SmogRank / History / July 20, 2023

Most polluted cities on July 20, 2023

1,418 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 20, 2023. All episodes.

← Piedras Negras 986.0 µg/m³ 900 µg/m³15 WHO 24-hour guideline
Every city ranked for July 20, 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. 2DushanbeDushanbe, Tajikistan
    26612.8×
  3. 3CoyhaiqueAysén, Chile
    2199.6×
  4. 4CranbrookBritish Columbia, Canada
    1745.9×
  5. 5LinaresMaule Region, Chile
    1735.8×
  6. 6TalaganteSantiago Metropolitan, Chile
    1655.0×
  7. 7RancaguaO'Higgins Region, Chile
    1644.9×
  8. 8CuricóMaule Region, Chile
    1624.7×
  9. 9SantiagoSantiago Metropolitan, Chile
    1614.7×
  10. 10Lahorelow-cost sensorsPunjab, Pakistan
    1604.6×
  11. 11Grande PrairieAlberta, Canada
    1594.5×
  12. 12Puerto AysénAysén, Chile
    1594.4×
  13. 13RengoO'Higgins Region, Chile
    1584.3×
  14. 14NacimientoBiobio, Chile
    1564.2×
  15. 15ChillánÑuble, Chile
    1544.0×
  16. 16TalcaMaule Region, Chile
    1543.9×
  17. 17AnnecyAuvergne-Rhône-Alpes, France
    1523.8×
  18. 18Fort St. JohnBritish Columbia, Canada
    1453.6×
  19. 19CauquenesMaule Region, Chile
    1403.4×
  20. 20Puente AltoSantiago Metropolitan, Chile
    1343.2×
  21. 21ShenyangLiaoning, China
    1253.0×
  22. 22Los ÁngelesBiobio, Chile
    1222.9×
  23. 23QuillotaValparaiso, Chile
    1192.9×
  24. 24EdmontonAlberta, Canada
    1182.8×
  25. 25HanoiHanoi, Vietnam
    1172.8×
  26. 26HualquiBiobio, Chile
    1162.8×
  27. 27Santa Anita - Los FicusLima region, Peru
    1142.7×
  28. 28BeijingBeijing, China
    1062.5×
  29. 29AlgiersAlgiers, Algeria
    1062.5×
  30. 30CuencaCastille-La Mancha, Spain
    1052.5×
  31. 31JaénAndalusia, Spain
    1052.5×
  32. 32AsprópyrgosAttica, Greece
    1042.4×
  33. 33San CarlosÑuble, Chile
    1012.4×
  34. 34MálagaAndalusia, Spain
    1002.4×
  35. 35Kampalalow-cost sensorsCentral Region, Uganda
    972.3×
  36. 36TlaquepaqueJalisco, Mexico
    962.2×
  37. 37Karachilow-cost sensorsSindh, Pakistan
    952.2×
  38. 38Ciudad ApodacaNuevo León, Mexico
    952.2×
  39. 39AntofagastaAntofagasta, Chile
    942.1×
  40. 39LimaLima Province, Peru
    942.1×
  41. 41TemucoAraucania, Chile
    932.1×
  42. 42PristinaPristina, Kosovo
    932.1×
  43. 43CártamaAndalusia, Spain
    932.1×
  44. 44Dhakalow-cost sensorsDhaka Division, Bangladesh
    922.1×
  45. 44Viña del MarValparaiso, Chile
    922.1×
  46. 46DelhiDelhi, India
    902.0×
  47. 47SaskatoonSaskatchewan, Canada
    902.0×
  48. 48CuranilahueBiobio, Chile
    902.0×
  49. 49ChennaiTamil Nadu, India
    892.0×
  50. 49La SerenaCoquimbo Region, Chile
    892.0×
  51. 51CoquimboCoquimbo Region, Chile
    881.9×
  52. 52GranadaAndalusia, Spain
    871.9×
  53. 52UkiahCalifornia, United States
    871.9×
  54. 54Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    871.9×
  55. 55AlbanyGeorgia, United States
    871.9×
  56. 56ValdiviaLos Ríos Region, Chile
    871.9×
  57. 57MostaIl-Mosta, Malta
    861.9×
  58. 58TrnavaTrnava Region, Slovakia
    861.8×
  59. 59PalmaBalearic Islands, Spain
    851.8×
  60. 59ŻabbarĦaż-Żabbar, Malta
    851.8×
  61. 61ConcónValparaiso, Chile
    851.8×
  62. 62AntananarivoAnalamanga, Madagascar
    841.8×
  63. 63BensalemPennsylvania, United States
    841.8×
  64. 64BailénAndalusia, Spain
    831.8×
  65. 65OsornoLos Lagos Region, Chile
    831.7×
  66. 66SarajevoFederation of B&H, Bosnia and Herzegovina
    831.7×
  67. 67ElizabethNew Jersey, United States
    821.7×
  68. 68MexicaliBaja California, Mexico
    821.7×
  69. 69SpringdaleArkansas, United States
    821.7×
  70. 69Prince AlbertSaskatchewan, Canada
    821.7×
  71. 71HueytownAlabama, United States
    811.7×
  72. 72TrentonNew Jersey, United States
    811.7×
  73. 73Bang NaBangkok, Thailand
    801.7×
  74. 74San Francisco TlalcilalcalpanMéxico, Mexico
    801.6×
  75. 74HualpénBiobio, Chile
    801.6×
  76. 74St. AlbertAlberta, Canada
    801.6×
  77. 77CatañoCataño, Puerto Rico
    801.6×
  78. 77San Francisco De BorjaLima region, Peru
    801.6×
  79. 79Fort LauderdaleFlorida, United States
    791.6×
  80. 80CoronelBiobio, Chile
    791.6×
  81. 80CopiapóAtacama, Chile
    791.6×
  82. 80AshlandOregon, United States
    791.6×
  83. 83Şabāḩ as SālimMubārak al Kabīr, Kuwait
    791.6×
  84. 84Le RobertMartinique, Martinique
    791.6×
  85. 85Alto HospicioTarapacá, Chile
    781.6×
  86. 86Ban Samae DamBangkok, Thailand
    781.6×
  87. 87QuinteroValparaiso, Chile
    771.5×
  88. 88PhiladelphiaPennsylvania, United States
    771.5×
  89. 89Toms RiverNew Jersey, United States
    771.5×
  90. 89LansingMichigan, United States
    771.5×
  91. 91SavannahGeorgia, United States
    771.5×
  92. 92Le LamentinMartinique, Martinique
    761.5×
  93. 93PesaroThe Marches, Italy
    761.5×
  94. 93XonacatlánMéxico, Mexico
    761.5×
  95. 93PennsaukenNew Jersey, United States
    761.5×
  96. 93BethlehemPennsylvania, United States
    761.5×
  97. 93ReginaSaskatchewan, Canada
    761.5×
  98. 98Islamabadlow-cost sensorsIslamabad, Pakistan
    761.5×
  99. 98ValdostaGeorgia, United States
    761.5×
  100. 100BirminghamAlabama, United States
    751.5×
  101. 101Fort McMurrayAlberta, Canada
    751.5×
  102. 102AllentownPennsylvania, United States
    751.5×
  103. 103Nong KhaemBangkok, Thailand
    751.5×
  104. 103MiamiFlorida, United States
    751.5×
  105. 105ModugnoApulia, Italy
    751.5×
  106. 105Puerto VarasLos Lagos Region, Chile
    751.5×
  107. 107EwingNew Jersey, United States
    741.4×
  108. 108Puerto MonttLos Lagos Region, Chile
    741.4×
  109. 108North CharlestonSouth Carolina, United States
    741.4×
  110. 110La UniónLos Ríos Region, Chile
    741.4×
  111. 111Bang Bo DistrictSamut Prakan, Thailand
    741.4×
  112. 111Jersey CityNew Jersey, United States
    741.4×
  113. 113LancasterPennsylvania, United States
    731.4×
  114. 113NorristownPennsylvania, United States
    731.4×
  115. 115BamakoBamako, Mali
    731.4×
  116. 115La Línea de la ConcepciónAndalusia, Spain
    731.4×
  117. 115New BrunswickNew Jersey, United States
    731.4×
  118. 118LindenNew Jersey, United States
    731.4×
  119. 119Fort-de-FranceMartinique, Martinique
    721.4×
  120. 119Little RockArkansas, United States
    721.4×
  121. 119HarrisburgPennsylvania, United States
    721.4×
  122. 119ReadingPennsylvania, United States
    721.4×
  123. 119Khan Na YaoBangkok, Thailand
    721.4×
  124. 124Falconara MarittimaThe Marches, Italy
    721.4×
  125. 124GuadalajaraJalisco, Mexico
    721.4×
  126. 124HoustonTexas, United States
    721.4×
  127. 127TolucaMéxico, Mexico
    721.4×
  128. 127PleasantvilleNew Jersey, United States
    721.4×
  129. 129Warner RobinsGeorgia, United States
    721.4×
  130. 129Saphan SungBangkok, Thailand
    721.4×
  131. 131BeneventoCampania, Italy
    721.3×
  132. 132New York CityNew York, United States
    711.3×
  133. 133MaconGeorgia, United States
    711.3×
  134. 133Sherwood ParkAlberta, Canada
    711.3×
  135. 135Swift CurrentSaskatchewan, Canada
    711.3×
  136. 136Si Maha PhotPrachin Buri, Thailand
    711.3×
  137. 136Ciudad Benito JuárezNuevo León, Mexico
    711.3×
  138. 136LebanonPennsylvania, United States
    711.3×
  139. 139ShreveportLouisiana, United States
    711.3×
  140. 140Phra PradaengSamut Prakan, Thailand
    701.3×
  141. 140AricaArica y Parinacota Region, Chile
    701.3×
  142. 140Phenix CityAlabama, United States
    701.3×
  143. 140VisaliaCalifornia, United States
    701.3×
  144. 144LotaBiobio, Chile
    701.3×
  145. 145TijuanaBaja California, Mexico
    701.3×
  146. 145Coconut CreekFlorida, United States
    701.3×
  147. 145TexarkanaTexas, United States
    701.3×
  148. 145TurlockCalifornia, United States
    701.3×
  149. 145Khlong Sam WaBangkok, Thailand
    701.3×
  150. 150Ciudad JuárezChihuahua, Mexico
    701.3×
  151. 150MooreOklahoma, United States
    701.3×
  152. 150Great FallsMontana, United States
    701.3×
  153. 153San IsidroCanary Islands, Spain
    701.3×
  154. 153Yuba CityCalifornia, United States
    701.3×
  155. 155HomesteadFlorida, United States
    691.3×
  156. 155DallasTexas, United States
    691.3×
  157. 155CarlislePennsylvania, United States
    691.3×
  158. 158TulsaOklahoma, United States
    691.3×
  159. 159ChiguayanteBiobio, Chile
    691.3×
  160. 160NaplesCampania, Italy
    691.2×
  161. 160TocopillaAntofagasta, Chile
    691.2×
  162. 162BaytownTexas, United States
    691.2×
  163. 162PortervilleCalifornia, United States
    691.2×
  164. 164Mission BendTexas, United States
    691.2×
  165. 165Mae SaiChiang Rai, Thailand
    681.2×
  166. 165San RoqueAndalusia, Spain
    681.2×
  167. 165DavieFlorida, United States
    681.2×
  168. 165Missouri CityTexas, United States
    681.2×
  169. 165West MifflinPennsylvania, United States
    681.2×
  170. 170SalorTashkent Region, Uzbekistan
    681.2×
  171. 170Rose HillVirginia, United States
    681.2×
  172. 170Lat KrabangBangkok, Thailand
    681.2×
  173. 173MukdahanMukdahan, Thailand
    681.2×
  174. 173BakersfieldCalifornia, United States
    681.2×
  175. 173MaderaCalifornia, United States
    681.2×
  176. 176TorreviejaValencia, Spain
    681.2×
  177. 176Santa CatarinaNuevo León, Mexico
    681.2×
  178. 176SalamancaGuanajuato, Mexico
    681.2×
  179. 179Nakhon RatchasimaNakhon Ratchasima, Thailand
    681.2×
  180. 179LivornoTuscany, Italy
    681.2×
  181. 181AlgeteMadrid, Spain
    671.2×
  182. 181ConroeTexas, United States
    671.2×
  183. 181PatersonNew Jersey, United States
    671.2×
  184. 184CórdobaAndalusia, Spain
    671.2×
  185. 184les EscaldesEscaldes-Engordany, Andorra
    671.2×
  186. 184MontemurloTuscany, Italy
    671.2×
  187. 184Deerfield BeachFlorida, United States
    671.2×
  188. 188PiraeusAttica, Greece
    671.2×
  189. 188McAlesterOklahoma, United States
    671.2×
  190. 188ChesterPennsylvania, United States
    671.2×
  191. 188AustinTexas, United States
    671.2×
  192. 192KanchanaburiKanchanaburi, Thailand
    671.2×
  193. 192Delray BeachFlorida, United States
    671.2×
  194. 194Alcalá de HenaresMadrid, Spain
    671.2×
  195. 194AdaOklahoma, United States
    671.2×
  196. 194SpringfieldVirginia, United States
    671.2×
  197. 194VictorvilleCalifornia, United States
    671.2×
  198. 198EdmondOklahoma, United States
    661.2×
  199. 198JenksOklahoma, United States
    661.2×
  200. 198ScrantonPennsylvania, United States
    661.2×

Top 200 of 1,418 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, July 20, 2023, smogrank.com/history/2023-07-20 (accessed 2 Oct 2026).

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