SmogRank / Episodes / United States

North-western United States and Canada, August 2023

For 15 days, from 17 to 31 August 2023, 110 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: 597.0 µg/m³ on 21 August, about 55× its usual 10.9.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached110in 2 countries
Days1517 to 31 August 2023
Worst day20 August72 cities counted
Furthest above usual55×Kamloops

Day by day

20 August 72 cities at twice their usual or more
NampaMeridianMissoulaTwin FallsMarysvilleMount VernonOak HarborAnacortesSpanish SpringsPocatelloRenoAberdeenIdaho FallsTruckeeRexburgCarson CityCoos BayParadiseSouth Lake TahoeNorth CowichanCondaBozemanGreat FallsNorth OgdenLincolnRosevilleFolsomTooeleMagnaBountifulSalt Lake CityHerrimanWest JordanMillcreekEurekaDavisHighlandVacavilleOremSpanish ForkConcordLivermoreRichmondSan RafaelClovisSan LeandroFresnoSan FranciscoRedwood CityGilroyCedar CityVisaliaHollisterHanfordSanta CruzPortervilleCorcoranMesquiteHurricaneSalinasSt. AlbertSherwood ParkLas VegasSummerlin SouthSpring ValleyEnterpriseHendersonBoulder CityPrince GeorgeEdmontonRed DeerMaderaBoiseButteMedicine HatAirdrieCalgarySan JoseLethbridgeHelenaYuba CityOaklandMercedArden-ArcadeTurlockRichmondStocktonChicoCampbell RiverLaceyMantecaSanta RosaBellinghamCorvallisDeltaGaltWoodlandTracyVancouverModestoVictoriaDallasHarewoodLongviewNanaimoDuncanMcMinnvilleMilwaukiePort AlberniCourtenayNorth VancouverWoodburnSacramentoPort AngelesStrawberry HillTigardSalemPort CoquitlamLangleyAbbotsfordVancouverAlbanyCentraliaBurnabySeattleLangfordPortlandForest GroveBeavertonSalmon CreekBellevueHillsboroBremertonGreshamUkiahReddingWest VancouverRentonColumbia CityCanbySquamishTacomaOrchardsMoscowEugeneParklandAltamontShorelineLewistonCoquitlamAuburnIssaquahCranbrookRedmondCoeur d'AlenePullmanChilliwackSunnysideYakimaBendVernonEllensburgPendletonMoses LakeSpokane ValleyWenatcheeMedfordSpokaneHermistonAshlandThe DallesKelownaPascoWalla WallaPentictonTri-CitiesRoseburgGrants PassKamloops
14 Aug17202326291 Sep3
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

KamloopsKamloops, 14 August: 24.7 µg/m³, 2.3× usualKamloops, 15 August: 36.9 µg/m³, 3.4× usualKamloops, 16 August: no readingKamloops, 17 August: 81.9 µg/m³, 7.5× usualKamloops, 18 August: 54.9 µg/m³, 5.0× usualKamloops, 19 August: 12.2 µg/m³, 1.1× usualKamloops, 20 August: 131.0 µg/m³, 12× usualKamloops, 21 August: 597.0 µg/m³, 55× usualKamloops, 22 August: 133.0 µg/m³, 12× usualKamloops, 23 August: 25.5 µg/m³, 2.3× usualKamloops, 24 August: 32.7 µg/m³, 3.0× usualKamloops, 25 August: 31.6 µg/m³, 2.9× usualKamloops, 26 August: 30.4 µg/m³, 2.8× usualKamloops, 27 August: 34.4 µg/m³, 3.2× usualKamloops, 28 August: 54.8 µg/m³, 5.0× usualKamloops, 29 August: 83.3 µg/m³, 7.6× usualKamloops, 30 August: 18.7 µg/m³, 1.7× usualKamloops, 31 August: 15.1 µg/m³, 1.4× usualKamloops, 1 September: 13.2 µg/m³, 1.2× usualKamloops, 2 September: 19.5 µg/m³, 1.8× usualKamloops, 3 September: 53.5 µg/m³, 4.9× usualVernonVernon, 14 August: 22.1 µg/m³, 2.3× usualVernon, 15 August: 48.2 µg/m³, 5.0× usualVernon, 16 August: no readingVernon, 17 August: 93.1 µg/m³, 9.6× usualVernon, 18 August: 30.5 µg/m³, 3.1× usualVernon, 19 August: 158.0 µg/m³, 16× usualVernon, 20 August: 201.0 µg/m³, 21× usualVernon, 21 August: 124.0 µg/m³, 13× usualVernon, 22 August: 32.7 µg/m³, 3.4× usualVernon, 23 August: 20.1 µg/m³, 2.1× usualVernon, 24 August: 18.4 µg/m³, 1.9× usualVernon, 25 August: 26.7 µg/m³, 2.8× usualVernon, 26 August: 26.8 µg/m³, 2.8× usualVernon, 27 August: 24.0 µg/m³, 2.5× usualVernon, 28 August: 30.6 µg/m³, 3.2× usualVernon, 29 August: 32.3 µg/m³, 3.3× usualVernon, 30 August: 21.1 µg/m³, 2.2× usualVernon, 31 August: 10.0 µg/m³, 1.0× usualVernon, 1 September: 14.2 µg/m³, 1.5× usualVernon, 2 September: 12.7 µg/m³, 1.3× usualVernon, 3 September: 15.8 µg/m³, 1.6× usualRedmondRedmond, 14 August: 8.5 µg/m³, 0.8× usualRedmond, 15 August: 80.7 µg/m³, 7.2× usualRedmond, 16 August: 143.0 µg/m³, 13× usualRedmond, 17 August: 50.3 µg/m³, 4.5× usualRedmond, 18 August: 105.0 µg/m³, 9.4× usualRedmond, 19 August: 50.2 µg/m³, 4.5× usualRedmond, 20 August: 155.0 µg/m³, 14× usualRedmond, 21 August: 157.0 µg/m³, 14× usualRedmond, 22 August: 145.0 µg/m³, 13× usualRedmond, 23 August: 63.5 µg/m³, 5.7× usualRedmond, 24 August: 19.4 µg/m³, 1.7× usualRedmond, 25 August: 15.4 µg/m³, 1.4× usualRedmond, 26 August: 15.6 µg/m³, 1.4× usualRedmond, 27 August: 38.5 µg/m³, 3.4× usualRedmond, 28 August: 119.0 µg/m³, 11× usualRedmond, 29 August: 58.1 µg/m³, 5.2× usualRedmond, 30 August: 27.7 µg/m³, 2.5× usualRedmond, 31 August: 33.7 µg/m³, 3.0× usualRedmond, 1 September: 13.5 µg/m³, 1.2× usualRedmond, 2 September: 6.9 µg/m³, 0.6× usualRedmond, 3 September: 7.9 µg/m³, 0.7× usualBendBend, 14 August: 6.0 µg/m³, 0.8× usualBend, 15 August: 31.3 µg/m³, 4.2× usualBend, 16 August: 109.5 µg/m³, 15× usualBend, 17 August: 47.6 µg/m³, 6.3× usualBend, 18 August: 102.0 µg/m³, 14× usualBend, 19 August: 39.2 µg/m³, 5.2× usualBend, 20 August: 116.5 µg/m³, 16× usualBend, 21 August: 107.5 µg/m³, 14× usualBend, 22 August: 47.1 µg/m³, 6.3× usualBend, 23 August: 39.9 µg/m³, 5.3× usualBend, 24 August: 18.3 µg/m³, 2.4× usualBend, 25 August: 10.0 µg/m³, 1.3× usualBend, 26 August: 19.1 µg/m³, 2.5× usualBend, 27 August: 85.7 µg/m³, 11× usualBend, 28 August: 154.5 µg/m³, 21× usualBend, 29 August: 57.8 µg/m³, 7.7× usualBend, 30 August: 29.0 µg/m³, 3.9× usualBend, 31 August: 43.0 µg/m³, 5.7× usualBend, 1 September: 9.9 µg/m³, 1.3× usualBend, 2 September: 4.0 µg/m³, 0.5× usualBend, 3 September: 5.1 µg/m³, 0.7× usualEugeneEugene, 14 August: 12.8 µg/m³, 2.4× usualEugene, 15 August: 59.6 µg/m³, 11× usualEugene, 16 August: 21.2 µg/m³, 3.9× usualEugene, 17 August: 11.2 µg/m³, 2.1× usualEugene, 18 August: 4.9 µg/m³, 0.9× usualEugene, 19 August: 5.4 µg/m³, 1.0× usualEugene, 20 August: 53.6 µg/m³, 9.9× usualEugene, 21 August: 27.2 µg/m³, 5.0× usualEugene, 22 August: 3.4 µg/m³, 0.6× usualEugene, 23 August: 7.5 µg/m³, 1.4× usualEugene, 24 August: 21.6 µg/m³, 4.0× usualEugene, 25 August: 58.7 µg/m³, 11× usualEugene, 26 August: 34.2 µg/m³, 6.3× usualEugene, 27 August: 24.1 µg/m³, 4.5× usualEugene, 28 August: 20.9 µg/m³, 3.9× usualEugene, 29 August: 11.6 µg/m³, 2.1× usualEugene, 30 August: 8.3 µg/m³, 1.5× usualEugene, 31 August: 16.5 µg/m³, 3.1× usualEugene, 1 September: 10.3 µg/m³, 1.9× usualEugene, 2 September: 15.0 µg/m³, 2.8× usualEugene, 3 September: 5.5 µg/m³, 1.0× usualMoscowMoscow, 14 August: 8.4 µg/m³, 0.8× usualMoscow, 15 August: 10.3 µg/m³, 1.0× usualMoscow, 16 August: 26.3 µg/m³, 2.6× usualMoscow, 17 August: 25.3 µg/m³, 2.5× usualMoscow, 18 August: 9.3 µg/m³, 0.9× usualMoscow, 19 August: 45.3 µg/m³, 4.4× usualMoscow, 20 August: 106.0 µg/m³, 10× usualMoscow, 21 August: 6.2 µg/m³, 0.6× usualMoscow, 22 August: 25.6 µg/m³, 2.5× usualMoscow, 23 August: 17.4 µg/m³, 1.7× usualMoscow, 24 August: 17.0 µg/m³, 1.7× usualMoscow, 25 August: 19.2 µg/m³, 1.9× usualMoscow, 26 August: 8.0 µg/m³, 0.8× usualMoscow, 27 August: 6.9 µg/m³, 0.7× usualMoscow, 28 August: 8.5 µg/m³, 0.8× usualMoscow, 29 August: 12.7 µg/m³, 1.2× usualMoscow, 30 August: 3.0 µg/m³, 0.3× usualMoscow, 31 August: 3.7 µg/m³, 0.4× usualMoscow, 1 September: 4.4 µg/m³, 0.4× usualMoscow, 2 September: 5.3 µg/m³, 0.5× usualMoscow, 3 September: 6.3 µg/m³, 0.6× usualAltamontAltamont, 14 August: 5.8 µg/m³, 1.0× usualAltamont, 15 August: 13.5 µg/m³, 2.4× usualAltamont, 16 August: 25.6 µg/m³, 4.6× usualAltamont, 17 August: 9.2 µg/m³, 1.6× usualAltamont, 18 August: 39.7 µg/m³, 7.1× usualAltamont, 19 August: 33.4 µg/m³, 6.0× usualAltamont, 20 August: 15.2 µg/m³, 2.7× usualAltamont, 21 August: 4.3 µg/m³, 0.8× usualAltamont, 22 August: 35.0 µg/m³, 6.3× usualAltamont, 23 August: 58.6 µg/m³, 10× usualAltamont, 24 August: 30.2 µg/m³, 5.4× usualAltamont, 25 August: 40.5 µg/m³, 7.2× usualAltamont, 26 August: 12.8 µg/m³, 2.3× usualAltamont, 27 August: 20.5 µg/m³, 3.7× usualAltamont, 28 August: 63.2 µg/m³, 11× usualAltamont, 29 August: 60.8 µg/m³, 11× usualAltamont, 30 August: 13.3 µg/m³, 2.4× usualAltamont, 31 August: 24.4 µg/m³, 4.4× usualAltamont, 1 September: 23.5 µg/m³, 4.2× usualAltamont, 2 September: 3.9 µg/m³, 0.7× usualAltamont, 3 September: 4.2 µg/m³, 0.8× usualHelenaHelena, 14 August: 7.4 µg/m³, 0.8× usualHelena, 15 August: 8.8 µg/m³, 0.9× usualHelena, 16 August: 28.5 µg/m³, 3.0× usualHelena, 17 August: 41.1 µg/m³, 4.3× usualHelena, 18 August: 20.4 µg/m³, 2.1× usualHelena, 19 August: 17.3 µg/m³, 1.8× usualHelena, 20 August: 11.7 µg/m³, 1.2× usualHelena, 21 August: 4.5 µg/m³, 0.5× usualHelena, 22 August: 5.0 µg/m³, 0.5× usualHelena, 23 August: 7.2 µg/m³, 0.8× usualHelena, 24 August: 20.1 µg/m³, 2.1× usualHelena, 25 August: 11.9 µg/m³, 1.2× usualHelena, 26 August: 8.5 µg/m³, 0.9× usualHelena, 27 August: 12.7 µg/m³, 1.3× usualHelena, 28 August: 8.9 µg/m³, 0.9× usualHelena, 29 August: 6.4 µg/m³, 0.7× usualHelena, 30 August: 4.8 µg/m³, 0.5× usualHelena, 31 August: 5.0 µg/m³, 0.5× usualHelena, 1 September: 11.3 µg/m³, 1.2× usualHelena, 2 September: 13.3 µg/m³, 1.4× usualHelena, 3 September: 6.6 µg/m³, 0.7× usualKelownaKelowna, 14 August: 15.6 µg/m³, 1.8× usualKelowna, 15 August: no readingKelowna, 16 August: no readingKelowna, 17 August: 52.8 µg/m³, 5.9× usualKelowna, 18 August: 56.1 µg/m³, 6.3× usualKelowna, 19 August: 201.0 µg/m³, 23× usualKelowna, 20 August: 267.0 µg/m³, 30× usualKelowna, 21 August: 168.0 µg/m³, 19× usualKelowna, 22 August: 46.9 µg/m³, 5.3× usualKelowna, 23 August: 5.1 µg/m³, 0.6× usualKelowna, 24 August: 15.2 µg/m³, 1.7× usualKelowna, 25 August: 23.3 µg/m³, 2.6× usualKelowna, 26 August: 31.4 µg/m³, 3.5× usualKelowna, 27 August: 25.7 µg/m³, 2.9× usualKelowna, 28 August: 31.1 µg/m³, 3.5× usualKelowna, 29 August: 30.3 µg/m³, 3.4× usualKelowna, 30 August: 7.2 µg/m³, 0.8× usualKelowna, 31 August: 12.9 µg/m³, 1.4× usualKelowna, 1 September: 20.5 µg/m³, 2.3× usualKelowna, 2 September: 16.9 µg/m³, 1.9× usualKelowna, 3 September: 8.1 µg/m³, 0.9× usualPentictonPenticton, 14 August: 10.6 µg/m³, 1.5× usualPenticton, 15 August: 23.6 µg/m³, 3.4× usualPenticton, 16 August: no readingPenticton, 17 August: 92.8 µg/m³, 13× usualPenticton, 18 August: 39.5 µg/m³, 5.6× usualPenticton, 19 August: 113.0 µg/m³, 16× usualPenticton, 20 August: 251.0 µg/m³, 36× usualPenticton, 21 August: 210.0 µg/m³, 30× usualPenticton, 22 August: 82.9 µg/m³, 12× usualPenticton, 23 August: 11.5 µg/m³, 1.6× usualPenticton, 24 August: 21.4 µg/m³, 3.1× usualPenticton, 25 August: 31.6 µg/m³, 4.5× usualPenticton, 26 August: 28.0 µg/m³, 4.0× usualPenticton, 27 August: 31.6 µg/m³, 4.5× usualPenticton, 28 August: 39.0 µg/m³, 5.6× usualPenticton, 29 August: 32.8 µg/m³, 4.7× usualPenticton, 30 August: 4.5 µg/m³, 0.6× usualPenticton, 31 August: 11.3 µg/m³, 1.6× usualPenticton, 1 September: 17.9 µg/m³, 2.6× usualPenticton, 2 September: 14.7 µg/m³, 2.1× usualPenticton, 3 September: 7.0 µg/m³, 1.0× usualGrants PassGrants Pass, 14 August: 11.1 µg/m³, 2.2× usualGrants Pass, 15 August: 11.7 µg/m³, 2.3× usualGrants Pass, 16 August: 16.1 µg/m³, 3.2× usualGrants Pass, 17 August: 50.5 µg/m³, 10× usualGrants Pass, 18 August: 6.4 µg/m³, 1.3× usualGrants Pass, 19 August: 31.8 µg/m³, 6.4× usualGrants Pass, 20 August: 56.1 µg/m³, 11× usualGrants Pass, 21 August: 113.0 µg/m³, 23× usualGrants Pass, 22 August: 53.7 µg/m³, 11× usualGrants Pass, 23 August: 14.1 µg/m³, 2.8× usualGrants Pass, 24 August: 77.9 µg/m³, 16× usualGrants Pass, 25 August: 175.0 µg/m³, 35× usualGrants Pass, 26 August: 112.0 µg/m³, 22× usualGrants Pass, 27 August: 214.0 µg/m³, 43× usualGrants Pass, 28 August: 211.0 µg/m³, 42× usualGrants Pass, 29 August: 39.1 µg/m³, 7.8× usualGrants Pass, 30 August: 50.0 µg/m³, 10× usualGrants Pass, 31 August: 63.2 µg/m³, 13× usualGrants Pass, 1 September: 10.2 µg/m³, 2.0× usualGrants Pass, 2 September: 10.6 µg/m³, 2.1× usualGrants Pass, 3 September: 10.6 µg/m³, 2.1× usualEdmontonEdmonton, 14 August: 10.5 µg/m³, 0.8× usualEdmonton, 15 August: 19.8 µg/m³, 1.5× usualEdmonton, 16 August: 13.5 µg/m³, 1.0× usualEdmonton, 17 August: 29.1 µg/m³, 2.2× usualEdmonton, 18 August: 25.6 µg/m³, 1.9× usualEdmonton, 19 August: 14.4 µg/m³, 1.1× usualEdmonton, 20 August: 13.2 µg/m³, 1.0× usualEdmonton, 21 August: 22.3 µg/m³, 1.7× usualEdmonton, 22 August: 26.3 µg/m³, 2.0× usualEdmonton, 23 August: 11.5 µg/m³, 0.9× usualEdmonton, 24 August: 46.6 µg/m³, 3.5× usualEdmonton, 25 August: 79.4 µg/m³, 6.0× usualEdmonton, 26 August: 25.5 µg/m³, 1.9× usualEdmonton, 27 August: 56.6 µg/m³, 4.3× usualEdmonton, 28 August: 61.9 µg/m³, 4.7× usualEdmonton, 29 August: 46.6 µg/m³, 3.5× usualEdmonton, 30 August: 47.0 µg/m³, 3.6× usualEdmonton, 31 August: 51.9 µg/m³, 3.9× usualEdmonton, 1 September: 76.3 µg/m³, 5.8× usualEdmonton, 2 September: 121.0 µg/m³, 9.2× usualEdmonton, 3 September: 201.0 µg/m³, 15× usualMoses LakeMoses Lake, 14 August: 6.8 µg/m³, 0.9× usualMoses Lake, 15 August: 7.2 µg/m³, 0.9× usualMoses Lake, 16 August: 24.7 µg/m³, 3.3× usualMoses Lake, 17 August: 37.2 µg/m³, 4.9× usualMoses Lake, 18 August: 7.1 µg/m³, 0.9× usualMoses Lake, 19 August: 140.0 µg/m³, 18× usualMoses Lake, 20 August: 192.0 µg/m³, 25× usualMoses Lake, 21 August: 154.0 µg/m³, 20× usualMoses Lake, 22 August: 42.6 µg/m³, 5.6× usualMoses Lake, 23 August: 10.7 µg/m³, 1.4× usualMoses Lake, 24 August: 10.4 µg/m³, 1.4× usualMoses Lake, 25 August: 15.6 µg/m³, 2.1× usualMoses Lake, 26 August: 14.3 µg/m³, 1.9× usualMoses Lake, 27 August: 17.8 µg/m³, 2.3× usualMoses Lake, 28 August: 16.1 µg/m³, 2.1× usualMoses Lake, 29 August: 18.0 µg/m³, 2.4× usualMoses Lake, 30 August: 8.0 µg/m³, 1.1× usualMoses Lake, 31 August: 4.3 µg/m³, 0.6× usualMoses Lake, 1 September: 7.1 µg/m³, 0.9× usualMoses Lake, 2 September: 8.3 µg/m³, 1.1× usualMoses Lake, 3 September: 7.1 µg/m³, 0.9× usualMedfordMedford, 14 August: 10.3 µg/m³, 1.8× usualMedford, 15 August: 14.9 µg/m³, 2.6× usualMedford, 16 August: 18.4 µg/m³, 3.2× usualMedford, 17 August: 94.7 µg/m³, 16× usualMedford, 18 August: 78.3 µg/m³, 14× usualMedford, 19 August: 28.3 µg/m³, 4.9× usualMedford, 20 August: 47.8 µg/m³, 8.2× usualMedford, 21 August: 71.1 µg/m³, 12× usualMedford, 22 August: 131.0 µg/m³, 23× usualMedford, 23 August: 61.1 µg/m³, 11× usualMedford, 24 August: 72.2 µg/m³, 12× usualMedford, 25 August: 138.0 µg/m³, 24× usualMedford, 26 August: 86.1 µg/m³, 15× usualMedford, 27 August: 139.0 µg/m³, 24× usualMedford, 28 August: 160.0 µg/m³, 28× usualMedford, 29 August: 62.4 µg/m³, 11× usualMedford, 30 August: 31.6 µg/m³, 5.4× usualMedford, 31 August: 28.0 µg/m³, 4.8× usualMedford, 1 September: 15.3 µg/m³, 2.6× usualMedford, 2 September: 7.5 µg/m³, 1.3× usualMedford, 3 September: 9.0 µg/m³, 1.6× usualAshlandAshland, 14 August: 9.4 µg/m³, 1.8× usualAshland, 15 August: 14.6 µg/m³, 2.9× usualAshland, 16 August: 16.9 µg/m³, 3.3× usualAshland, 17 August: 130.5 µg/m³, 26× usualAshland, 18 August: 102.6 µg/m³, 20× usualAshland, 19 August: 28.8 µg/m³, 5.6× usualAshland, 20 August: 54.5 µg/m³, 11× usualAshland, 21 August: 43.0 µg/m³, 8.4× usualAshland, 22 August: 146.5 µg/m³, 29× usualAshland, 23 August: 72.1 µg/m³, 14× usualAshland, 24 August: 72.4 µg/m³, 14× usualAshland, 25 August: 141.5 µg/m³, 28× usualAshland, 26 August: 71.4 µg/m³, 14× usualAshland, 27 August: 128.0 µg/m³, 25× usualAshland, 28 August: 149.0 µg/m³, 29× usualAshland, 29 August: 64.3 µg/m³, 13× usualAshland, 30 August: 32.5 µg/m³, 6.4× usualAshland, 31 August: 29.3 µg/m³, 5.7× usualAshland, 1 September: 13.6 µg/m³, 2.7× usualAshland, 2 September: 6.0 µg/m³, 1.2× usualAshland, 3 September: 8.7 µg/m³, 1.7× usualLewistonLewiston, 14 August: 8.5 µg/m³, 0.8× usualLewiston, 15 August: 10.6 µg/m³, 1.0× usualLewiston, 16 August: 12.6 µg/m³, 1.2× usualLewiston, 17 August: 27.0 µg/m³, 2.5× usualLewiston, 18 August: 12.1 µg/m³, 1.1× usualLewiston, 19 August: 27.3 µg/m³, 2.6× usualLewiston, 20 August: 123.0 µg/m³, 12× usualLewiston, 21 August: 55.0 µg/m³, 5.2× usualLewiston, 22 August: 38.1 µg/m³, 3.6× usualLewiston, 23 August: 35.8 µg/m³, 3.4× usualLewiston, 24 August: 20.5 µg/m³, 1.9× usualLewiston, 25 August: 25.8 µg/m³, 2.4× usualLewiston, 26 August: 15.9 µg/m³, 1.5× usualLewiston, 27 August: 6.2 µg/m³, 0.6× usualLewiston, 28 August: 10.1 µg/m³, 1.0× usualLewiston, 29 August: 14.4 µg/m³, 1.4× usualLewiston, 30 August: 6.8 µg/m³, 0.6× usualLewiston, 31 August: 4.5 µg/m³, 0.4× usualLewiston, 1 September: 4.6 µg/m³, 0.4× usualLewiston, 2 September: 6.6 µg/m³, 0.6× usualLewiston, 3 September: 6.6 µg/m³, 0.6× usualRed DeerRed Deer, 14 August: 8.5 µg/m³, 0.8× usualRed Deer, 15 August: 19.7 µg/m³, 1.8× usualRed Deer, 16 August: 14.4 µg/m³, 1.3× usualRed Deer, 17 August: 28.6 µg/m³, 2.6× usualRed Deer, 18 August: 19.1 µg/m³, 1.7× usualRed Deer, 19 August: 6.0 µg/m³, 0.5× usualRed Deer, 20 August: 16.8 µg/m³, 1.5× usualRed Deer, 21 August: 18.4 µg/m³, 1.7× usualRed Deer, 22 August: 16.2 µg/m³, 1.5× usualRed Deer, 23 August: 6.6 µg/m³, 0.6× usualRed Deer, 24 August: 14.8 µg/m³, 1.3× usualRed Deer, 25 August: 25.9 µg/m³, 2.4× usualRed Deer, 26 August: 15.1 µg/m³, 1.4× usualRed Deer, 27 August: 29.8 µg/m³, 2.7× usualRed Deer, 28 August: 33.7 µg/m³, 3.1× usualRed Deer, 29 August: 28.6 µg/m³, 2.6× usualRed Deer, 30 August: 27.5 µg/m³, 2.5× usualRed Deer, 31 August: 44.0 µg/m³, 4.0× usualRed Deer, 1 September: 40.3 µg/m³, 3.7× usualRed Deer, 2 September: 49.0 µg/m³, 4.5× usualRed Deer, 3 September: 111.7 µg/m³, 10× usualCranbrookCranbrook, 14 August: 7.6 µg/m³, 0.9× usualCranbrook, 15 August: 12.2 µg/m³, 1.5× usualCranbrook, 16 August: no readingCranbrook, 17 August: 104.0 µg/m³, 12× usualCranbrook, 18 August: 38.4 µg/m³, 4.6× usualCranbrook, 19 August: 101.0 µg/m³, 12× usualCranbrook, 20 August: 58.1 µg/m³, 6.9× usualCranbrook, 21 August: 54.5 µg/m³, 6.5× usualCranbrook, 22 August: 11.2 µg/m³, 1.3× usualCranbrook, 23 August: 23.5 µg/m³, 2.8× usualCranbrook, 24 August: 7.2 µg/m³, 0.9× usualCranbrook, 25 August: 14.0 µg/m³, 1.7× usualCranbrook, 26 August: 10.4 µg/m³, 1.2× usualCranbrook, 27 August: 16.3 µg/m³, 1.9× usualCranbrook, 28 August: 17.9 µg/m³, 2.1× usualCranbrook, 29 August: 15.8 µg/m³, 1.9× usualCranbrook, 30 August: 2.5 µg/m³, 0.3× usualCranbrook, 31 August: 7.0 µg/m³, 0.8× usualCranbrook, 1 September: 6.6 µg/m³, 0.8× usualCranbrook, 2 September: 6.2 µg/m³, 0.7× usualCranbrook, 3 September: 7.0 µg/m³, 0.8× usualCalgaryCalgary, 14 August: 8.4 µg/m³, 0.7× usualCalgary, 15 August: 15.1 µg/m³, 1.2× usualCalgary, 16 August: 25.1 µg/m³, 2.0× usualCalgary, 17 August: 49.2 µg/m³, 3.9× usualCalgary, 18 August: 19.8 µg/m³, 1.6× usualCalgary, 19 August: 20.6 µg/m³, 1.6× usualCalgary, 20 August: 35.0 µg/m³, 2.8× usualCalgary, 21 August: 18.7 µg/m³, 1.5× usualCalgary, 22 August: 11.7 µg/m³, 0.9× usualCalgary, 23 August: 12.5 µg/m³, 1.0× usualCalgary, 24 August: 21.1 µg/m³, 1.7× usualCalgary, 25 August: 17.5 µg/m³, 1.4× usualCalgary, 26 August: 16.9 µg/m³, 1.3× usualCalgary, 27 August: 21.4 µg/m³, 1.7× usualCalgary, 28 August: 23.2 µg/m³, 1.8× usualCalgary, 29 August: 22.0 µg/m³, 1.7× usualCalgary, 30 August: 25.0 µg/m³, 2.0× usualCalgary, 31 August: 42.6 µg/m³, 3.4× usualCalgary, 1 September: 23.7 µg/m³, 1.9× usualCalgary, 2 September: 10.7 µg/m³, 0.8× usualCalgary, 3 September: 62.7 µg/m³, 5.0× usualAirdrieAirdrie, 14 August: 8.4 µg/m³, 0.9× usualAirdrie, 15 August: 10.5 µg/m³, 1.2× usualAirdrie, 16 August: 19.1 µg/m³, 2.1× usualAirdrie, 17 August: 34.3 µg/m³, 3.8× usualAirdrie, 18 August: 9.8 µg/m³, 1.1× usualAirdrie, 19 August: 7.8 µg/m³, 0.9× usualAirdrie, 20 August: 23.3 µg/m³, 2.6× usualAirdrie, 21 August: 9.5 µg/m³, 1.1× usualAirdrie, 22 August: 7.2 µg/m³, 0.8× usualAirdrie, 23 August: 11.2 µg/m³, 1.2× usualAirdrie, 24 August: 18.2 µg/m³, 2.0× usualAirdrie, 25 August: 12.9 µg/m³, 1.4× usualAirdrie, 26 August: 13.6 µg/m³, 1.5× usualAirdrie, 27 August: 17.9 µg/m³, 2.0× usualAirdrie, 28 August: 17.4 µg/m³, 1.9× usualAirdrie, 29 August: 17.4 µg/m³, 1.9× usualAirdrie, 30 August: 17.8 µg/m³, 2.0× usualAirdrie, 31 August: 30.5 µg/m³, 3.4× usualAirdrie, 1 September: 17.3 µg/m³, 1.9× usualAirdrie, 2 September: 6.5 µg/m³, 0.7× usualAirdrie, 3 September: 58.5 µg/m³, 6.5× usualLethbridgeLethbridge, 14 August: 9.9 µg/m³, 1.1× usualLethbridge, 15 August: 15.2 µg/m³, 1.6× usualLethbridge, 16 August: 17.4 µg/m³, 1.9× usualLethbridge, 17 August: 39.8 µg/m³, 4.3× usualLethbridge, 18 August: 18.1 µg/m³, 1.9× usualLethbridge, 19 August: 7.0 µg/m³, 0.8× usualLethbridge, 20 August: 16.4 µg/m³, 1.8× usualLethbridge, 21 August: 12.1 µg/m³, 1.3× usualLethbridge, 22 August: 5.1 µg/m³, 0.5× usualLethbridge, 23 August: 13.9 µg/m³, 1.5× usualLethbridge, 24 August: 5.0 µg/m³, 0.5× usualLethbridge, 25 August: 11.5 µg/m³, 1.2× usualLethbridge, 26 August: 8.5 µg/m³, 0.9× usualLethbridge, 27 August: 13.0 µg/m³, 1.4× usualLethbridge, 28 August: 12.3 µg/m³, 1.3× usualLethbridge, 29 August: 14.0 µg/m³, 1.5× usualLethbridge, 30 August: 4.5 µg/m³, 0.5× usualLethbridge, 31 August: 25.8 µg/m³, 2.8× usualLethbridge, 1 September: 14.1 µg/m³, 1.5× usualLethbridge, 2 September: 3.4 µg/m³, 0.4× usualLethbridge, 3 September: 18.1 µg/m³, 1.9× usualSpokaneSpokane, 14 August: 9.2 µg/m³, 1.0× usualSpokane, 15 August: 11.8 µg/m³, 1.3× usualSpokane, 16 August: 14.9 µg/m³, 1.6× usualSpokane, 17 August: 22.3 µg/m³, 2.4× usualSpokane, 18 August: 26.9 µg/m³, 2.9× usualSpokane, 19 August: 256.0 µg/m³, 28× usualSpokane, 20 August: 201.0 µg/m³, 22× usualSpokane, 21 August: 63.1 µg/m³, 6.9× usualSpokane, 22 August: 25.0 µg/m³, 2.7× usualSpokane, 23 August: 12.0 µg/m³, 1.3× usualSpokane, 24 August: 10.5 µg/m³, 1.1× usualSpokane, 25 August: 13.8 µg/m³, 1.5× usualSpokane, 26 August: 17.0 µg/m³, 1.8× usualSpokane, 27 August: 17.5 µg/m³, 1.9× usualSpokane, 28 August: 18.4 µg/m³, 2.0× usualSpokane, 29 August: 14.7 µg/m³, 1.6× usualSpokane, 30 August: 6.2 µg/m³, 0.7× usualSpokane, 31 August: 4.1 µg/m³, 0.4× usualSpokane, 1 September: 5.1 µg/m³, 0.6× usualSpokane, 2 September: 5.9 µg/m³, 0.6× usualSpokane, 3 September: 5.1 µg/m³, 0.6× usualSpokane ValleySpokane Valley, 14 August: 8.7 µg/m³, 1.0× usualSpokane Valley, 15 August: 10.3 µg/m³, 1.1× usualSpokane Valley, 16 August: 15.9 µg/m³, 1.8× usualSpokane Valley, 17 August: 21.8 µg/m³, 2.4× usualSpokane Valley, 18 August: 30.0 µg/m³, 3.3× usualSpokane Valley, 19 August: 237.0 µg/m³, 26× usualSpokane Valley, 20 August: 175.0 µg/m³, 19× usualSpokane Valley, 21 August: 39.0 µg/m³, 4.3× usualSpokane Valley, 22 August: 23.7 µg/m³, 2.6× usualSpokane Valley, 23 August: 10.2 µg/m³, 1.1× usualSpokane Valley, 24 August: 7.5 µg/m³, 0.8× usualSpokane Valley, 25 August: 13.1 µg/m³, 1.5× usualSpokane Valley, 26 August: 14.7 µg/m³, 1.6× usualSpokane Valley, 27 August: 14.3 µg/m³, 1.6× usualSpokane Valley, 28 August: 16.7 µg/m³, 1.9× usualSpokane Valley, 29 August: 14.8 µg/m³, 1.6× usualSpokane Valley, 30 August: 3.8 µg/m³, 0.4× usualSpokane Valley, 31 August: 2.9 µg/m³, 0.3× usualSpokane Valley, 1 September: 4.3 µg/m³, 0.5× usualSpokane Valley, 2 September: 6.3 µg/m³, 0.7× usualSpokane Valley, 3 September: 4.6 µg/m³, 0.5× usualWalla WallaWalla Walla, 14 August: 7.0 µg/m³, 1.0× usualWalla Walla, 15 August: 8.0 µg/m³, 1.1× usualWalla Walla, 16 August: 8.1 µg/m³, 1.2× usualWalla Walla, 17 August: 10.1 µg/m³, 1.4× usualWalla Walla, 18 August: 5.7 µg/m³, 0.8× usualWalla Walla, 19 August: 71.9 µg/m³, 10× usualWalla Walla, 20 August: 226.0 µg/m³, 32× usualWalla Walla, 21 August: 196.0 µg/m³, 28× usualWalla Walla, 22 August: 25.1 µg/m³, 3.6× usualWalla Walla, 23 August: 10.6 µg/m³, 1.5× usualWalla Walla, 24 August: 18.1 µg/m³, 2.6× usualWalla Walla, 25 August: 15.4 µg/m³, 2.2× usualWalla Walla, 26 August: 16.4 µg/m³, 2.3× usualWalla Walla, 27 August: 11.8 µg/m³, 1.7× usualWalla Walla, 28 August: 10.0 µg/m³, 1.4× usualWalla Walla, 29 August: no readingWalla Walla, 30 August: no readingWalla Walla, 31 August: 4.1 µg/m³, 0.6× usualWalla Walla, 1 September: 4.5 µg/m³, 0.6× usualWalla Walla, 2 September: 8.2 µg/m³, 1.2× usualWalla Walla, 3 September: 5.7 µg/m³, 0.8× usualTri-CitiesTri-Cities, 14 August: 4.6 µg/m³, 0.8× usualTri-Cities, 15 August: 5.3 µg/m³, 0.9× usualTri-Cities, 16 August: 11.0 µg/m³, 1.9× usualTri-Cities, 17 August: 11.7 µg/m³, 2.0× usualTri-Cities, 18 August: 3.3 µg/m³, 0.6× usualTri-Cities, 19 August: 107.0 µg/m³, 18× usualTri-Cities, 20 August: 193.5 µg/m³, 33× usualTri-Cities, 21 August: 211.5 µg/m³, 36× usualTri-Cities, 22 August: 24.8 µg/m³, 4.3× usualTri-Cities, 23 August: 4.8 µg/m³, 0.8× usualTri-Cities, 24 August: 10.0 µg/m³, 1.7× usualTri-Cities, 25 August: 12.4 µg/m³, 2.1× usualTri-Cities, 26 August: 12.6 µg/m³, 2.2× usualTri-Cities, 27 August: 10.1 µg/m³, 1.7× usualTri-Cities, 28 August: 12.6 µg/m³, 2.2× usualTri-Cities, 29 August: 8.0 µg/m³, 1.4× usualTri-Cities, 30 August: 2.1 µg/m³, 0.4× usualTri-Cities, 31 August: 3.2 µg/m³, 0.6× usualTri-Cities, 1 September: 3.9 µg/m³, 0.7× usualTri-Cities, 2 September: 6.9 µg/m³, 1.2× usualTri-Cities, 3 September: 4.8 µg/m³, 0.8× usualHermistonHermiston, 14 August: 9.0 µg/m³, 1.3× usualHermiston, 15 August: 10.6 µg/m³, 1.5× usualHermiston, 16 August: 10.2 µg/m³, 1.5× usualHermiston, 17 August: 11.2 µg/m³, 1.6× usualHermiston, 18 August: 6.0 µg/m³, 0.9× usualHermiston, 19 August: 77.3 µg/m³, 11× usualHermiston, 20 August: 191.0 µg/m³, 27× usualHermiston, 21 August: 195.0 µg/m³, 28× usualHermiston, 22 August: 20.8 µg/m³, 3.0× usualHermiston, 23 August: 7.5 µg/m³, 1.1× usualHermiston, 24 August: 17.2 µg/m³, 2.5× usualHermiston, 25 August: 17.0 µg/m³, 2.4× usualHermiston, 26 August: 19.9 µg/m³, 2.8× usualHermiston, 27 August: 16.4 µg/m³, 2.3× usualHermiston, 28 August: 17.6 µg/m³, 2.5× usualHermiston, 29 August: 13.1 µg/m³, 1.9× usualHermiston, 30 August: 3.1 µg/m³, 0.4× usualHermiston, 31 August: 5.3 µg/m³, 0.8× usualHermiston, 1 September: 8.9 µg/m³, 1.3× usualHermiston, 2 September: 8.8 µg/m³, 1.3× usualHermiston, 3 September: 6.0 µg/m³, 0.9× usualPendletonPendleton, 14 August: 7.4 µg/m³, 1.0× usualPendleton, 15 August: 8.1 µg/m³, 1.1× usualPendleton, 16 August: 6.5 µg/m³, 0.8× usualPendleton, 17 August: 12.1 µg/m³, 1.6× usualPendleton, 18 August: 6.3 µg/m³, 0.8× usualPendleton, 19 August: 62.3 µg/m³, 8.1× usualPendleton, 20 August: 180.0 µg/m³, 23× usualPendleton, 21 August: 125.0 µg/m³, 16× usualPendleton, 22 August: 25.3 µg/m³, 3.3× usualPendleton, 23 August: 9.1 µg/m³, 1.2× usualPendleton, 24 August: 17.1 µg/m³, 2.2× usualPendleton, 25 August: 14.8 µg/m³, 1.9× usualPendleton, 26 August: 16.9 µg/m³, 2.2× usualPendleton, 27 August: 13.1 µg/m³, 1.7× usualPendleton, 28 August: 11.7 µg/m³, 1.5× usualPendleton, 29 August: 17.6 µg/m³, 2.3× usualPendleton, 30 August: 2.7 µg/m³, 0.4× usualPendleton, 31 August: 3.8 µg/m³, 0.5× usualPendleton, 1 September: 6.7 µg/m³, 0.9× usualPendleton, 2 September: 6.4 µg/m³, 0.8× usualPendleton, 3 September: 4.6 µg/m³, 0.6× usualThe DallesThe Dalles, 14 August: 6.1 µg/m³, 1.1× usualThe Dalles, 15 August: 9.5 µg/m³, 1.6× usualThe Dalles, 16 August: 8.0 µg/m³, 1.4× usualThe Dalles, 17 August: 6.6 µg/m³, 1.1× usualThe Dalles, 18 August: 3.5 µg/m³, 0.6× usualThe Dalles, 19 August: 56.5 µg/m³, 9.7× usualThe Dalles, 20 August: 174.0 µg/m³, 30× usualThe Dalles, 21 August: 99.3 µg/m³, 17× usualThe Dalles, 22 August: 3.1 µg/m³, 0.5× usualThe Dalles, 23 August: 4.9 µg/m³, 0.8× usualThe Dalles, 24 August: 9.7 µg/m³, 1.7× usualThe Dalles, 25 August: 16.1 µg/m³, 2.8× usualThe Dalles, 26 August: 12.8 µg/m³, 2.2× usualThe Dalles, 27 August: 42.3 µg/m³, 7.3× usualThe Dalles, 28 August: 72.3 µg/m³, 12× usualThe Dalles, 29 August: 8.5 µg/m³, 1.5× usualThe Dalles, 30 August: 4.8 µg/m³, 0.8× usualThe Dalles, 31 August: 6.1 µg/m³, 1.1× usualThe Dalles, 1 September: 5.6 µg/m³, 1.0× usualThe Dalles, 2 September: 6.9 µg/m³, 1.2× usualThe Dalles, 3 September: 7.3 µg/m³, 1.3× usualWenatcheeWenatchee, 14 August: 5.2 µg/m³, 0.9× usualWenatchee, 15 August: 8.1 µg/m³, 1.4× usualWenatchee, 16 August: 21.3 µg/m³, 3.6× usualWenatchee, 17 August: 8.2 µg/m³, 1.4× usualWenatchee, 18 August: 4.2 µg/m³, 0.7× usualWenatchee, 19 August: 50.4 µg/m³, 8.5× usualWenatchee, 20 August: 121.0 µg/m³, 21× usualWenatchee, 21 August: 163.0 µg/m³, 28× usualWenatchee, 22 August: 22.9 µg/m³, 3.9× usualWenatchee, 23 August: 4.8 µg/m³, 0.8× usualWenatchee, 24 August: 13.7 µg/m³, 2.3× usualWenatchee, 25 August: 15.0 µg/m³, 2.5× usualWenatchee, 26 August: 13.2 µg/m³, 2.2× usualWenatchee, 27 August: 11.0 µg/m³, 1.9× usualWenatchee, 28 August: 12.3 µg/m³, 2.1× usualWenatchee, 29 August: 20.9 µg/m³, 3.5× usualWenatchee, 30 August: 4.3 µg/m³, 0.7× usualWenatchee, 31 August: 4.1 µg/m³, 0.7× usualWenatchee, 1 September: 5.0 µg/m³, 0.8× usualWenatchee, 2 September: 8.2 µg/m³, 1.4× usualWenatchee, 3 September: 5.9 µg/m³, 1.0× usualSunnysideSunnyside, 14 August: 7.4 µg/m³, 0.9× usualSunnyside, 15 August: 8.0 µg/m³, 1.0× usualSunnyside, 16 August: 19.9 µg/m³, 2.5× usualSunnyside, 17 August: 20.4 µg/m³, 2.6× usualSunnyside, 18 August: 5.8 µg/m³, 0.7× usualSunnyside, 19 August: 85.1 µg/m³, 11× usualSunnyside, 20 August: 148.0 µg/m³, 19× usualSunnyside, 21 August: 158.0 µg/m³, 20× usualSunnyside, 22 August: 53.9 µg/m³, 6.8× usualSunnyside, 23 August: 3.8 µg/m³, 0.5× usualSunnyside, 24 August: 13.1 µg/m³, 1.7× usualSunnyside, 25 August: 17.9 µg/m³, 2.3× usualSunnyside, 26 August: 15.7 µg/m³, 2.0× usualSunnyside, 27 August: 12.9 µg/m³, 1.6× usualSunnyside, 28 August: 16.0 µg/m³, 2.0× usualSunnyside, 29 August: 9.8 µg/m³, 1.2× usualSunnyside, 30 August: 2.9 µg/m³, 0.4× usualSunnyside, 31 August: 3.5 µg/m³, 0.4× usualSunnyside, 1 September: 7.8 µg/m³, 1.0× usualSunnyside, 2 September: 8.8 µg/m³, 1.1× usualSunnyside, 3 September: 5.1 µg/m³, 0.6× usualPascoPasco, 14 August: 4.0 µg/m³, 0.8× usualPasco, 15 August: 4.0 µg/m³, 0.8× usualPasco, 16 August: 8.9 µg/m³, 1.8× usualPasco, 17 August: 7.9 µg/m³, 1.6× usualPasco, 18 August: 1.6 µg/m³, 0.3× usualPasco, 19 August: 93.3 µg/m³, 19× usualPasco, 20 August: 152.0 µg/m³, 30× usualPasco, 21 August: 157.0 µg/m³, 31× usualPasco, 22 August: 19.7 µg/m³, 3.9× usualPasco, 23 August: 3.6 µg/m³, 0.7× usualPasco, 24 August: 7.2 µg/m³, 1.4× usualPasco, 25 August: 9.5 µg/m³, 1.9× usualPasco, 26 August: 11.0 µg/m³, 2.2× usualPasco, 27 August: 9.8 µg/m³, 2.0× usualPasco, 28 August: 9.3 µg/m³, 1.9× usualPasco, 29 August: 5.5 µg/m³, 1.1× usualPasco, 30 August: 0.7 µg/m³, 0.1× usualPasco, 31 August: 2.5 µg/m³, 0.5× usualPasco, 1 September: 3.4 µg/m³, 0.7× usualPasco, 2 September: 5.7 µg/m³, 1.1× usualPasco, 3 September: 2.8 µg/m³, 0.6× usualPullmanPullman, 14 August: 7.3 µg/m³, 0.8× usualPullman, 15 August: 8.0 µg/m³, 0.9× usualPullman, 16 August: 17.3 µg/m³, 2.0× usualPullman, 17 August: 22.0 µg/m³, 2.6× usualPullman, 18 August: 6.1 µg/m³, 0.7× usualPullman, 19 August: 53.5 µg/m³, 6.2× usualPullman, 20 August: 147.0 µg/m³, 17× usualPullman, 21 August: 6.4 µg/m³, 0.7× usualPullman, 22 August: 28.8 µg/m³, 3.3× usualPullman, 23 August: 13.9 µg/m³, 1.6× usualPullman, 24 August: 20.1 µg/m³, 2.3× usualPullman, 25 August: 21.0 µg/m³, 2.4× usualPullman, 26 August: 10.6 µg/m³, 1.2× usualPullman, 27 August: 8.9 µg/m³, 1.0× usualPullman, 28 August: 9.4 µg/m³, 1.1× usualPullman, 29 August: 12.0 µg/m³, 1.4× usualPullman, 30 August: 3.9 µg/m³, 0.5× usualPullman, 31 August: 3.8 µg/m³, 0.4× usualPullman, 1 September: 4.5 µg/m³, 0.5× usualPullman, 2 September: 6.3 µg/m³, 0.7× usualPullman, 3 September: 6.2 µg/m³, 0.7× usualEllensburgEllensburg, 14 August: 5.2 µg/m³, 0.8× usualEllensburg, 15 August: 8.3 µg/m³, 1.3× usualEllensburg, 16 August: 13.0 µg/m³, 2.1× usualEllensburg, 17 August: 8.0 µg/m³, 1.3× usualEllensburg, 18 August: 5.7 µg/m³, 0.9× usualEllensburg, 19 August: 67.2 µg/m³, 11× usualEllensburg, 20 August: 145.0 µg/m³, 23× usualEllensburg, 21 August: 139.0 µg/m³, 22× usualEllensburg, 22 August: 10.0 µg/m³, 1.6× usualEllensburg, 23 August: 3.3 µg/m³, 0.5× usualEllensburg, 24 August: 14.7 µg/m³, 2.4× usualEllensburg, 25 August: 17.4 µg/m³, 2.8× usualEllensburg, 26 August: 12.4 µg/m³, 2.0× usualEllensburg, 27 August: 9.2 µg/m³, 1.5× usualEllensburg, 28 August: 13.4 µg/m³, 2.2× usualEllensburg, 29 August: 8.6 µg/m³, 1.4× usualEllensburg, 30 August: 6.1 µg/m³, 1.0× usualEllensburg, 31 August: 3.8 µg/m³, 0.6× usualEllensburg, 1 September: 5.3 µg/m³, 0.9× usualEllensburg, 2 September: 6.3 µg/m³, 1.0× usualEllensburg, 3 September: 6.2 µg/m³, 1.0× usualCoeur d'AleneCoeur d'Alene, 14 August: 13.0 µg/m³, 1.3× usualCoeur d'Alene, 15 August: 10.8 µg/m³, 1.1× usualCoeur d'Alene, 16 August: 14.8 µg/m³, 1.5× usualCoeur d'Alene, 17 August: 24.5 µg/m³, 2.5× usualCoeur d'Alene, 18 August: 24.5 µg/m³, 2.5× usualCoeur d'Alene, 19 August: 142.0 µg/m³, 14× usualCoeur d'Alene, 20 August: 102.0 µg/m³, 10× usualCoeur d'Alene, 21 August: 41.0 µg/m³, 4.2× usualCoeur d'Alene, 22 August: 27.4 µg/m³, 2.8× usualCoeur d'Alene, 23 August: 16.3 µg/m³, 1.7× usualCoeur d'Alene, 24 August: 10.8 µg/m³, 1.1× usualCoeur d'Alene, 25 August: 13.8 µg/m³, 1.4× usualCoeur d'Alene, 26 August: 15.5 µg/m³, 1.6× usualCoeur d'Alene, 27 August: 15.4 µg/m³, 1.6× usualCoeur d'Alene, 28 August: 12.8 µg/m³, 1.3× usualCoeur d'Alene, 29 August: 15.8 µg/m³, 1.6× usualCoeur d'Alene, 30 August: 4.3 µg/m³, 0.4× usualCoeur d'Alene, 31 August: 3.3 µg/m³, 0.3× usualCoeur d'Alene, 1 September: 4.1 µg/m³, 0.4× usualCoeur d'Alene, 2 September: 3.8 µg/m³, 0.4× usualCoeur d'Alene, 3 September: 4.3 µg/m³, 0.4× usualYakimaYakima, 14 August: 5.3 µg/m³, 0.8× usualYakima, 15 August: 9.7 µg/m³, 1.4× usualYakima, 16 August: 14.6 µg/m³, 2.1× usualYakima, 17 August: 7.3 µg/m³, 1.0× usualYakima, 18 August: 5.1 µg/m³, 0.7× usualYakima, 19 August: 77.5 µg/m³, 11× usualYakima, 20 August: 140.0 µg/m³, 20× usualYakima, 21 August: 141.0 µg/m³, 20× usualYakima, 22 August: 20.9 µg/m³, 3.0× usualYakima, 23 August: 3.5 µg/m³, 0.5× usualYakima, 24 August: 13.7 µg/m³, 2.0× usualYakima, 25 August: 14.8 µg/m³, 2.1× usualYakima, 26 August: 14.3 µg/m³, 2.0× usualYakima, 27 August: 12.0 µg/m³, 1.7× usualYakima, 28 August: 12.8 µg/m³, 1.8× usualYakima, 29 August: 8.8 µg/m³, 1.3× usualYakima, 30 August: 3.0 µg/m³, 0.4× usualYakima, 31 August: 4.8 µg/m³, 0.7× usualYakima, 1 September: 6.7 µg/m³, 1.0× usualYakima, 2 September: 8.4 µg/m³, 1.2× usualYakima, 3 September: 7.8 µg/m³, 1.1× usualChilliwackChilliwack, 14 August: 8.6 µg/m³, 1.3× usualChilliwack, 15 August: 8.7 µg/m³, 1.4× usualChilliwack, 16 August: 5.4 µg/m³, 0.8× usualChilliwack, 17 August: 7.3 µg/m³, 1.1× usualChilliwack, 18 August: 2.8 µg/m³, 0.4× usualChilliwack, 19 August: 29.6 µg/m³, 4.6× usualChilliwack, 20 August: 115.0 µg/m³, 18× usualChilliwack, 21 August: 24.6 µg/m³, 3.8× usualChilliwack, 22 August: 4.4 µg/m³, 0.7× usualChilliwack, 23 August: 5.1 µg/m³, 0.8× usualChilliwack, 24 August: 21.1 µg/m³, 3.3× usualChilliwack, 25 August: 49.7 µg/m³, 7.8× usualChilliwack, 26 August: 38.3 µg/m³, 6.0× usualChilliwack, 27 August: 48.0 µg/m³, 7.5× usualChilliwack, 28 August: 25.3 µg/m³, 4.0× usualChilliwack, 29 August: no readingChilliwack, 30 August: no readingChilliwack, 31 August: 6.9 µg/m³, 1.1× usualChilliwack, 1 September: 8.6 µg/m³, 1.3× usualChilliwack, 2 September: 12.9 µg/m³, 2.0× usualChilliwack, 3 September: 8.9 µg/m³, 1.4× usualAuburnAuburn, 14 August: 11.0 µg/m³, 1.9× usualAuburn, 15 August: 9.9 µg/m³, 1.7× usualAuburn, 16 August: 8.5 µg/m³, 1.4× usualAuburn, 17 August: 8.2 µg/m³, 1.4× usualAuburn, 18 August: 7.8 µg/m³, 1.3× usualAuburn, 19 August: 11.0 µg/m³, 1.9× usualAuburn, 20 August: 70.5 µg/m³, 12× usualAuburn, 21 August: 55.8 µg/m³, 9.5× usualAuburn, 22 August: 4.4 µg/m³, 0.7× usualAuburn, 23 August: 5.5 µg/m³, 0.9× usualAuburn, 24 August: 9.4 µg/m³, 1.6× usualAuburn, 25 August: 16.7 µg/m³, 2.8× usualAuburn, 26 August: 27.9 µg/m³, 4.7× usualAuburn, 27 August: 24.2 µg/m³, 4.1× usualAuburn, 28 August: 13.4 µg/m³, 2.3× usualAuburn, 29 August: 7.7 µg/m³, 1.3× usualAuburn, 30 August: 4.2 µg/m³, 0.7× usualAuburn, 31 August: 7.4 µg/m³, 1.3× usualAuburn, 1 September: 8.9 µg/m³, 1.5× usualAuburn, 2 September: 9.3 µg/m³, 1.6× usualAuburn, 3 September: 7.1 µg/m³, 1.2× usualSquamishSquamish, 14 August: 6.4 µg/m³, 0.9× usualSquamish, 15 August: 9.3 µg/m³, 1.3× usualSquamish, 16 August: no readingSquamish, 17 August: 8.4 µg/m³, 1.2× usualSquamish, 18 August: 9.1 µg/m³, 1.2× usualSquamish, 19 August: 14.5 µg/m³, 2.0× usualSquamish, 20 August: 69.2 µg/m³, 9.5× usualSquamish, 21 August: 42.8 µg/m³, 5.9× usualSquamish, 22 August: 12.6 µg/m³, 1.7× usualSquamish, 23 August: 3.8 µg/m³, 0.5× usualSquamish, 24 August: 12.3 µg/m³, 1.7× usualSquamish, 25 August: 38.7 µg/m³, 5.3× usualSquamish, 26 August: 36.3 µg/m³, 5.0× usualSquamish, 27 August: 23.3 µg/m³, 3.2× usualSquamish, 28 August: 21.6 µg/m³, 3.0× usualSquamish, 29 August: 11.7 µg/m³, 1.6× usualSquamish, 30 August: 7.2 µg/m³, 1.0× usualSquamish, 31 August: 7.4 µg/m³, 1.0× usualSquamish, 1 September: 8.6 µg/m³, 1.2× usualSquamish, 2 September: 14.1 µg/m³, 1.9× usualSquamish, 3 September: 11.0 µg/m³, 1.5× usualCoquitlamCoquitlam, 14 August: 8.1 µg/m³, 1.5× usualCoquitlam, 15 August: 8.3 µg/m³, 1.6× usualCoquitlam, 16 August: 5.9 µg/m³, 1.1× usualCoquitlam, 17 August: 5.6 µg/m³, 1.1× usualCoquitlam, 18 August: 2.7 µg/m³, 0.5× usualCoquitlam, 19 August: 11.3 µg/m³, 2.1× usualCoquitlam, 20 August: 62.5 µg/m³, 12× usualCoquitlam, 21 August: 16.4 µg/m³, 3.1× usualCoquitlam, 22 August: 2.3 µg/m³, 0.4× usualCoquitlam, 23 August: 3.7 µg/m³, 0.7× usualCoquitlam, 24 August: 8.9 µg/m³, 1.7× usualCoquitlam, 25 August: 35.9 µg/m³, 6.8× usualCoquitlam, 26 August: 29.5 µg/m³, 5.6× usualCoquitlam, 27 August: 22.2 µg/m³, 4.2× usualCoquitlam, 28 August: 18.8 µg/m³, 3.5× usualCoquitlam, 29 August: 12.7 µg/m³, 2.4× usualCoquitlam, 30 August: 5.8 µg/m³, 1.1× usualCoquitlam, 31 August: 5.4 µg/m³, 1.0× usualCoquitlam, 1 September: 6.9 µg/m³, 1.3× usualCoquitlam, 2 September: 10.8 µg/m³, 2.0× usualCoquitlam, 3 September: 9.6 µg/m³, 1.8× usualIssaquahIssaquah, 14 August: 5.0 µg/m³, 1.0× usualIssaquah, 15 August: 4.7 µg/m³, 0.9× usualIssaquah, 16 August: 4.3 µg/m³, 0.9× usualIssaquah, 17 August: 4.2 µg/m³, 0.8× usualIssaquah, 18 August: 4.5 µg/m³, 0.9× usualIssaquah, 19 August: 9.6 µg/m³, 1.9× usualIssaquah, 20 August: 60.7 µg/m³, 12× usualIssaquah, 21 August: 57.8 µg/m³, 12× usualIssaquah, 22 August: 1.8 µg/m³, 0.4× usualIssaquah, 23 August: 3.8 µg/m³, 0.8× usualIssaquah, 24 August: 11.2 µg/m³, 2.2× usualIssaquah, 25 August: 18.7 µg/m³, 3.7× usualIssaquah, 26 August: 30.1 µg/m³, 6.0× usualIssaquah, 27 August: 34.9 µg/m³, 7.0× usualIssaquah, 28 August: 19.9 µg/m³, 4.0× usualIssaquah, 29 August: 8.7 µg/m³, 1.7× usualIssaquah, 30 August: 4.6 µg/m³, 0.9× usualIssaquah, 31 August: 6.5 µg/m³, 1.3× usualIssaquah, 1 September: 9.3 µg/m³, 1.9× usualIssaquah, 2 September: 8.4 µg/m³, 1.7× usualIssaquah, 3 September: 6.7 µg/m³, 1.3× usualColumbia CityColumbia City, 14 August: 9.2 µg/m³, 1.3× usualColumbia City, 15 August: 9.9 µg/m³, 1.4× usualColumbia City, 16 August: 10.3 µg/m³, 1.5× usualColumbia City, 17 August: 9.2 µg/m³, 1.3× usualColumbia City, 18 August: 8.4 µg/m³, 1.2× usualColumbia City, 19 August: 12.4 µg/m³, 1.8× usualColumbia City, 20 August: 60.3 µg/m³, 8.7× usualColumbia City, 21 August: 30.3 µg/m³, 4.4× usualColumbia City, 22 August: 5.1 µg/m³, 0.7× usualColumbia City, 23 August: 6.1 µg/m³, 0.9× usualColumbia City, 24 August: 10.0 µg/m³, 1.4× usualColumbia City, 25 August: 18.9 µg/m³, 2.7× usualColumbia City, 26 August: 33.7 µg/m³, 4.9× usualColumbia City, 27 August: 24.6 µg/m³, 3.6× usualColumbia City, 28 August: 15.1 µg/m³, 2.2× usualColumbia City, 29 August: 8.9 µg/m³, 1.3× usualColumbia City, 30 August: 5.5 µg/m³, 0.8× usualColumbia City, 31 August: 8.7 µg/m³, 1.3× usualColumbia City, 1 September: 8.3 µg/m³, 1.2× usualColumbia City, 2 September: 11.8 µg/m³, 1.7× usualColumbia City, 3 September: 6.7 µg/m³, 1.0× usualShorelineShoreline, 14 August: 5.8 µg/m³, 1.1× usualShoreline, 15 August: 6.3 µg/m³, 1.2× usualShoreline, 16 August: 5.7 µg/m³, 1.1× usualShoreline, 17 August: 6.5 µg/m³, 1.3× usualShoreline, 18 August: 7.6 µg/m³, 1.5× usualShoreline, 19 August: 9.7 µg/m³, 1.9× usualShoreline, 20 August: 59.3 µg/m³, 11× usualShoreline, 21 August: 23.8 µg/m³, 4.6× usualShoreline, 22 August: 3.4 µg/m³, 0.7× usualShoreline, 23 August: 5.4 µg/m³, 1.0× usualShoreline, 24 August: 9.0 µg/m³, 1.7× usualShoreline, 25 August: 17.7 µg/m³, 3.4× usualShoreline, 26 August: 32.0 µg/m³, 6.2× usualShoreline, 27 August: 27.3 µg/m³, 5.3× usualShoreline, 28 August: 17.1 µg/m³, 3.3× usualShoreline, 29 August: 8.9 µg/m³, 1.7× usualShoreline, 30 August: 5.6 µg/m³, 1.1× usualShoreline, 31 August: 6.8 µg/m³, 1.3× usualShoreline, 1 September: 7.8 µg/m³, 1.5× usualShoreline, 2 September: 10.8 µg/m³, 2.1× usualShoreline, 3 September: 7.8 µg/m³, 1.5× usualParklandParkland, 14 August: 7.5 µg/m³, 1.5× usualParkland, 15 August: 6.5 µg/m³, 1.3× usualParkland, 16 August: 8.5 µg/m³, 1.7× usualParkland, 17 August: 7.5 µg/m³, 1.5× usualParkland, 18 August: 9.5 µg/m³, 1.9× usualParkland, 19 August: 11.0 µg/m³, 2.2× usualParkland, 20 August: 56.2 µg/m³, 11× usualParkland, 21 August: 22.0 µg/m³, 4.4× usualParkland, 22 August: 3.3 µg/m³, 0.7× usualParkland, 23 August: 3.3 µg/m³, 0.7× usualParkland, 24 August: 10.6 µg/m³, 2.1× usualParkland, 25 August: 16.3 µg/m³, 3.3× usualParkland, 26 August: 29.2 µg/m³, 5.8× usualParkland, 27 August: 17.5 µg/m³, 3.5× usualParkland, 28 August: 12.7 µg/m³, 2.5× usualParkland, 29 August: 7.0 µg/m³, 1.4× usualParkland, 30 August: 2.8 µg/m³, 0.6× usualParkland, 31 August: 7.1 µg/m³, 1.4× usualParkland, 1 September: 9.4 µg/m³, 1.9× usualParkland, 2 September: 11.4 µg/m³, 2.3× usualParkland, 3 September: 6.5 µg/m³, 1.3× usualTacomaTacoma, 14 August: 8.0 µg/m³, 1.5× usualTacoma, 15 August: 8.3 µg/m³, 1.5× usualTacoma, 16 August: 8.7 µg/m³, 1.6× usualTacoma, 17 August: 8.2 µg/m³, 1.5× usualTacoma, 18 August: 9.6 µg/m³, 1.8× usualTacoma, 19 August: 10.9 µg/m³, 2.0× usualTacoma, 20 August: 52.6 µg/m³, 9.7× usualTacoma, 21 August: 23.4 µg/m³, 4.3× usualTacoma, 22 August: 3.7 µg/m³, 0.7× usualTacoma, 23 August: 4.4 µg/m³, 0.8× usualTacoma, 24 August: 10.5 µg/m³, 1.9× usualTacoma, 25 August: 17.7 µg/m³, 3.3× usualTacoma, 26 August: 31.9 µg/m³, 5.9× usualTacoma, 27 August: 18.1 µg/m³, 3.4× usualTacoma, 28 August: 13.3 µg/m³, 2.5× usualTacoma, 29 August: 7.2 µg/m³, 1.3× usualTacoma, 30 August: 4.5 µg/m³, 0.8× usualTacoma, 31 August: 7.3 µg/m³, 1.4× usualTacoma, 1 September: 7.8 µg/m³, 1.4× usualTacoma, 2 September: 12.7 µg/m³, 2.4× usualTacoma, 3 September: 6.2 µg/m³, 1.1× usualRentonRenton, 14 August: 9.2 µg/m³, 1.5× usualRenton, 15 August: 8.9 µg/m³, 1.5× usualRenton, 16 August: 11.3 µg/m³, 1.9× usualRenton, 17 August: 8.9 µg/m³, 1.5× usualRenton, 18 August: 9.5 µg/m³, 1.6× usualRenton, 19 August: 11.1 µg/m³, 1.8× usualRenton, 20 August: 52.3 µg/m³, 8.7× usualRenton, 21 August: 27.8 µg/m³, 4.6× usualRenton, 22 August: 5.0 µg/m³, 0.8× usualRenton, 23 August: 5.5 µg/m³, 0.9× usualRenton, 24 August: 10.4 µg/m³, 1.7× usualRenton, 25 August: 19.5 µg/m³, 3.3× usualRenton, 26 August: 33.5 µg/m³, 5.6× usualRenton, 27 August: 25.1 µg/m³, 4.2× usualRenton, 28 August: 15.7 µg/m³, 2.6× usualRenton, 29 August: 9.3 µg/m³, 1.6× usualRenton, 30 August: 5.3 µg/m³, 0.9× usualRenton, 31 August: 9.1 µg/m³, 1.5× usualRenton, 1 September: 9.2 µg/m³, 1.5× usualRenton, 2 September: 12.6 µg/m³, 2.1× usualRenton, 3 September: 7.8 µg/m³, 1.3× usualOrchardsOrchards, 14 August: 7.1 µg/m³, 1.4× usualOrchards, 15 August: 7.7 µg/m³, 1.5× usualOrchards, 16 August: 3.4 µg/m³, 0.7× usualOrchards, 17 August: 4.1 µg/m³, 0.8× usualOrchards, 18 August: 3.1 µg/m³, 0.6× usualOrchards, 19 August: 10.0 µg/m³, 2.0× usualOrchards, 20 August: 48.4 µg/m³, 9.7× usualOrchards, 21 August: 7.6 µg/m³, 1.5× usualOrchards, 22 August: 2.0 µg/m³, 0.4× usualOrchards, 23 August: 3.4 µg/m³, 0.7× usualOrchards, 24 August: 7.0 µg/m³, 1.4× usualOrchards, 25 August: 13.8 µg/m³, 2.8× usualOrchards, 26 August: 12.6 µg/m³, 2.5× usualOrchards, 27 August: 15.7 µg/m³, 3.1× usualOrchards, 28 August: 8.5 µg/m³, 1.7× usualOrchards, 29 August: 6.0 µg/m³, 1.2× usualOrchards, 30 August: 1.5 µg/m³, 0.3× usualOrchards, 31 August: 28.7 µg/m³, 5.7× usualOrchards, 1 September: 4.3 µg/m³, 0.9× usualOrchards, 2 September: 4.0 µg/m³, 0.8× usualOrchards, 3 September: 4.4 µg/m³, 0.9× usualSeattleSeattle, 14 August: 8.4 µg/m³, 1.4× usualSeattle, 15 August: 9.3 µg/m³, 1.5× usualSeattle, 16 August: 9.1 µg/m³, 1.5× usualSeattle, 17 August: 9.5 µg/m³, 1.5× usualSeattle, 18 August: 9.5 µg/m³, 1.5× usualSeattle, 19 August: 11.7 µg/m³, 1.9× usualSeattle, 20 August: 45.7 µg/m³, 7.4× usualSeattle, 21 August: 23.7 µg/m³, 3.8× usualSeattle, 22 August: 4.7 µg/m³, 0.8× usualSeattle, 23 August: 6.1 µg/m³, 1.0× usualSeattle, 24 August: 11.0 µg/m³, 1.8× usualSeattle, 25 August: 20.3 µg/m³, 3.3× usualSeattle, 26 August: 34.0 µg/m³, 5.5× usualSeattle, 27 August: 26.8 µg/m³, 4.3× usualSeattle, 28 August: 16.1 µg/m³, 2.6× usualSeattle, 29 August: 9.4 µg/m³, 1.5× usualSeattle, 30 August: 6.0 µg/m³, 1.0× usualSeattle, 31 August: 7.8 µg/m³, 1.3× usualSeattle, 1 September: 8.8 µg/m³, 1.4× usualSeattle, 2 September: 13.9 µg/m³, 2.2× usualSeattle, 3 September: 9.0 µg/m³, 1.5× usualWest VancouverWest Vancouver, 14 August: 7.0 µg/m³, 1.3× usualWest Vancouver, 15 August: 7.0 µg/m³, 1.3× usualWest Vancouver, 16 August: 4.8 µg/m³, 0.9× usualWest Vancouver, 17 August: 3.7 µg/m³, 0.7× usualWest Vancouver, 18 August: 2.9 µg/m³, 0.6× usualWest Vancouver, 19 August: 11.1 µg/m³, 2.1× usualWest Vancouver, 20 August: 45.0 µg/m³, 8.7× usualWest Vancouver, 21 August: 21.0 µg/m³, 4.0× usualWest Vancouver, 22 August: 3.4 µg/m³, 0.7× usualWest Vancouver, 23 August: 3.7 µg/m³, 0.7× usualWest Vancouver, 24 August: 10.8 µg/m³, 2.1× usualWest Vancouver, 25 August: 28.4 µg/m³, 5.5× usualWest Vancouver, 26 August: 33.5 µg/m³, 6.4× usualWest Vancouver, 27 August: 23.8 µg/m³, 4.6× usualWest Vancouver, 28 August: 20.9 µg/m³, 4.0× usualWest Vancouver, 29 August: 9.8 µg/m³, 1.9× usualWest Vancouver, 30 August: 5.9 µg/m³, 1.1× usualWest Vancouver, 31 August: 6.7 µg/m³, 1.3× usualWest Vancouver, 1 September: 5.8 µg/m³, 1.1× usualWest Vancouver, 2 September: 11.5 µg/m³, 2.2× usualWest Vancouver, 3 September: 7.8 µg/m³, 1.5× usualCanbyCanby, 14 August: 11.1 µg/m³, 2.2× usualCanby, 15 August: 15.6 µg/m³, 3.1× usualCanby, 16 August: 8.5 µg/m³, 1.7× usualCanby, 17 August: 7.2 µg/m³, 1.4× usualCanby, 18 August: 4.6 µg/m³, 0.9× usualCanby, 19 August: 13.8 µg/m³, 2.8× usualCanby, 20 August: 44.7 µg/m³, 8.9× usualCanby, 21 August: 14.5 µg/m³, 2.9× usualCanby, 22 August: 3.5 µg/m³, 0.7× usualCanby, 23 August: 5.2 µg/m³, 1.0× usualCanby, 24 August: 8.9 µg/m³, 1.8× usualCanby, 25 August: 18.2 µg/m³, 3.6× usualCanby, 26 August: 21.3 µg/m³, 4.3× usualCanby, 27 August: 18.2 µg/m³, 3.6× usualCanby, 28 August: 12.9 µg/m³, 2.6× usualCanby, 29 August: 10.8 µg/m³, 2.2× usualCanby, 30 August: 3.1 µg/m³, 0.6× usualCanby, 31 August: 5.2 µg/m³, 1.0× usualCanby, 1 September: 8.5 µg/m³, 1.7× usualCanby, 2 September: 10.9 µg/m³, 2.2× usualCanby, 3 September: 6.5 µg/m³, 1.3× usualGreshamGresham, 14 August: 9.3 µg/m³, 1.9× usualGresham, 15 August: 15.7 µg/m³, 3.1× usualGresham, 16 August: 5.5 µg/m³, 1.1× usualGresham, 17 August: 4.6 µg/m³, 0.9× usualGresham, 18 August: 3.1 µg/m³, 0.6× usualGresham, 19 August: 9.6 µg/m³, 1.9× usualGresham, 20 August: 41.5 µg/m³, 8.3× usualGresham, 21 August: 9.9 µg/m³, 2.0× usualGresham, 22 August: 3.2 µg/m³, 0.6× usualGresham, 23 August: 5.2 µg/m³, 1.0× usualGresham, 24 August: 10.1 µg/m³, 2.0× usualGresham, 25 August: 16.7 µg/m³, 3.3× usualGresham, 26 August: 15.7 µg/m³, 3.1× usualGresham, 27 August: 17.0 µg/m³, 3.4× usualGresham, 28 August: 10.6 µg/m³, 2.1× usualGresham, 29 August: 8.7 µg/m³, 1.7× usualGresham, 30 August: 2.3 µg/m³, 0.5× usualGresham, 31 August: 8.8 µg/m³, 1.8× usualGresham, 1 September: 5.8 µg/m³, 1.2× usualGresham, 2 September: 6.8 µg/m³, 1.4× usualGresham, 3 September: 5.8 µg/m³, 1.2× usualBremertonBremerton, 14 August: 3.3 µg/m³, 0.7× usualBremerton, 15 August: 3.0 µg/m³, 0.6× usualBremerton, 16 August: 4.3 µg/m³, 0.9× usualBremerton, 17 August: 5.1 µg/m³, 1.0× usualBremerton, 18 August: 8.3 µg/m³, 1.7× usualBremerton, 19 August: 12.8 µg/m³, 2.6× usualBremerton, 20 August: 41.0 µg/m³, 8.2× usualBremerton, 21 August: 22.4 µg/m³, 4.5× usualBremerton, 22 August: 2.7 µg/m³, 0.5× usualBremerton, 23 August: 4.3 µg/m³, 0.9× usualBremerton, 24 August: 9.3 µg/m³, 1.9× usualBremerton, 25 August: 18.4 µg/m³, 3.7× usualBremerton, 26 August: 30.2 µg/m³, 6.0× usualBremerton, 27 August: 19.3 µg/m³, 3.9× usualBremerton, 28 August: 16.0 µg/m³, 3.2× usualBremerton, 29 August: 8.8 µg/m³, 1.8× usualBremerton, 30 August: 5.0 µg/m³, 1.0× usualBremerton, 31 August: 5.0 µg/m³, 1.0× usualBremerton, 1 September: 5.7 µg/m³, 1.1× usualBremerton, 2 September: 11.3 µg/m³, 2.3× usualBremerton, 3 September: 7.3 µg/m³, 1.5× usualTigardTigard, 14 August: 13.2 µg/m³, 2.3× usualTigard, 15 August: 19.5 µg/m³, 3.4× usualTigard, 16 August: 12.1 µg/m³, 2.1× usualTigard, 17 August: 8.5 µg/m³, 1.5× usualTigard, 18 August: 5.4 µg/m³, 0.9× usualTigard, 19 August: 15.2 µg/m³, 2.6× usualTigard, 20 August: 40.3 µg/m³, 6.9× usualTigard, 21 August: 15.6 µg/m³, 2.7× usualTigard, 22 August: 4.6 µg/m³, 0.8× usualTigard, 23 August: 6.8 µg/m³, 1.2× usualTigard, 24 August: 12.4 µg/m³, 2.1× usualTigard, 25 August: 21.3 µg/m³, 3.7× usualTigard, 26 August: 22.8 µg/m³, 3.9× usualTigard, 27 August: 20.1 µg/m³, 3.5× usualTigard, 28 August: 15.5 µg/m³, 2.7× usualTigard, 29 August: 11.3 µg/m³, 1.9× usualTigard, 30 August: 4.3 µg/m³, 0.7× usualTigard, 31 August: 6.6 µg/m³, 1.1× usualTigard, 1 September: 8.4 µg/m³, 1.4× usualTigard, 2 September: 11.5 µg/m³, 2.0× usualTigard, 3 September: no readingHillsboroHillsboro, 14 August: 10.9 µg/m³, 2.2× usualHillsboro, 15 August: 13.3 µg/m³, 2.7× usualHillsboro, 16 August: 7.6 µg/m³, 1.5× usualHillsboro, 17 August: 7.3 µg/m³, 1.5× usualHillsboro, 18 August: 4.2 µg/m³, 0.8× usualHillsboro, 19 August: 12.1 µg/m³, 2.4× usualHillsboro, 20 August: 40.0 µg/m³, 8.0× usualHillsboro, 21 August: 6.8 µg/m³, 1.4× usualHillsboro, 22 August: 4.2 µg/m³, 0.8× usualHillsboro, 23 August: 6.6 µg/m³, 1.3× usualHillsboro, 24 August: 10.3 µg/m³, 2.1× usualHillsboro, 25 August: 19.6 µg/m³, 3.9× usualHillsboro, 26 August: 18.2 µg/m³, 3.6× usualHillsboro, 27 August: 17.9 µg/m³, 3.6× usualHillsboro, 28 August: 10.5 µg/m³, 2.1× usualHillsboro, 29 August: no readingHillsboro, 30 August: 2.9 µg/m³, 0.6× usualHillsboro, 31 August: 3.2 µg/m³, 0.6× usualHillsboro, 1 September: 3.5 µg/m³, 0.7× usualHillsboro, 2 September: 6.2 µg/m³, 1.2× usualHillsboro, 3 September: 5.0 µg/m³, 1.0× usualBurnabyBurnaby, 14 August: 6.3 µg/m³, 1.2× usualBurnaby, 15 August: 7.2 µg/m³, 1.3× usualBurnaby, 16 August: 5.3 µg/m³, 1.0× usualBurnaby, 17 August: 4.8 µg/m³, 0.9× usualBurnaby, 18 August: 2.3 µg/m³, 0.4× usualBurnaby, 19 August: 20.3 µg/m³, 3.8× usualBurnaby, 20 August: 39.7 µg/m³, 7.4× usualBurnaby, 21 August: 17.2 µg/m³, 3.2× usualBurnaby, 22 August: 2.2 µg/m³, 0.4× usualBurnaby, 23 August: 6.2 µg/m³, 1.1× usualBurnaby, 24 August: 11.4 µg/m³, 2.1× usualBurnaby, 25 August: 37.0 µg/m³, 6.9× usualBurnaby, 26 August: 26.9 µg/m³, 5.0× usualBurnaby, 27 August: 21.7 µg/m³, 4.0× usualBurnaby, 28 August: 19.1 µg/m³, 3.5× usualBurnaby, 29 August: 11.5 µg/m³, 2.1× usualBurnaby, 30 August: 4.5 µg/m³, 0.8× usualBurnaby, 31 August: 6.1 µg/m³, 1.1× usualBurnaby, 1 September: 4.0 µg/m³, 0.7× usualBurnaby, 2 September: 10.2 µg/m³, 1.9× usualBurnaby, 3 September: 8.5 µg/m³, 1.6× usualAbbotsfordAbbotsford, 14 August: 7.1 µg/m³, 1.2× usualAbbotsford, 15 August: 7.6 µg/m³, 1.3× usualAbbotsford, 16 August: 5.8 µg/m³, 1.0× usualAbbotsford, 17 August: 4.8 µg/m³, 0.8× usualAbbotsford, 18 August: 2.8 µg/m³, 0.5× usualAbbotsford, 19 August: 21.9 µg/m³, 3.8× usualAbbotsford, 20 August: 39.7 µg/m³, 7.0× usualAbbotsford, 21 August: 12.2 µg/m³, 2.1× usualAbbotsford, 22 August: 2.0 µg/m³, 0.4× usualAbbotsford, 23 August: 7.9 µg/m³, 1.4× usualAbbotsford, 24 August: 13.7 µg/m³, 2.4× usualAbbotsford, 25 August: 36.8 µg/m³, 6.5× usualAbbotsford, 26 August: 37.3 µg/m³, 6.5× usualAbbotsford, 27 August: 29.8 µg/m³, 5.2× usualAbbotsford, 28 August: 17.0 µg/m³, 3.0× usualAbbotsford, 29 August: 9.7 µg/m³, 1.7× usualAbbotsford, 30 August: 4.8 µg/m³, 0.8× usualAbbotsford, 31 August: 4.5 µg/m³, 0.8× usualAbbotsford, 1 September: 6.4 µg/m³, 1.1× usualAbbotsford, 2 September: 13.4 µg/m³, 2.4× usualAbbotsford, 3 September: 8.9 µg/m³, 1.6× usualBellevueBellevue, 14 August: 5.9 µg/m³, 1.2× usualBellevue, 15 August: 5.2 µg/m³, 1.0× usualBellevue, 16 August: 5.2 µg/m³, 1.0× usualBellevue, 17 August: 4.9 µg/m³, 1.0× usualBellevue, 18 August: 5.4 µg/m³, 1.1× usualBellevue, 19 August: 8.4 µg/m³, 1.7× usualBellevue, 20 August: 39.6 µg/m³, 7.9× usualBellevue, 21 August: 23.5 µg/m³, 4.7× usualBellevue, 22 August: 3.2 µg/m³, 0.6× usualBellevue, 23 August: 4.2 µg/m³, 0.8× usualBellevue, 24 August: 8.3 µg/m³, 1.7× usualBellevue, 25 August: 13.9 µg/m³, 2.8× usualBellevue, 26 August: 24.0 µg/m³, 4.8× usualBellevue, 27 August: 23.1 µg/m³, 4.6× usualBellevue, 28 August: 13.4 µg/m³, 2.7× usualBellevue, 29 August: 6.7 µg/m³, 1.3× usualBellevue, 30 August: 4.6 µg/m³, 0.9× usualBellevue, 31 August: 5.9 µg/m³, 1.2× usualBellevue, 1 September: 7.4 µg/m³, 1.5× usualBellevue, 2 September: 8.2 µg/m³, 1.6× usualBellevue, 3 September: 5.3 µg/m³, 1.1× usualSalmon CreekSalmon Creek, 14 August: 10.3 µg/m³, 2.1× usualSalmon Creek, 15 August: 11.2 µg/m³, 2.2× usualSalmon Creek, 16 August: 8.5 µg/m³, 1.7× usualSalmon Creek, 17 August: 8.0 µg/m³, 1.6× usualSalmon Creek, 18 August: 5.8 µg/m³, 1.2× usualSalmon Creek, 19 August: 12.5 µg/m³, 2.5× usualSalmon Creek, 20 August: 39.4 µg/m³, 7.9× usualSalmon Creek, 21 August: 7.3 µg/m³, 1.5× usualSalmon Creek, 22 August: 4.2 µg/m³, 0.8× usualSalmon Creek, 23 August: 5.6 µg/m³, 1.1× usualSalmon Creek, 24 August: 11.2 µg/m³, 2.2× usualSalmon Creek, 25 August: 22.0 µg/m³, 4.4× usualSalmon Creek, 26 August: 20.0 µg/m³, 4.0× usualSalmon Creek, 27 August: 20.4 µg/m³, 4.1× usualSalmon Creek, 28 August: 13.8 µg/m³, 2.8× usualSalmon Creek, 29 August: 8.7 µg/m³, 1.7× usualSalmon Creek, 30 August: 4.0 µg/m³, 0.8× usualSalmon Creek, 31 August: 8.9 µg/m³, 1.8× usualSalmon Creek, 1 September: 8.1 µg/m³, 1.6× usualSalmon Creek, 2 September: 9.5 µg/m³, 1.9× usualSalmon Creek, 3 September: 10.0 µg/m³, 2.0× usualRoseburgRoseburg, 14 August: 20.8 µg/m³, 4.2× usualRoseburg, 15 August: 20.9 µg/m³, 4.2× usualRoseburg, 16 August: 15.4 µg/m³, 3.1× usualRoseburg, 17 August: 11.5 µg/m³, 2.3× usualRoseburg, 18 August: 3.8 µg/m³, 0.8× usualRoseburg, 19 August: 8.9 µg/m³, 1.8× usualRoseburg, 20 August: 16.7 µg/m³, 3.3× usualRoseburg, 21 August: 25.4 µg/m³, 5.1× usualRoseburg, 22 August: 3.4 µg/m³, 0.7× usualRoseburg, 23 August: 4.7 µg/m³, 0.9× usualRoseburg, 24 August: 18.6 µg/m³, 3.7× usualRoseburg, 25 August: 75.6 µg/m³, 15× usualRoseburg, 26 August: 103.0 µg/m³, 21× usualRoseburg, 27 August: 202.0 µg/m³, 40× usualRoseburg, 28 August: 184.0 µg/m³, 37× usualRoseburg, 29 August: 43.3 µg/m³, 8.7× usualRoseburg, 30 August: 40.0 µg/m³, 8.0× usualRoseburg, 31 August: 78.4 µg/m³, 16× usualRoseburg, 1 September: 30.8 µg/m³, 6.2× usualRoseburg, 2 September: 12.3 µg/m³, 2.5× usualRoseburg, 3 September: 13.8 µg/m³, 2.8× usualReddingRedding, 14 August: 8.9 µg/m³, 1.5× usualRedding, 15 August: 7.5 µg/m³, 1.2× usualRedding, 16 August: 8.9 µg/m³, 1.5× usualRedding, 17 August: 15.1 µg/m³, 2.5× usualRedding, 18 August: 24.0 µg/m³, 3.9× usualRedding, 19 August: 9.6 µg/m³, 1.6× usualRedding, 20 August: 9.3 µg/m³, 1.5× usualRedding, 21 August: 15.0 µg/m³, 2.5× usualRedding, 22 August: 16.3 µg/m³, 2.7× usualRedding, 23 August: 10.3 µg/m³, 1.7× usualRedding, 24 August: 8.0 µg/m³, 1.3× usualRedding, 25 August: 8.0 µg/m³, 1.3× usualRedding, 26 August: 5.1 µg/m³, 0.8× usualRedding, 27 August: 4.9 µg/m³, 0.8× usualRedding, 28 August: 16.2 µg/m³, 2.7× usualRedding, 29 August: 52.5 µg/m³, 8.6× usualRedding, 30 August: 21.9 µg/m³, 3.6× usualRedding, 31 August: 38.6 µg/m³, 6.3× usualRedding, 1 September: 11.6 µg/m³, 1.9× usualRedding, 2 September: 3.7 µg/m³, 0.6× usualRedding, 3 September: 5.8 µg/m³, 1.0× usualUkiahUkiah, 14 August: 7.3 µg/m³, 1.3× usualUkiah, 15 August: 9.8 µg/m³, 1.8× usualUkiah, 16 August: 7.8 µg/m³, 1.4× usualUkiah, 17 August: 10.5 µg/m³, 1.9× usualUkiah, 18 August: 3.9 µg/m³, 0.7× usualUkiah, 19 August: 8.1 µg/m³, 1.5× usualUkiah, 20 August: 12.1 µg/m³, 2.2× usualUkiah, 21 August: 20.3 µg/m³, 3.7× usualUkiah, 22 August: 9.2 µg/m³, 1.7× usualUkiah, 23 August: 8.7 µg/m³, 1.6× usualUkiah, 24 August: 10.0 µg/m³, 1.8× usualUkiah, 25 August: 15.5 µg/m³, 2.8× usualUkiah, 26 August: no readingUkiah, 27 August: no readingUkiah, 28 August: no readingUkiah, 29 August: 12.9 µg/m³, 2.3× usualUkiah, 30 August: 47.2 µg/m³, 8.6× usualUkiah, 31 August: 35.6 µg/m³, 6.5× usualUkiah, 1 September: 1.9 µg/m³, 0.3× usualUkiah, 2 September: 3.9 µg/m³, 0.7× usualUkiah, 3 September: 6.7 µg/m³, 1.2× usual14 Aug17202326291 Sep
The 60 cities with the highest readings of 110, 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
KamloopsBritish Columbia, Canada8 597.021 August10.955×
Grants PassOregon, United States13 214.027 August4.243×
RoseburgOregon, United States8 202.027 August3.740×
Tri-CitiesWashington, United States3 211.521 August5.836×
PentictonBritish Columbia, Canada9 251.020 August7.036×
Walla WallaWashington, United States4 226.020 August7.032×
PascoWashington, United States3 157.021 August4.531×
KelownaBritish Columbia, Canada8 267.020 August8.930×
The DallesOregon, United States5 174.020 August5.830×
AshlandOregon, United States15 149.028 August5.129×
HermistonOregon, United States3 195.021 August7.028×
SpokaneWashington, United States5 256.019 August9.228×
WenatcheeWashington, United States3 163.021 August5.928×
MedfordOregon, United States15 160.028 August5.828×
Spokane ValleyWashington, United States4 237.019 August9.026×
Moses LakeWashington, United States5 192.020 August7.625×
EllensburgWashington, United States3 145.020 August6.223×
PendletonOregon, United States4 180.020 August7.723×
VernonBritish Columbia, Canada8 201.020 August9.721×
BendOregon, United States12 154.528 August7.521×
YakimaWashington, United States3 141.021 August7.020×
SunnysideWashington, United States4 158.021 August7.920×
ChilliwackBritish Columbia, Canada5 115.020 August6.418×
PullmanWashington, United States3 147.020 August8.617×
EdmontonAlberta, Canada1 201.03 September13.215×
Coeur d'AleneIdaho, United States4 142.019 August9.814×
RedmondOregon, United States12 157.021 August11.214×
CranbrookBritish Columbia, Canada5 104.017 August8.412×
IssaquahWashington, United States4 60.720 August3.712×
AuburnWashington, United States3 70.520 August5.912×
CoquitlamBritish Columbia, Canada3 62.520 August5.312×
LewistonIdaho, United States5 123.020 August10.612×
ShorelineWashington, United States3 59.320 August5.211×
AltamontOregon, United States8 63.228 August5.611×
ParklandWashington, United States2 56.220 August4.211×
EugeneOregon, United States4 59.615 August5.411×
MoscowIdaho, United States4 106.020 August10.310×
Red DeerAlberta, Canada1 111.73 September11.010×
TacomaWashington, United States2 52.620 August5.49.7×
OrchardsWashington, United States2 48.420 August2.39.7×
SquamishBritish Columbia, Canada4 69.220 August7.39.5×
CanbyOregon, United States1 44.720 August4.98.9×
Columbia CityWashington, United States3 60.320 August6.98.7×
RentonWashington, United States4 52.320 August6.08.7×
West VancouverBritish Columbia, Canada3 45.020 August5.28.7×
ReddingCalifornia, United States2 52.529 August6.18.6×
UkiahCalifornia, United States2 47.230 August5.58.6×
GreshamOregon, United States1 41.520 August4.48.3×
BremertonWashington, United States2 41.020 August4.78.2×
HillsboroOregon, United States1 40.020 August3.98.0×
BellevueWashington, United States1 39.620 August4.57.9×
Salmon CreekWashington, United States1 39.420 August4.87.9×
Forest GroveOregon, United States1 39.220 August3.17.8×
BeavertonOregon, United States1 39.020 August4.17.8×
PortlandOregon, United States1 38.620 August4.47.7×
LangfordBritish Columbia, Canada4 38.220 August4.87.6×
SeattleWashington, United States3 45.720 August6.27.4×
BurnabyBritish Columbia, Canada3 39.720 August5.47.4×
CentraliaWashington, United States1 36.720 August4.37.3×
VancouverWashington, United States1 36.020 August4.07.2×
AlbanyOregon, United States2 35.820 August3.97.2×
LangleyBritish Columbia, Canada4 35.925 August5.17.0×
Port CoquitlamBritish Columbia, Canada2 36.520 August5.27.0×
AbbotsfordBritish Columbia, Canada4 39.720 August5.77.0×
TigardOregon, United States1 40.320 August5.86.9×
Strawberry HillBritish Columbia, Canada3 36.726 August5.36.9×
SalemOregon, United States1 34.620 August4.26.9×
SacramentoCalifornia, United States2 35.330 August5.26.8×
Port AngelesWashington, United States2 33.920 August4.56.8×
WoodburnOregon, United States1 33.720 August3.46.7×
North VancouverBritish Columbia, Canada3 35.125 August5.36.6×
AirdrieAlberta, Canada1 58.53 September9.06.5×
CourtenayBritish Columbia, Canada2 32.427 August2.86.5×
Port AlberniBritish Columbia, Canada1 31.720 August4.86.3×
MilwaukieOregon, United States1 31.120 August3.96.2×
McMinnvilleOregon, United States1 30.620 August3.36.1×
NanaimoBritish Columbia, Canada1 30.227 August4.76.0×
DuncanBritish Columbia, Canada2 29.820 August5.06.0×
LongviewWashington, United States1 29.720 August4.45.9×
HarewoodBritish Columbia, Canada2 29.627 August4.95.9×
VictoriaBritish Columbia, Canada2 32.526 August5.65.8×
DallasOregon, United States1 29.020 August2.75.8×
ModestoCalifornia, United States2 34.030 August5.95.8×
TracyCalifornia, United States1 28.630 August5.05.7×
VancouverBritish Columbia, Canada2 30.226 August5.35.7×
WoodlandCalifornia, United States2 35.330 August6.25.7×
GaltCalifornia, United States2 31.130 August5.65.6×
DeltaBritish Columbia, Canada2 27.326 August4.15.5×
CorvallisOregon, United States1 27.220 August3.35.4×
BellinghamWashington, United States3 30.926 August5.75.4×
Santa RosaCalifornia, United States1 26.830 August2.45.4×
MantecaCalifornia, United States1 32.730 August6.35.2×
LaceyWashington, United States1 25.720 August3.25.1×
StocktonCalifornia, United States2 33.430 August6.55.1×
Campbell RiverBritish Columbia, Canada2 25.526 August2.85.1×
ChicoCalifornia, United States1 32.129 August6.35.1×
RichmondBritish Columbia, Canada1 25.227 August4.95.0×
TurlockCalifornia, United States2 37.931 August7.65.0×
CalgaryAlberta, Canada2 62.73 September12.65.0×
Arden-ArcadeCalifornia, United States1 26.330 August5.54.8×
MercedCalifornia, United States2 32.031 August6.94.6×
OaklandCalifornia, United States1 25.530 August5.64.6×
Yuba CityCalifornia, United States1 30.830 August7.04.4×
HelenaMontana, United States1 41.117 August9.64.3×
LethbridgeAlberta, Canada1 39.817 August9.34.3×
San JoseCalifornia, United States2 29.031 August7.34.0×
Medicine HatAlberta, Canada1 32.317 August8.83.7×
ButteMontana, United States1 29.317 August8.33.5×
BoiseIdaho, United States1 29.319 August9.03.3×
MaderaCalifornia, United States2 26.031 August9.32.8×

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 5 of 45 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 45.

Use this page

SmogRank, North-western United States and Canada, August 2023: 110 cities with PM2.5 at twice their usual or more, 17 to 31 August 2023, smogrank.com/episodes/2023-08-north-western-united-states-and-canada (accessed 2 October 2026).

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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.