SmogRank / World / United States / California / 2024

Most polluted cities in California, United States, 2024

100 cities in California, United States ranked by their average PM2.5 over the 366 days; 92 above the WHO annual guideline (5.0 µg/m³). Worst: Jurupa Valley at 14.3 µg/m³, #266 of 2,052 cities in the world. Cleanest: Solvang at 3.7. A city needs measurements on 70% of the days to be ranked.

OpenAQ's archive, where our readings come from, has almost none for one of these days. Cities in the United States and Europe have it from the EPA's and the European Environment Agency's own records of the same monitors; elsewhere a city's average is over its other days. Why.

OpenAQ's archive, where our readings come from, has almost none from the United States for March 20, 2024: cities in the United States have it from the EPA's own records of the same monitors. Why.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Jurupa Valley 3% 3%0
Every city in California, United States ranked for 2024, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Jurupa Valley
    3%
  2. 2Bakersfield
    3%
  3. 3Fresno
    2%
  4. 4Hanford
    2%
  5. 5Big Bear City
    2%
  6. 6Fontana
    2%
  7. 7Porterville
    2%
  8. 8Riverside
    2%
  9. 9Clovis
    2%
  10. 10Calexico
    2%
  11. 11Compton
    1%
  12. 12Visalia
    1%
  13. 13Turlock
    1%
  14. 14Los Angeles
    1%
  15. 15Anaheim
    1%
  16. 16Stockton
    1%
  17. 17Corcoran
    1%
  18. 18Burbank
    1%
  19. 19Madera
    1%
  20. 20Merced
    1%
  21. 21Glendora
    1%
  22. 22Lake Elsinore
    1%
  23. 23Imperial Beach
    1%
  24. 24Modesto
    1%
  25. 25Yuba City
    1%
  26. 26Huron
    1%
  27. 27Truckee
    0%
  28. 28Redding
    0%
  29. 29Paradise
    0%
  30. 30Red Bluff
    0%
  31. 31Ukiah
    0%
  32. 32Crestline
    0%
  33. 33Carsonlow-cost sensors
    0%
  34. 34Long Beach
    0%
  35. 35Chico
    0%
  36. 36Manteca
    0%
  37. 37Oakland
    0%
  38. 38Woodland
    0%
  39. 39Lancaster
    0%
  40. 40Victorville
    0%
  41. 41San Diego
    0%
  42. 42Hawthornelow-cost sensors
    0%
  43. 43Inglewoodlow-cost sensors
    0%
  44. 43Santa Clarita
    0%
  45. 45Torrancelow-cost sensors
    0%
  46. 46Chula Vista
    0%
  47. 46Rio Vista
    0%
  48. 48La Crescenta-Montroselow-cost sensors
    0%
  49. 49Indio
    0%
  50. 49Santa Monicalow-cost sensors
    0%
  51. 51Agouralow-cost sensors
    0%
  52. 51El Cajon
    0%
  53. 51Lomitalow-cost sensors
    0%
  54. 54San Jose
    0%
  55. 55Brawley
    0%
  56. 56El Centro
    0%
  57. 56Arden-Arcade
    0%
  58. 58Banning
    0%
  59. 58Oceanside
    0%
  60. 60Poway
    0%
  61. 61Sacramento
    0%
  62. 61Santa Barbara
    0%
  63. 61Simi Valley
    0%
  64. 64Hollister
    0%
  65. 65Roseville
    0%
  66. 66Alpine
    0%
  67. 67Thousand Oaks
    0%
  68. 68Ben Lomond
    0%
  69. 68Gridley
    0%
  70. 68San Leandro
    0%
  71. 71San Francisco
    0%
  72. 71Santa Cruz
    0%
  73. 73Colusa
    0%
  74. 73Salinas
    0%
  75. 75Fillmore
    0%
  76. 75Galt
    0%
  77. 75Guadalupe
    0%
  78. 78Oceano
    0%
  79. 78Pleasanton
    0%
  80. 78Redwood City
    0%
  81. 78Yreka
    0%
  82. 82Lincoln
    0%
  83. 83Folsom
    0%
  84. 83King City
    0%
  85. 83Orcutt
    0%
  86. 83Tracy
    0%
  87. 83Willows
    0%
  88. 88Carpinteria
    0%
  89. 88North Auburn
    0%
  90. 90Ojai
    0%
  91. 90San Rafael
    0%
  92. 92Atascadero
    0%
  93. 93Rancho Murieta
    0%
  94. 94Alta Sierra
    0%
  95. 94Davis
    0%
  96. 94Grass Valley
    0%
  97. 97Lompoc
    0%
  98. 98San Luis Obispo
    0%
  99. 98Vacaville
    0%
  100. 100Solvang
    0%

Low-cost sensors: consumer units, counted only in cities with no government-grade monitor; they read close to reference monitors on the whole, but 15 to 25% high in humid air. How we use them.

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

All cities in the world, 2024 · All cities in United States, 2024 · California now

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SmogRank, most polluted cities in California, United States, PM2.5, 2024, smogrank.com/us/region/california/history/2024 (accessed 6 Oct 2026).

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