SmogRank / History / August 27, 2023

Most polluted cities on August 27, 2023

1,370 cities ranked by their average PM2.5 over the day; the worst was Piedras Negras, Mexico, at 986.0 µg/m³. Each city's own local calendar day.

Bad-air episodes during August 27, 2023. All episodes.

← Piedras Negras 986.0 µg/m³ 900 µg/m³15 WHO 24-hour guideline
Every city ranked for August 27, 2023, one column each, worst on the left and cleanest on the right; height is PM2.5 in µg/m³. Point at it to read a city; tap to open it.
  1. 1Piedras NegrasCoahuila, Mexico
    500+65.7×
  2. 2Grants PassOregon, United States
    28914.3×
  3. 3RoseburgOregon, United States
    27713.5×
  4. 4Fort McMurrayAlberta, Canada
    26812.9×
  5. 5OsornoLos Lagos Region, Chile
    24911.6×
  6. 6Puerto VarasLos Lagos Region, Chile
    2219.7×
  7. 7MedfordOregon, United States
    2149.3×
  8. 8AshlandOregon, United States
    2038.5×
  9. 9NacimientoBiobio, Chile
    1856.9×
  10. 10Los ÁngelesBiobio, Chile
    1846.9×
  11. 11ChillánÑuble, Chile
    1796.4×
  12. 12BendOregon, United States
    1725.7×
  13. 13San CarlosÑuble, Chile
    1705.5×
  14. 14CuranilahueBiobio, Chile
    1675.2×
  15. 15Kampalalow-cost sensorsCentral Region, Uganda
    1655.0×
  16. 16ValdiviaLos Ríos Region, Chile
    1574.3×
  17. 17AlexandriaAlexandria, Egypt
    1574.3×
  18. 18TemucoAraucania, Chile
    1554.1×
  19. 19La UniónLos Ríos Region, Chile
    1533.9×
  20. 20Lahorelow-cost sensorsPunjab, Pakistan
    1523.8×
  21. 21TalcahuanoBiobio, Chile
    1523.8×
  22. 22CuricóMaule Region, Chile
    1523.8×
  23. 23EdmontonAlberta, Canada
    1523.8×
  24. 24Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    1463.6×
  25. 25Dhakalow-cost sensorsDhaka Division, Bangladesh
    1443.5×
  26. 26ToméBiobio, Chile
    1363.3×
  27. 27TalcaMaule Region, Chile
    1343.3×
  28. 27Grande PrairieAlberta, Canada
    1343.3×
  29. 29TalaganteSantiago Metropolitan, Chile
    1333.2×
  30. 30ChilliwackBritish Columbia, Canada
    1323.2×
  31. 31DelhiDelhi, India
    1303.1×
  32. 32Fort St. JohnBritish Columbia, Canada
    1293.1×
  33. 33SantiagoSantiago Metropolitan, Chile
    1283.1×
  34. 34Prince AlbertSaskatchewan, Canada
    1273.1×
  35. 35KolkataWest Bengal, India
    1253.0×
  36. 36HualquiBiobio, Chile
    1253.0×
  37. 37CoronelBiobio, Chile
    1212.9×
  38. 38The DallesOregon, United States
    1182.8×
  39. 39Puerto AysénAysén, Chile
    1102.6×
  40. 40RedmondOregon, United States
    1082.6×
  41. 41DushanbeDushanbe, Tajikistan
    1042.4×
  42. 42RengoO'Higgins Region, Chile
    1032.4×
  43. 43San Salvador TizatlalliMéxico, Mexico
    1022.4×
  44. 44ConcepciónBiobio, Chile
    1002.4×
  45. 45San Pedro de la PazBiobio, Chile
    992.3×
  46. 46IssaquahWashington, United States
    992.3×
  47. 47KamloopsBritish Columbia, Canada
    982.3×
  48. 48Şabāḩ as SālimMubārak al Kabīr, Kuwait
    982.3×
  49. 49KigaliKigali, Rwanda
    982.3×
  50. 50PristinaPristina, Kosovo
    972.3×
  51. 51XonacatlánMéxico, Mexico
    972.2×
  52. 52Puente AltoSantiago Metropolitan, Chile
    962.2×
  53. 53SaskatoonSaskatchewan, Canada
    962.2×
  54. 54Puerto MonttLos Lagos Region, Chile
    952.2×
  55. 55ChiguayanteBiobio, Chile
    952.2×
  56. 56CourtenayBritish Columbia, Canada
    942.2×
  57. 57Islamabadlow-cost sensorsIslamabad, Pakistan
    942.1×
  58. 57RancaguaO'Higgins Region, Chile
    942.1×
  59. 59ReginaSaskatchewan, Canada
    932.1×
  60. 60PentictonBritish Columbia, Canada
    932.1×
  61. 61SarajevoFederation of B&H, Bosnia and Herzegovina
    922.1×
  62. 62TolucaMéxico, Mexico
    912.0×
  63. 63MexicaliBaja California, Mexico
    902.0×
  64. 63NanaimoBritish Columbia, Canada
    902.0×
  65. 65CuernavacaMorelos, Mexico
    902.0×
  66. 65TerraceBritish Columbia, Canada
    902.0×
  67. 67CauquenesMaule Region, Chile
    902.0×
  68. 68AbbotsfordBritish Columbia, Canada
    902.0×
  69. 68Red DeerAlberta, Canada
    902.0×
  70. 70HarewoodBritish Columbia, Canada
    892.0×
  71. 71New OrleansLouisiana, United States
    892.0×
  72. 72QuillotaValparaiso, Chile
    881.9×
  73. 72CopiapóAtacama, Chile
    881.9×
  74. 74Baton RougeLouisiana, United States
    881.9×
  75. 75HanoiHanoi, Vietnam
    881.9×
  76. 75St. AlbertAlberta, Canada
    881.9×
  77. 77Sherwood ParkAlberta, Canada
    871.9×
  78. 78CoyhaiqueAysén, Chile
    861.9×
  79. 79ShorelineWashington, United States
    851.8×
  80. 80BellinghamWashington, United States
    851.8×
  81. 81AntofagastaAntofagasta, Chile
    841.8×
  82. 82SeattleWashington, United States
    841.8×
  83. 83Addis AbabaAddis Ababa, Ethiopia
    841.8×
  84. 83ChennaiTamil Nadu, India
    841.8×
  85. 85VictoriaBritish Columbia, Canada
    831.8×
  86. 86VancouverBritish Columbia, Canada
    831.7×
  87. 87KelownaBritish Columbia, Canada
    821.7×
  88. 87Strawberry HillBritish Columbia, Canada
    821.7×
  89. 89BeijingBeijing, China
    821.7×
  90. 89PécsBaranya, Hungary
    821.7×
  91. 89LangleyBritish Columbia, Canada
    821.7×
  92. 89Swift CurrentSaskatchewan, Canada
    821.7×
  93. 93Campbell RiverBritish Columbia, Canada
    811.7×
  94. 94CoquimboCoquimbo Region, Chile
    811.7×
  95. 95DeltaBritish Columbia, Canada
    811.7×
  96. 95DuncanBritish Columbia, Canada
    811.7×
  97. 95LangfordBritish Columbia, Canada
    811.7×
  98. 95RichmondBritish Columbia, Canada
    811.7×
  99. 99RentonWashington, United States
    811.7×
  100. 100San Francisco TlalcilalcalpanMéxico, Mexico
    811.7×
  101. 101HattiesburgMississippi, United States
    801.6×
  102. 102Ciudad JuárezChihuahua, Mexico
    801.6×
  103. 102Columbia CityWashington, United States
    801.6×
  104. 104QuinteroValparaiso, Chile
    801.6×
  105. 105AuburnWashington, United States
    791.6×
  106. 106EugeneOregon, United States
    791.6×
  107. 107VernonBritish Columbia, Canada
    791.6×
  108. 108La SerenaCoquimbo Region, Chile
    791.6×
  109. 109Victoria de DurangoDurango, Mexico
    781.6×
  110. 109West VancouverBritish Columbia, Canada
    781.6×
  111. 111SquamishBritish Columbia, Canada
    771.6×
  112. 112LotaBiobio, Chile
    771.5×
  113. 113BellevueWashington, United States
    771.5×
  114. 114TlaquepaqueJalisco, Mexico
    771.5×
  115. 114North CowichanBritish Columbia, Canada
    771.5×
  116. 116MiskolcBorsod-Abaúj-Zemplén, Hungary
    761.5×
  117. 117BamakoBamako, Mali
    761.5×
  118. 118Samut SakhonSamut Sakhon, Thailand
    751.5×
  119. 118CoquitlamBritish Columbia, Canada
    751.5×
  120. 120ConcónValparaiso, Chile
    751.5×
  121. 121JeddahMecca Region, Saudi Arabia
    741.4×
  122. 121TijuanaBaja California, Mexico
    741.4×
  123. 121BurnabyBritish Columbia, Canada
    741.4×
  124. 121North VancouverBritish Columbia, Canada
    741.4×
  125. 125Ulu BedokSingapore
    741.4×
  126. 125CalgaryAlberta, Canada
    741.4×
  127. 127ZapopanJalisco, Mexico
    731.4×
  128. 127RichmondCalifornia, United States
    731.4×
  129. 129Banja LukaSrpska, Bosnia and Herzegovina
    731.4×
  130. 129SulphurLouisiana, United States
    731.4×
  131. 131SalinasCalifornia, United States
    731.4×
  132. 132AltamontOregon, United States
    721.4×
  133. 132Port AlberniBritish Columbia, Canada
    721.4×
  134. 134Salmon CreekWashington, United States
    721.4×
  135. 135ShreveportLouisiana, United States
    721.3×
  136. 136TigardOregon, United States
    711.3×
  137. 137Karachilow-cost sensorsSindh, Pakistan
    711.3×
  138. 137Nong KhaemBangkok, Thailand
    711.3×
  139. 137JacksonMississippi, United States
    711.3×
  140. 140SzegedCsongrád, Hungary
    711.3×
  141. 140GuadalajaraJalisco, Mexico
    711.3×
  142. 140CentraliaWashington, United States
    711.3×
  143. 143Medicine HatAlberta, Canada
    711.3×
  144. 143Port CoquitlamBritish Columbia, Canada
    711.3×
  145. 145Ferry PassFlorida, United States
    701.3×
  146. 145PascagoulaMississippi, United States
    701.3×
  147. 147BremertonWashington, United States
    701.3×
  148. 148Wan ChaiWan Chai, Hong Kong
    691.3×
  149. 149Mount VernonWashington, United States
    691.2×
  150. 150Viña del MarValparaiso, Chile
    691.2×
  151. 151GuangzhouGuangdong, China
    691.2×
  152. 151AberdeenWashington, United States
    691.2×
  153. 153BakuBaki, Azerbaijan
    681.2×
  154. 153TocopillaAntofagasta, Chile
    681.2×
  155. 153Alto HospicioTarapacá, Chile
    681.2×
  156. 156CanbyOregon, United States
    681.2×
  157. 157Ang Mo Kio New TownSingapore
    681.2×
  158. 157BirminghamAlabama, United States
    681.2×
  159. 157TacomaWashington, United States
    681.2×
  160. 160HillsboroOregon, United States
    671.2×
  161. 160AirdrieAlberta, Canada
    671.2×
  162. 162CasertaCampania, Italy
    671.2×
  163. 162PortlandOregon, United States
    671.2×
  164. 162Moses LakeWashington, United States
    671.2×
  165. 165ParklandWashington, United States
    671.2×
  166. 165SpokaneWashington, United States
    671.2×
  167. 167MidwayFlorida, United States
    661.2×
  168. 168Phra PradaengSamut Prakan, Thailand
    661.1×
  169. 168AlgiersAlgiers, Algeria
    661.1×
  170. 168LibertyMissouri, United States
    661.1×
  171. 168AnacortesWashington, United States
    661.1×
  172. 172GulfportMississippi, United States
    661.1×
  173. 172GreshamOregon, United States
    661.1×
  174. 174NairobiNairobi County, Kenya
    651.1×
  175. 175Bang Bo DistrictSamut Prakan, Thailand
    651.1×
  176. 175N'DjamenaN’Djaména, Chad
    651.1×
  177. 177ComptonCalifornia, United States
    651.1×
  178. 178Forest GroveOregon, United States
    651.1×
  179. 178HermistonOregon, United States
    651.1×
  180. 180CelayaGuanajuato, Mexico
    641.1×
  181. 180FairhopeAlabama, United States
    641.1×
  182. 180Chula VistaCalifornia, United States
    641.1×
  183. 180CranbrookBritish Columbia, Canada
    641.1×
  184. 184CalamaAntofagasta, Chile
    641.1×
  185. 184PrichardAlabama, United States
    641.1×
  186. 184AlbanyOregon, United States
    641.1×
  187. 187IwataShizuoka, Japan
    641.1×
  188. 187BeavertonOregon, United States
    641.1×
  189. 187LongviewWashington, United States
    641.1×
  190. 190OrchardsWashington, United States
    631.0×
  191. 190Port AngelesWashington, United States
    631.0×
  192. 192AmmanAmman, Jordan
    631.0×
  193. 193AntananarivoAnalamanga, Madagascar
    631.0×
  194. 193FujiedaShizuoka, Japan
    631.0×
  195. 193ColumbusGeorgia, United States
    631.0×
  196. 196Coeur d'AleneIdaho, United States
    631.0×
  197. 197AlbanyGeorgia, United States
    631.0×
  198. 198Santa CatarinaNuevo León, Mexico
    621.0×
  199. 198Arroyo GrandeCalifornia, United States
    621.0×
  200. 198Great FallsMontana, United States
    621.0×

Top 200 of 1,370 shown.

Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

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SmogRank, most polluted cities, PM2.5, August 27, 2023, smogrank.com/history/2023-08-27 (accessed 2 Oct 2026).

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