 15.4 µg/m³, 1.7× usualHelena, 5 August: 20.5 µg/m³, 2.3× usualHelena, 6 August: 39.5 µg/m³, 4.4× usualHelena, 7 August: 35.3 µg/m³, 3.9× usualBillingsBillings, 17 July: 3.8 µg/m³, 0.5× usualBillings, 18 July: 2.6 µg/m³, 0.4× usualBillings, 19 July: 4.6 µg/m³, 0.6× usualBillings, 20 July: 15.7 µg/m³, 2.2× usualBillings, 21 July: 14.5 µg/m³, 2.0× usualBillings, 22 July: 14.7 µg/m³, 2.0× usualBillings, 23 July: 7.1 µg/m³, 1.0× usualBillings, 24 July: 7.5 µg/m³, 1.0× usualBillings, 25 July: 4.2 µg/m³, 0.6× usualBillings, 26 July: 10.6 µg/m³, 1.5× usualBillings, 27 July: 28.1 µg/m³, 3.8× usualBillings, 28 July: 33.5 µg/m³, 4.6× usualBillings, 29 July: 14.8 µg/m³, 2.0× usualBillings, 30 July: 8.1 µg/m³, 1.1× usualBillings, 31 July: 16.1 µg/m³, 2.2× usualBillings, 1 August: 14.8 µg/m³, 2.0× usualBillings, 2 August: 22.9 µg/m³, 3.1× usualBillings, 3 August: 36.6 µg/m³, 5.0× usualBillings, 4 August: 12.9 µg/m³, 1.8× usualBillings, 5 August: 14.2 µg/m³, 1.9× usualBillings, 6 August: 24.9 µg/m³, 3.4× usualBillings, 7 August: 24.8 µg/m³, 3.4× usualLoganLogan, 17 July: 4.5 µg/m³, 0.9× usualLogan, 18 July: 5.1 µg/m³, 1.0× usualLogan, 19 July: 2.0 µg/m³, 0.4× usualLogan, 20 July: 2.8 µg/m³, 0.6× usualLogan, 21 July: 8.1 µg/m³, 1.6× usualLogan, 22 July: 6.0 µg/m³, 1.2× usualLogan, 23 July: 11.8 µg/m³, 2.4× usualLogan, 24 July: 11.5 µg/m³, 2.3× usualLogan, 25 July: 0.7 µg/m³, 0.1× usualLogan, 26 July: 0.0 µg/m³, 0.0× usualLogan, 27 July: 17.0 µg/m³, 3.4× usualLogan, 28 July: 26.7 µg/m³, 5.3× usualLogan, 29 July: 5.0 µg/m³, 1.0× usualLogan, 30 July: 3.6 µg/m³, 0.7× usualLogan, 31 July: 5.9 µg/m³, 1.2× usualLogan, 1 August: 10.5 µg/m³, 2.1× usualLogan, 2 August: 25.7 µg/m³, 5.1× usualLogan, 3 August: 38.4 µg/m³, 7.7× usualLogan, 4 August: 35.2 µg/m³, 7.0× usualLogan, 5 August: 37.8 µg/m³, 7.6× usualLogan, 6 August: 36.1 µg/m³, 7.2× usualLogan, 7 August: 25.0 µg/m³, 5.0× usualMeridianMeridian, 17 July: no readingMeridian, 18 July: no readingMeridian, 19 July: no readingMeridian, 20 July: no readingMeridian, 21 July: no readingMeridian, 22 July: no readingMeridian, 23 July: no readingMeridian, 24 July: no readingMeridian, 25 July: no readingMeridian, 26 July: no readingMeridian, 27 July: no readingMeridian, 28 July: no readingMeridian, 29 July: no readingMeridian, 30 July: no readingMeridian, 31 July: no readingMeridian, 1 August: 36.4 µg/m³, 4.3× usualMeridian, 2 August: 40.4 µg/m³, 4.8× usualMeridian, 3 August: 59.2 µg/m³, 7.0× usualMeridian, 4 August: 58.6 µg/m³, 6.9× usualMeridian, 5 August: 30.1 µg/m³, 3.5× usualMeridian, 6 August: 28.8 µg/m³, 3.4× usualMeridian, 7 August: 58.0 µg/m³, 6.8× usualYakimaYakima, 17 July: 2.3 µg/m³, 0.4× usualYakima, 18 July: 2.5 µg/m³, 0.4× usualYakima, 19 July: 3.8 µg/m³, 0.7× usualYakima, 20 July: 21.5 µg/m³, 3.8× usualYakima, 21 July: 22.2 µg/m³, 3.9× usualYakima, 22 July: 22.7 µg/m³, 4.0× usualYakima, 23 July: 11.1 µg/m³, 1.9× usualYakima, 24 July: 6.6 µg/m³, 1.2× usualYakima, 25 July: 9.3 µg/m³, 1.6× usualYakima, 26 July: 4.2 µg/m³, 0.7× usualYakima, 27 July: 4.0 µg/m³, 0.7× usualYakima, 28 July: 4.9 µg/m³, 0.9× usualYakima, 29 July: 2.1 µg/m³, 0.4× usualYakima, 30 July: 4.4 µg/m³, 0.8× usualYakima, 31 July: 7.0 µg/m³, 1.2× usualYakima, 1 August: 4.1 µg/m³, 0.7× usualYakima, 2 August: 4.3 µg/m³, 0.8× usualYakima, 3 August: 47.5 µg/m³, 8.3× usualYakima, 4 August: 100.0 µg/m³, 18× usualYakima, 5 August: 91.4 µg/m³, 16× usualYakima, 6 August: 57.1 µg/m³, 10× usualYakima, 7 August: 24.6 µg/m³, 4.3× usualPascoPasco, 17 July: no readingPasco, 18 July: no readingPasco, 19 July: no readingPasco, 20 July: no readingPasco, 21 July: no readingPasco, 22 July: no readingPasco, 23 July: no readingPasco, 24 July: no readingPasco, 25 July: no readingPasco, 26 July: no readingPasco, 27 July: no readingPasco, 28 July: no readingPasco, 29 July: no readingPasco, 30 July: no readingPasco, 31 July: no readingPasco, 1 August: no readingPasco, 2 August: no readingPasco, 3 August: 26.7 µg/m³, 5.3× usualPasco, 4 August: 71.3 µg/m³, 14× usualPasco, 5 August: 62.7 µg/m³, 13× usualPasco, 6 August: 63.3 µg/m³, 13× usualPasco, 7 August: 32.3 µg/m³, 6.5× usualBozemanBozeman, 17 July: 5.1 µg/m³, 0.7× usualBozeman, 18 July: 6.4 µg/m³, 0.8× usualBozeman, 19 July: 8.2 µg/m³, 1.1× usualBozeman, 20 July: 12.3 µg/m³, 1.6× usualBozeman, 21 July: 11.3 µg/m³, 1.5× usualBozeman, 22 July: 10.7 µg/m³, 1.4× usualBozeman, 23 July: 9.1 µg/m³, 1.2× usualBozeman, 24 July: 10.7 µg/m³, 1.4× usualBozeman, 25 July: 4.7 µg/m³, 0.6× usualBozeman, 26 July: 7.6 µg/m³, 1.0× usualBozeman, 27 July: 19.6 µg/m³, 2.6× usualBozeman, 28 July: 16.5 µg/m³, 2.2× usualBozeman, 29 July: 11.0 µg/m³, 1.4× usualBozeman, 30 July: 13.0 µg/m³, 1.7× usualBozeman, 31 July: 15.3 µg/m³, 2.0× usualBozeman, 1 August: 10.9 µg/m³, 1.4× usualBozeman, 2 August: 24.4 µg/m³, 3.2× usualBozeman, 3 August: 28.5 µg/m³, 3.8× usualBozeman, 4 August: 12.5 µg/m³, 1.6× usualBozeman, 5 August: 15.4 µg/m³, 2.0× usualBozeman, 6 August: 31.0 µg/m³, 4.1× usualBozeman, 7 August: 44.8 µg/m³, 5.9× usualArvadaArvada, 17 July: 4.8 µg/m³, 0.7× usualArvada, 18 July: 3.8 µg/m³, 0.6× usualArvada, 19 July: 3.4 µg/m³, 0.5× usualArvada, 20 July: 4.1 µg/m³, 0.6× usualArvada, 21 July: 14.6 µg/m³, 2.2× usualArvada, 22 July: 10.0 µg/m³, 1.5× usualArvada, 23 July: 11.5 µg/m³, 1.7× usualArvada, 24 July: 8.5 µg/m³, 1.3× usualArvada, 25 July: 6.5 µg/m³, 1.0× usualArvada, 26 July: 3.2 µg/m³, 0.5× usualArvada, 27 July: 5.0 µg/m³, 0.8× usualArvada, 28 July: 7.4 µg/m³, 1.1× usualArvada, 29 July: 6.4 µg/m³, 1.0× usualArvada, 30 July: 3.9 µg/m³, 0.6× usualArvada, 31 July: 17.1 µg/m³, 2.6× usualArvada, 1 August: 17.6 µg/m³, 2.7× usualArvada, 2 August: 14.0 µg/m³, 2.1× usualArvada, 3 August: 36.1 µg/m³, 5.5× usualArvada, 4 August: 39.6 µg/m³, 6.0× usualArvada, 5 August: 33.8 µg/m³, 5.1× usualArvada, 6 August: 30.6 µg/m³, 4.6× usualArvada, 7 August: 32.0 µg/m³, 4.8× usualWest JordanWest Jordan, 17 July: 7.9 µg/m³, 1.0× usualWest Jordan, 18 July: 6.3 µg/m³, 0.8× usualWest Jordan, 19 July: 6.1 µg/m³, 0.8× usualWest Jordan, 20 July: 5.9 µg/m³, 0.7× usualWest Jordan, 21 July: 9.2 µg/m³, 1.1× usualWest Jordan, 22 July: 7.3 µg/m³, 0.9× usualWest Jordan, 23 July: 6.7 µg/m³, 0.8× usualWest Jordan, 24 July: 8.2 µg/m³, 1.0× usualWest Jordan, 25 July: 8.2 µg/m³, 1.0× usualWest Jordan, 26 July: 9.6 µg/m³, 1.2× usualWest Jordan, 27 July: 14.6 µg/m³, 1.8× usualWest Jordan, 28 July: 21.1 µg/m³, 2.6× usualWest Jordan, 29 July: 15.8 µg/m³, 2.0× usualWest Jordan, 30 July: 12.0 µg/m³, 1.5× usualWest Jordan, 31 July: 15.1 µg/m³, 1.9× usualWest Jordan, 1 August: 14.9 µg/m³, 1.8× usualWest Jordan, 2 August: 17.6 µg/m³, 2.2× usualWest Jordan, 3 August: 35.9 µg/m³, 4.4× usualWest Jordan, 4 August: 24.3 µg/m³, 3.0× usualWest Jordan, 5 August: 26.3 µg/m³, 3.2× usualWest Jordan, 6 August: 19.0 µg/m³, 2.3× usualWest Jordan, 7 August: 14.1 µg/m³, 1.7× usualFort CollinsFort Collins, 17 July: 6.7 µg/m³, 1.0× usualFort Collins, 18 July: 5.7 µg/m³, 0.9× usualFort Collins, 19 July: 5.1 µg/m³, 0.8× usualFort Collins, 20 July: 6.3 µg/m³, 1.0× usualFort Collins, 21 July: 14.8 µg/m³, 2.2× usualFort Collins, 22 July: 9.6 µg/m³, 1.5× usualFort Collins, 23 July: 9.3 µg/m³, 1.4× usualFort Collins, 24 July: 7.8 µg/m³, 1.2× usualFort Collins, 25 July: 7.2 µg/m³, 1.1× usualFort Collins, 26 July: 3.8 µg/m³, 0.6× usualFort Collins, 27 July: 4.7 µg/m³, 0.7× usualFort Collins, 28 July: 5.7 µg/m³, 0.9× usualFort Collins, 29 July: 5.6 µg/m³, 0.8× usualFort Collins, 30 July: 6.8 µg/m³, 1.0× usualFort Collins, 31 July: 13.4 µg/m³, 2.0× usualFort Collins, 1 August: 15.0 µg/m³, 2.3× usualFort Collins, 2 August: 12.2 µg/m³, 1.8× usualFort Collins, 3 August: 35.3 µg/m³, 5.3× usualFort Collins, 4 August: 30.9 µg/m³, 4.7× usualFort Collins, 5 August: 24.5 µg/m³, 3.7× usualFort Collins, 6 August: 22.3 µg/m³, 3.4× usualFort Collins, 7 August: 26.4 µg/m³, 4.0× usualGilletteGillette, 17 July: 8.6 µg/m³, 1.2× usualGillette, 18 July: 7.0 µg/m³, 1.0× usualGillette, 19 July: 5.2 µg/m³, 0.7× usualGillette, 20 July: 12.4 µg/m³, 1.7× usualGillette, 21 July: 13.0 µg/m³, 1.8× usualGillette, 22 July: 12.0 µg/m³, 1.6× usualGillette, 23 July: 8.4 µg/m³, 1.2× usualGillette, 24 July: 6.5 µg/m³, 0.9× usualGillette, 25 July: 4.9 µg/m³, 0.7× usualGillette, 26 July: 5.0 µg/m³, 0.7× usualGillette, 27 July: 3.3 µg/m³, 0.5× usualGillette, 28 July: 7.9 µg/m³, 1.1× usualGillette, 29 July: 4.6 µg/m³, 0.6× usualGillette, 30 July: 6.1 µg/m³, 0.8× usualGillette, 31 July: 6.3 µg/m³, 0.9× usualGillette, 1 August: 8.7 µg/m³, 1.2× usualGillette, 2 August: 11.7 µg/m³, 1.6× usualGillette, 3 August: 35.2 µg/m³, 4.8× usualGillette, 4 August: 17.5 µg/m³, 2.4× usualGillette, 5 August: 15.6 µg/m³, 2.1× usualGillette, 6 August: 20.0 µg/m³, 2.7× usualGillette, 7 August: 18.3 µg/m³, 2.5× usualBoulderBoulder, 17 July: 5.1 µg/m³, 0.8× usualBoulder, 18 July: 4.9 µg/m³, 0.8× usualBoulder, 19 July: 4.4 µg/m³, 0.7× usualBoulder, 20 July: 4.6 µg/m³, 0.7× usualBoulder, 21 July: 11.0 µg/m³, 1.7× usualBoulder, 22 July: 7.2 µg/m³, 1.1× usualBoulder, 23 July: 5.5 µg/m³, 0.9× usualBoulder, 24 July: 6.0 µg/m³, 0.9× usualBoulder, 25 July: 5.3 µg/m³, 0.8× usualBoulder, 26 July: 3.0 µg/m³, 0.5× usualBoulder, 27 July: 4.9 µg/m³, 0.8× usualBoulder, 28 July: 5.1 µg/m³, 0.8× usualBoulder, 29 July: 4.1 µg/m³, 0.6× usualBoulder, 30 July: 3.8 µg/m³, 0.6× usualBoulder, 31 July: 11.0 µg/m³, 1.7× usualBoulder, 1 August: 11.4 µg/m³, 1.8× usualBoulder, 2 August: 11.1 µg/m³, 1.7× usualBoulder, 3 August: 32.3 µg/m³, 5.0× usualBoulder, 4 August: 27.5 µg/m³, 4.3× usualBoulder, 5 August: 22.0 µg/m³, 3.4× usualBoulder, 6 August: 19.4 µg/m³, 3.0× usualBoulder, 7 August: 23.5 µg/m³, 3.7× usualLongmontLongmont, 17 July: 6.3 µg/m³, 0.9× usualLongmont, 18 July: 5.5 µg/m³, 0.8× usualLongmont, 19 July: 5.0 µg/m³, 0.7× usualLongmont, 20 July: 5.4 µg/m³, 0.7× usualLongmont, 21 July: 12.9 µg/m³, 1.8× usualLongmont, 22 July: 8.9 µg/m³, 1.2× usualLongmont, 23 July: 9.9 µg/m³, 1.4× usualLongmont, 24 July: 7.9 µg/m³, 1.1× usualLongmont, 25 July: 6.4 µg/m³, 0.9× usualLongmont, 26 July: 4.0 µg/m³, 0.5× usualLongmont, 27 July: 5.8 µg/m³, 0.8× usualLongmont, 28 July: 6.9 µg/m³, 0.9× usualLongmont, 29 July: 6.6 µg/m³, 0.9× usualLongmont, 30 July: 6.5 µg/m³, 0.9× usualLongmont, 31 July: 13.1 µg/m³, 1.8× usualLongmont, 1 August: 13.8 µg/m³, 1.9× usualLongmont, 2 August: 10.9 µg/m³, 1.5× usualLongmont, 3 August: 31.4 µg/m³, 4.3× usualLongmont, 4 August: 30.0 µg/m³, 4.1× usualLongmont, 5 August: 25.2 µg/m³, 3.5× usualLongmont, 6 August: 23.5 µg/m³, 3.2× usualLongmont, 7 August: 25.2 µg/m³, 3.5× usualSheridanSheridan, 17 July: 10.0 µg/m³, 1.3× usualSheridan, 18 July: 9.8 µg/m³, 1.3× usualSheridan, 19 July: 9.1 µg/m³, 1.2× usualSheridan, 20 July: 15.2 µg/m³, 1.9× usualSheridan, 21 July: 17.0 µg/m³, 2.2× usualSheridan, 22 July: 14.3 µg/m³, 1.8× usualSheridan, 23 July: 11.4 µg/m³, 1.5× usualSheridan, 24 July: 7.8 µg/m³, 1.0× usualSheridan, 25 July: 8.6 µg/m³, 1.1× usualSheridan, 26 July: 5.9 µg/m³, 0.8× usualSheridan, 27 July: 7.9 µg/m³, 1.0× usualSheridan, 28 July: 12.1 µg/m³, 1.6× usualSheridan, 29 July: 10.3 µg/m³, 1.3× usualSheridan, 30 July: 10.4 µg/m³, 1.3× usualSheridan, 31 July: 11.1 µg/m³, 1.4× usualSheridan, 1 August: 11.4 µg/m³, 1.5× usualSheridan, 2 August: 18.8 µg/m³, 2.4× usualSheridan, 3 August: 31.2 µg/m³, 4.0× usualSheridan, 4 August: 19.8 µg/m³, 2.5× usualSheridan, 5 August: 14.9 µg/m³, 1.9× usualSheridan, 6 August: 22.3 µg/m³, 2.9× usualSheridan, 7 August: 29.1 µg/m³, 3.7× usualCañon CityCañon City, 17 July: no readingCañon City, 18 July: 5.8 µg/m³, 1.0× usualCañon City, 19 July: 5.6 µg/m³, 1.0× usualCañon City, 20 July: 5.5 µg/m³, 1.0× usualCañon City, 21 July: 5.9 µg/m³, 1.1× usualCañon City, 22 July: 9.1 µg/m³, 1.6× usualCañon City, 23 July: 3.9 µg/m³, 0.7× usualCañon City, 24 July: 5.4 µg/m³, 1.0× usualCañon City, 25 July: 4.1 µg/m³, 0.7× usualCañon City, 26 July: 3.9 µg/m³, 0.7× usualCañon City, 27 July: 4.4 µg/m³, 0.8× usualCañon City, 28 July: 6.5 µg/m³, 1.2× usualCañon City, 29 July: 5.1 µg/m³, 0.9× usualCañon City, 30 July: 4.5 µg/m³, 0.8× usualCañon City, 31 July: 7.8 µg/m³, 1.4× usualCañon City, 1 August: 9.3 µg/m³, 1.7× usualCañon City, 2 August: 9.0 µg/m³, 1.6× usualCañon City, 3 August: 12.7 µg/m³, 2.3× usualCañon City, 4 August: 33.3 µg/m³, 5.9× usualCañon City, 5 August: 19.7 µg/m³, 3.5× usualCañon City, 6 August: 16.7 µg/m³, 3.0× usualCañon City, 7 August: 15.4 µg/m³, 2.8× usualThorntonThornton, 17 July: 6.7 µg/m³, 0.9× usualThornton, 18 July: 5.6 µg/m³, 0.8× usualThornton, 19 July: 5.0 µg/m³, 0.7× usualThornton, 20 July: 6.7 µg/m³, 0.9× usualThornton, 21 July: 13.2 µg/m³, 1.8× usualThornton, 22 July: 8.2 µg/m³, 1.1× usualThornton, 23 July: 6.5 µg/m³, 0.9× usualThornton, 24 July: 8.1 µg/m³, 1.1× usualThornton, 25 July: 6.2 µg/m³, 0.8× usualThornton, 26 July: 5.1 µg/m³, 0.7× usualThornton, 27 July: 5.9 µg/m³, 0.8× usualThornton, 28 July: 7.0 µg/m³, 0.9× usualThornton, 29 July: 6.2 µg/m³, 0.8× usualThornton, 30 July: 6.8 µg/m³, 0.9× usualThornton, 31 July: 13.6 µg/m³, 1.8× usualThornton, 1 August: 13.6 µg/m³, 1.8× usualThornton, 2 August: 11.0 µg/m³, 1.5× usualThornton, 3 August: 24.4 µg/m³, 3.3× usualThornton, 4 August: 31.8 µg/m³, 4.3× usualThornton, 5 August: 24.1 µg/m³, 3.3× usualThornton, 6 August: 26.5 µg/m³, 3.6× usualThornton, 7 August: 28.0 µg/m³, 3.8× usualColorado SpringsColorado Springs, 17 July: 6.2 µg/m³, 1.0× usualColorado Springs, 18 July: 5.6 µg/m³, 0.9× usualColorado Springs, 19 July: 5.3 µg/m³, 0.8× usualColorado Springs, 20 July: 5.1 µg/m³, 0.8× usualColorado Springs, 21 July: 7.9 µg/m³, 1.3× usualColorado Springs, 22 July: 9.3 µg/m³, 1.5× usualColorado Springs, 23 July: 4.3 µg/m³, 0.7× usualColorado Springs, 24 July: 5.7 µg/m³, 0.9× usualColorado Springs, 25 July: 4.9 µg/m³, 0.8× usualColorado Springs, 26 July: 4.6 µg/m³, 0.7× usualColorado Springs, 27 July: 5.1 µg/m³, 0.8× usualColorado Springs, 28 July: 6.1 µg/m³, 1.0× usualColorado Springs, 29 July: 5.5 µg/m³, 0.9× usualColorado Springs, 30 July: 4.4 µg/m³, 0.7× usualColorado Springs, 31 July: 8.1 µg/m³, 1.3× usualColorado Springs, 1 August: 9.2 µg/m³, 1.5× usualColorado Springs, 2 August: 11.0 µg/m³, 1.7× usualColorado Springs, 3 August: 23.0 µg/m³, 3.7× usualColorado Springs, 4 August: 30.7 µg/m³, 4.9× usualColorado Springs, 5 August: 19.0 µg/m³, 3.0× usualColorado Springs, 6 August: 16.8 µg/m³, 2.7× usualColorado Springs, 7 August: 16.7 µg/m³, 2.7× usualDenverDenver, 17 July: 6.2 µg/m³, 0.9× usualDenver, 18 July: 5.4 µg/m³, 0.8× usualDenver, 19 July: 4.7 µg/m³, 0.7× usualDenver, 20 July: 5.5 µg/m³, 0.8× usualDenver, 21 July: 11.8 µg/m³, 1.8× usualDenver, 22 July: 7.4 µg/m³, 1.1× usualDenver, 23 July: 6.3 µg/m³, 1.0× usualDenver, 24 July: 6.7 µg/m³, 1.0× usualDenver, 25 July: 4.9 µg/m³, 0.7× usualDenver, 26 July: 4.4 µg/m³, 0.7× usualDenver, 27 July: 5.6 µg/m³, 0.8× usualDenver, 28 July: 5.9 µg/m³, 0.9× usualDenver, 29 July: 5.7 µg/m³, 0.9× usualDenver, 30 July: 4.7 µg/m³, 0.7× usualDenver, 31 July: 12.7 µg/m³, 1.9× usualDenver, 1 August: 12.0 µg/m³, 1.8× usualDenver, 2 August: 9.2 µg/m³, 1.4× usualDenver, 3 August: 21.5 µg/m³, 3.3× usualDenver, 4 August: 29.5 µg/m³, 4.5× usualDenver, 5 August: 22.9 µg/m³, 3.5× usualDenver, 6 August: 22.5 µg/m³, 3.4× usualDenver, 7 August: 24.1 µg/m³, 3.7× usualLittletonLittleton, 17 July: no readingLittleton, 18 July: no readingLittleton, 19 July: no readingLittleton, 20 July: no readingLittleton, 21 July: no readingLittleton, 22 July: no readingLittleton, 23 July: no readingLittleton, 24 July: 6.0 µg/m³, 1.2× usualLittleton, 25 July: 4.1 µg/m³, 0.8× usualLittleton, 26 July: 3.8 µg/m³, 0.8× usualLittleton, 27 July: 5.0 µg/m³, 1.0× usualLittleton, 28 July: 5.4 µg/m³, 1.1× usualLittleton, 29 July: 5.1 µg/m³, 1.0× usualLittleton, 30 July: 4.2 µg/m³, 0.8× usualLittleton, 31 July: 10.9 µg/m³, 2.2× usualLittleton, 1 August: 10.0 µg/m³, 2.0× usualLittleton, 2 August: 8.9 µg/m³, 1.8× usualLittleton, 3 August: 19.1 µg/m³, 3.8× usualLittleton, 4 August: 29.1 µg/m³, 5.8× usualLittleton, 5 August: 23.6 µg/m³, 4.7× usualLittleton, 6 August: 19.3 µg/m³, 3.9× usualLittleton, 7 August: 22.8 µg/m³, 4.6× usual17 Jul202326291 Aug47
The 60 cities with the highest readings of 66, in the order the episode reached them, 3 days before to 3 after. Each square is a day, coloured by that day's PM2.5; outlined: at twice the city's usual or more.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

Every city it reached

CityDaysHighestUsualAbove usual
WenatcheeWashington, United States4 204.04 August5.041×
Twin FallsIdaho, United States6 121.027 July6.618×
Walla WallaWashington, United States7 108.05 August6.018×
YakimaWashington, United States1 100.04 August5.718×
KamloopsBritish Columbia, Canada5 191.07 August11.017×
The DallesOregon, United States2 83.86 August4.917×
VernonBritish Columbia, Canada6 122.06 August7.317×
EllensburgWashington, United States2 84.04 August5.515×
Spokane ValleyWashington, United States5 123.017 July8.115×
ChilliwackBritish Columbia, Canada2 81.55 August5.615×
PascoWashington, United States1 71.34 August4.514×
Tri-CitiesWashington, United States4 70.64 August4.714×
PendletonOregon, United States9 86.35 August6.214×
BoiseIdaho, United States13 93.327 July6.814×
NampaIdaho, United States13 119.027 July8.814×
BendOregon, United States3 64.14 August4.413×
KelownaBritish Columbia, Canada2 82.423 July6.712×
RedmondOregon, United States5 79.323 July6.612×
Moses LakeWashington, United States5 85.14 August7.112×
HermistonOregon, United States3 66.16 August5.612×
Idaho FallsIdaho, United States2 71.127 July6.211×
SpokaneWashington, United States6 98.117 July8.611×
Coeur d'AleneIdaho, United States2 97.817 July8.811×
CranbrookBritish Columbia, Canada4 84.27 August7.611×
AirdrieAlberta, Canada8 85.024 July8.011×
Red DeerAlberta, Canada6 99.424 July9.710×
SunnysideWashington, United States2 76.84 August7.510×
AbbotsfordBritish Columbia, Canada2 50.15 August4.610×
PocatelloIdaho, United States3 59.227 July6.19.7×
LethbridgeAlberta, Canada6 86.22 August9.39.3×
ButteMontana, United States3 59.87 August6.78.9×
CalgaryAlberta, Canada9 91.324 July11.38.1×
Sherwood ParkAlberta, Canada4 74.621 July9.38.0×
LoganUtah, United States3 38.43 August4.87.7×
MissoulaMontana, United States7 49.43 August6.77.4×
PullmanWashington, United States8 52.86 August7.57.0×
MeridianIdaho, United States3 59.23 August8.57.0×
St. AlbertAlberta, Canada4 59.821 July9.16.6×
ArvadaColorado, United States2 39.64 August6.66.0×
Cañon CityColorado, United States1 33.34 August5.65.9×
LewistonIdaho, United States11 51.97 August8.85.9×
BozemanMontana, United States1 44.87 August7.65.9×
LittletonColorado, United States1 29.14 August4.55.8×
EdmontonAlberta, Canada4 76.321 July13.25.8×
PuebloColorado, United States1 28.14 August4.95.6×
CasperWyoming, United States1 29.03 August5.35.5×
Swift CurrentSaskatchewan, Canada7 51.624 July9.65.4×
Fort CollinsColorado, United States2 35.33 August6.65.3×
Ken CarylColorado, United States1 28.54 August5.45.3×
Medicine HatAlberta, Canada8 51.32 August9.85.2×
MoscowIdaho, United States5 46.57 August9.25.1×
BoulderColorado, United States2 32.33 August6.45.0×
BillingsMontana, United States3 36.63 August7.35.0×
Colorado SpringsColorado, United States1 30.74 August6.34.9×
GilletteWyoming, United States1 35.23 August7.34.8×
WindsorColorado, United States2 28.84 August6.14.7×
HelenaMontana, United States3 41.227 July9.04.6×
DenverColorado, United States1 29.54 August6.64.5×
West JordanUtah, United States1 35.93 August8.14.4×
LongmontColorado, United States2 31.43 August7.34.3×
ThorntonColorado, United States1 31.84 August7.44.3×
SheridanWyoming, United States1 31.23 August7.84.0×
Great FallsMontana, United States6 48.427 July12.93.8×
GreeleyColorado, United States1 26.04 August7.13.7×
Rapid CitySouth Dakota, United States1 28.73 August9.13.2×
ReginaSaskatchewan, Canada2 35.92 August13.22.7×

Daily means in µg/m³. Usual: the city's median for this time of year (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that.

Against other episodes in the United States and Canada

Number 15 of 106 episodes in the United States and Canada since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 106.

Use this page

SmogRank, North-western United States and Canada, July and August 2026: 66 cities with PM2.5 at twice their usual or more, 20 July to 4 August 2026, smogrank.com/episodes/2026-07-north-western-united-states-and-canada (accessed 2 October 2026).

Download top 10 (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms.

An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes. Values are each city's daily mean of its own monitors; causes are the usual kinds for a pattern like this, not a confirmed source.