SmogRank / History / July 23, 2023

Most polluted cities on July 23, 2023

1,294 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 July 23, 2023. All episodes.

← Piedras Negras 986.0 µg/m³ 900 µg/m³15 WHO 24-hour guideline
Every city ranked for July 23, 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. 2Puerto VarasLos Lagos Region, Chile
    24911.6×
  3. 3OsornoLos Lagos Region, Chile
    2139.2×
  4. 4CoyhaiqueAysén, Chile
    1715.6×
  5. 5Puerto MonttLos Lagos Region, Chile
    1715.6×
  6. 6TalcahuanoBiobio, Chile
    1685.3×
  7. 7CuranilahueBiobio, Chile
    1645.0×
  8. 8HualpénBiobio, Chile
    1634.8×
  9. 9NacimientoBiobio, Chile
    1624.8×
  10. 10Kampalalow-cost sensorsCentral Region, Uganda
    1624.7×
  11. 11DushanbeDushanbe, Tajikistan
    1584.4×
  12. 12XonacatlánMéxico, Mexico
    1554.1×
  13. 13Puerto AysénAysén, Chile
    1544.0×
  14. 14YumaArizona, United States
    1544.0×
  15. 15La UniónLos Ríos Region, Chile
    1544.0×
  16. 15Fort McMurrayAlberta, Canada
    1544.0×
  17. 17CoronelBiobio, Chile
    1393.4×
  18. 18SaskatoonSaskatchewan, Canada
    1333.2×
  19. 19Saint CloudMinnesota, United States
    1293.1×
  20. 20CuricóMaule Region, Chile
    1273.1×
  21. 21RancaguaO'Higgins Region, Chile
    1243.0×
  22. 22DuluthMinnesota, United States
    1233.0×
  23. 23IndioCalifornia, United States
    1222.9×
  24. 24Lahorelow-cost sensorsPunjab, Pakistan
    1222.9×
  25. 25El CentroCalifornia, United States
    1182.8×
  26. 26SuperiorWisconsin, United States
    1152.7×
  27. 27MinneapolisMinnesota, United States
    1142.7×
  28. 28ValdiviaLos Ríos Region, Chile
    1132.7×
  29. 29MexicaliBaja California, Mexico
    1132.7×
  30. 30Saint PaulMinnesota, United States
    1122.7×
  31. 31HualquiBiobio, Chile
    1122.7×
  32. 32TalcaMaule Region, Chile
    1112.6×
  33. 33ChillánÑuble, Chile
    1112.6×
  34. 34San CarlosÑuble, Chile
    1112.6×
  35. 35TemucoAraucania, Chile
    1102.6×
  36. 36CauquenesMaule Region, Chile
    1072.5×
  37. 37PristinaPristina, Kosovo
    1072.5×
  38. 38SantiagoSantiago Metropolitan, Chile
    1062.5×
  39. 39Santa Anita - Los FicusLima region, Peru
    1052.5×
  40. 40TalaganteSantiago Metropolitan, Chile
    1052.5×
  41. 40BrandonManitoba, Canada
    1052.5×
  42. 42RengoO'Higgins Region, Chile
    1042.5×
  43. 43Dhakalow-cost sensorsDhaka Division, Bangladesh
    1032.4×
  44. 44Eau ClaireWisconsin, United States
    1022.4×
  45. 45Saint MichaelMinnesota, United States
    1002.4×
  46. 46BrawleyCalifornia, United States
    992.3×
  47. 47San Pedro de la PazBiobio, Chile
    982.3×
  48. 48Los ÁngelesBiobio, Chile
    962.2×
  49. 49BlaineMinnesota, United States
    962.2×
  50. 50ReginaSaskatchewan, Canada
    952.2×
  51. 51ToméBiobio, Chile
    952.2×
  52. 52SalorTashkent Region, Uzbekistan
    942.2×
  53. 53BurnsvilleMinnesota, United States
    942.1×
  54. 54ShakopeeMinnesota, United States
    932.1×
  55. 55KamloopsBritish Columbia, Canada
    912.0×
  56. 56CoquimboCoquimbo Region, Chile
    902.0×
  57. 57AsprópyrgosAttica, Greece
    892.0×
  58. 58AlgiersAlgiers, Algeria
    892.0×
  59. 59ConcepciónBiobio, Chile
    881.9×
  60. 60AthensAttica, Greece
    881.9×
  61. 61LinaresMaule Region, Chile
    871.9×
  62. 62West FargoNorth Dakota, United States
    861.8×
  63. 63Puente AltoSantiago Metropolitan, Chile
    851.8×
  64. 63CalexicoCalifornia, United States
    851.8×
  65. 65Apple ValleyMinnesota, United States
    841.8×
  66. 65EdmontonAlberta, Canada
    841.8×
  67. 65Red DeerAlberta, Canada
    841.8×
  68. 68MostaIl-Mosta, Malta
    831.7×
  69. 69SarajevoFederation of B&H, Bosnia and Herzegovina
    821.7×
  70. 70Şabāḩ as SālimMubārak al Kabīr, Kuwait
    821.7×
  71. 71CalgaryAlberta, Canada
    821.7×
  72. 72CopiapóAtacama, Chile
    801.6×
  73. 73SliemaTas-Sliema, Malta
    801.6×
  74. 73CelayaGuanajuato, Mexico
    801.6×
  75. 75ChennaiTamil Nadu, India
    781.6×
  76. 76LimaLima Province, Peru
    781.6×
  77. 76Ciudad JuárezChihuahua, Mexico
    781.6×
  78. 78QuillotaValparaiso, Chile
    771.6×
  79. 78Swift CurrentSaskatchewan, Canada
    771.6×
  80. 80WatertownSouth Dakota, United States
    771.5×
  81. 81Bonita SpringsFlorida, United States
    771.5×
  82. 82PiraeusAttica, Greece
    771.5×
  83. 82BakuBaki, Azerbaijan
    771.5×
  84. 82LotaBiobio, Chile
    771.5×
  85. 85La SerenaCoquimbo Region, Chile
    761.5×
  86. 86San Francisco De BorjaLima region, Peru
    761.5×
  87. 87AcharnésAttica, Greece
    761.5×
  88. 88QuinteroValparaiso, Chile
    751.5×
  89. 89ŻabbarĦaż-Żabbar, Malta
    751.5×
  90. 89AntofagastaAntofagasta, Chile
    751.5×
  91. 91Karachilow-cost sensorsSindh, Pakistan
    751.5×
  92. 92KhalándrionAttica, Greece
    741.4×
  93. 92TijuanaBaja California, Mexico
    741.4×
  94. 94AricaArica y Parinacota Region, Chile
    741.4×
  95. 95BakersfieldCalifornia, United States
    741.4×
  96. 96BeijingBeijing, China
    741.4×
  97. 97Villa Poeta José Gálvez BarrenecheaLima region, Peru
    731.4×
  98. 98AnkenyIowa, United States
    731.4×
  99. 99Alto HospicioTarapacá, Chile
    731.4×
  100. 100GuadalajaraJalisco, Mexico
    721.4×
  101. 101BamakoBamako, Mali
    721.4×
  102. 102Fort LauderdaleFlorida, United States
    711.3×
  103. 103BrookingsSouth Dakota, United States
    711.3×
  104. 104Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    711.3×
  105. 105AntananarivoAnalamanga, Madagascar
    711.3×
  106. 106BeneventoCampania, Italy
    701.3×
  107. 106AirdrieAlberta, Canada
    701.3×
  108. 108TocopillaAntofagasta, Chile
    701.3×
  109. 109HanoiHanoi, Vietnam
    701.3×
  110. 110HomesteadFlorida, United States
    691.3×
  111. 111DelhiDelhi, India
    691.3×
  112. 112CuencaCastille-La Mancha, Spain
    691.3×
  113. 112NaplesCampania, Italy
    691.3×
  114. 112CalamaAntofagasta, Chile
    691.3×
  115. 115Des MoinesIowa, United States
    691.2×
  116. 115AppletonWisconsin, United States
    691.2×
  117. 117BitolaBitola, North Macedonia
    681.2×
  118. 117Jurupa ValleyCalifornia, United States
    681.2×
  119. 119PesaroThe Marches, Italy
    681.2×
  120. 120ToledoCastille-La Mancha, Spain
    681.2×
  121. 120IndianapolisIndiana, United States
    681.2×
  122. 120UkiahCalifornia, United States
    681.2×
  123. 123BelmopanCayo District, Belize
    671.2×
  124. 124DębicaSubcarpathia, Poland
    671.2×
  125. 124West MifflinPennsylvania, United States
    671.2×
  126. 126TolucaMéxico, Mexico
    671.2×
  127. 126Le RobertMartinique, Martinique
    671.2×
  128. 128Bang Bo DistrictSamut Prakan, Thailand
    661.2×
  129. 129Le LamentinMartinique, Martinique
    661.2×
  130. 129RiversideCalifornia, United States
    661.2×
  131. 131Falconara MarittimaThe Marches, Italy
    661.1×
  132. 131Fort-de-FranceMartinique, Martinique
    661.1×
  133. 131ConcónValparaiso, Chile
    661.1×
  134. 134KavadarciKavadarci, North Macedonia
    661.1×
  135. 134ModugnoApulia, Italy
    661.1×
  136. 134LansingMichigan, United States
    661.1×
  137. 134BanningCalifornia, United States
    661.1×
  138. 134Great FallsMontana, United States
    661.1×
  139. 139DavieFlorida, United States
    661.1×
  140. 139VisaliaCalifornia, United States
    661.1×
  141. 141Viña del MarValparaiso, Chile
    651.1×
  142. 141DearbornMichigan, United States
    651.1×
  143. 141AberdeenSouth Dakota, United States
    651.1×
  144. 141Santa ClaritaCalifornia, United States
    651.1×
  145. 145Yuba CityCalifornia, United States
    651.1×
  146. 146Los AngelesCalifornia, United States
    651.1×
  147. 147MiamiFlorida, United States
    651.1×
  148. 148NišCentral Serbia, Serbia
    641.1×
  149. 149Coconut CreekFlorida, United States
    641.1×
  150. 149La CrosseWisconsin, United States
    641.1×
  151. 151Khlong LuangPathum Thani, Thailand
    641.1×
  152. 151Abidjanlow-cost sensorsAbidjan Autonomous District, Ivory Coast
    641.1×
  153. 151FontanaCalifornia, United States
    641.1×
  154. 154Civitanova MarcheThe Marches, Italy
    641.1×
  155. 154KitchenerOntario, Canada
    641.1×
  156. 156GuangzhouGuangdong, China
    631.1×
  157. 156Lagoslow-cost sensorsLagos, Nigeria
    631.1×
  158. 156Castelló de la PlanaValencia, Spain
    631.1×
  159. 156AnconaThe Marches, Italy
    631.1×
  160. 156FresnoCalifornia, United States
    631.1×
  161. 161SalamancaGuanajuato, Mexico
    631.0×
  162. 162Belle GladeFlorida, United States
    631.0×
  163. 162VeniceFlorida, United States
    631.0×
  164. 164Ang Mo Kio New TownSingapore
    631.0×
  165. 164Palm CityFlorida, United States
    631.0×
  166. 164KalamazooMichigan, United States
    631.0×
  167. 164Green BayWisconsin, United States
    631.0×
  168. 164SunnysideWashington, United States
    631.0×
  169. 169Queenstown Estatelow-cost sensorsSingapore
    621.0×
  170. 169TorreviejaValencia, Spain
    621.0×
  171. 169Tepeji del Río de OcampoHidalgo, Mexico
    621.0×
  172. 172Kathmandulow-cost sensorsBagmati Province, Nepal
    621.0×
  173. 172WestonFlorida, United States
    621.0×
  174. 172OmahaNebraska, United States
    621.0×
  175. 172PortervilleCalifornia, United States
    621.0×
  176. 176Delray BeachFlorida, United States
    621.0×
  177. 176WellingtonFlorida, United States
    621.0×
  178. 176GlendoraCalifornia, United States
    621.0×
  179. 179CantonOhio, United States
    621.0×
  180. 179MadisonWisconsin, United States
    621.0×
  181. 181ChiguayanteBiobio, Chile
    611.0×
  182. 181ClevelandOhio, United States
    611.0×
  183. 183ThessaloníkiCentral Macedonia, Greece
    611.0×
  184. 183SalernoCampania, Italy
    611.0×
  185. 183BellevueNebraska, United States
    611.0×
  186. 183HanfordCalifornia, United States
    611.0×
  187. 187RoveretoTrentino-Alto Adige, Italy
    611.0×
  188. 187IrapuatoGuanajuato, Mexico
    611.0×
  189. 189TetovoTetovo, North Macedonia
    611.0×
  190. 189Deerfield BeachFlorida, United States
    611.0×
  191. 189ClovisCalifornia, United States
    611.0×
  192. 189Santa BarbaraCalifornia, United States
    611.0×
  193. 189Sherwood ParkAlberta, Canada
    611.0×
  194. 194BurbankCalifornia, United States
    611.0×
  195. 194MaderaCalifornia, United States
    611.0×
  196. 194Simi ValleyCalifornia, United States
    611.0×
  197. 197LitvínovÚstí nad Labem Region, Czechia
    610.9×
  198. 197LancasterPennsylvania, United States
    610.9×
  199. 197St. AlbertAlberta, Canada
    610.9×
  200. 200Santa CatarinaNuevo León, Mexico
    600.9×

Top 200 of 1,294 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

Use this board

SmogRank, most polluted cities, PM2.5, July 23, 2023, smogrank.com/history/2023-07-23 (accessed 2 Oct 2026).

Download top 10 (PNG)

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