Wettest counties in California
Rain, sleet, snow, hail, wintry mix. Precipitation takes on many forms, and the degree to which climate change affects precipitation levels comes down to something almost everyone learns about in school—Earth's water cycle. A system in endless motion, the water cycle traces the process through which water exists in its three primary phases—liquid, solid, and gas—as it moves perpetually between the Earth and its atmosphere.
Increases in precipitation frequency and intensity are markers of climate change. When temperatures rise and oceans grow warmer, the amount of water that evaporates into the atmosphere—and the speed at which it does so—also increases. As atmospheric circulation carries the moisture-rich air over land or pushes it into a storm system, heavy rain or snow is often the result.
The continental U.S. on average received about 30 inches of precipitation between March 2022 and February 2023. Traditionally "wet" regions—such as Washington state and Alaska in the northwest and Georgia and Mississippi in the southeast—continue to have some of the rainiest counties in the United States. Other areas such as Oklahoma, Kansas, and Nebraska, as well as pockets of the South and of California, experience the opposite extreme: drought, also largely a product of climate change.
Stacker cited data from the National Centers for Environmental Information to identify the counties in California that receive the most precipitation through rain, sleet, or snow. Counties are ranked by five-year precipitation averages in inches as of February 2023 with rainfall over the past year serving as a tiebreaker. Supplementary data on how last year's precipitation compares to the 100-year average for the area is also included.
#50. Stanislaus County
- Precipitation over the past year: 19.04 inches (#118 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 5.35 inches above norm
#49. San Joaquin County
- Precipitation over the past year: 19.22 inches (#117 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 5.12 inches above norm
#48. San Diego County
- Precipitation over the past year: 17.06 inches (#98 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 2.74 inches above norm
#47. Los Angeles County
- Precipitation over the past year: 21.32 inches (#106 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 5.72 inches above norm
#46. Mono County
- Precipitation over the past year: 25.12 inches (#123 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 9.44 inches above norm
#45. San Benito County
- Precipitation over the past year: 21.18 inches (#100 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 4.37 inches above norm
#44. Modoc County
- Precipitation over the past year: 17.62 inches (#67 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -0.50 inches below norm
#43. Sutter County
- Precipitation over the past year: 20.29 inches (#81 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 1.27 inches above norm
#42. Contra Costa County
- Precipitation over the past year: 25.37 inches (#114 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 6.83 inches above norm
#41. Alameda County
- Precipitation over the past year: 26.41 inches (#119 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 7.60 inches above norm
#40. San Luis Obispo County
- Precipitation over the past year: 25.42 inches (#119 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 8.20 inches above norm
#39. Sacramento County
- Precipitation over the past year: 22.43 inches (#95 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 3.69 inches above norm
#38. Lassen County
- Precipitation over the past year: 18.81 inches (#56 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -1.66 inches below norm
#37. Solano County
- Precipitation over the past year: 24.36 inches (#101 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 4.52 inches above norm
#36. Santa Barbara County
- Precipitation over the past year: 28.39 inches (#118 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 9.53 inches above norm
#35. Fresno County
- Precipitation over the past year: 28.53 inches (#121 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 8.86 inches above norm
#34. Yolo County
- Precipitation over the past year: 23.79 inches (#96 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 3.73 inches above norm
#33. Colusa County
- Precipitation over the past year: 24.09 inches (#80 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 2.05 inches above norm
#32. Ventura County
- Precipitation over the past year: 29.60 inches (#114 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 9.16 inches above norm
#31. Madera County
- Precipitation over the past year: 28.33 inches (#108 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 5.13 inches above norm
#30. Tulare County
- Precipitation over the past year: 28.80 inches (#112 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 6.87 inches above norm
#29. Monterey County
- Precipitation over the past year: 26.92 inches (#108 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 6.75 inches above norm
#28. Glenn County
- Precipitation over the past year: 26.65 inches (#73 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 0.72 inches above norm
#27. San Francisco County
- Precipitation over the past year: 31.44 inches (#108 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 7.08 inches above norm
#26. Santa Clara County
- Precipitation over the past year: 33.02 inches (#115 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 9.82 inches above norm
#25. San Mateo County
- Precipitation over the past year: 36.63 inches (#108 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 7.88 inches above norm
#24. Napa County
- Precipitation over the past year: 34.04 inches (#87 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 2.87 inches above norm
#23. Mariposa County
- Precipitation over the past year: 41.64 inches (#110 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 8.72 inches above norm
#22. Siskiyou County
- Precipitation over the past year: 33.12 inches (#40 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -5.78 inches below norm
#21. Marin County
- Precipitation over the past year: 38.16 inches (#83 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 2.57 inches above norm
#20. Tehama County
- Precipitation over the past year: 35.18 inches (#64 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -1.43 inches below norm
#19. Santa Cruz County
- Precipitation over the past year: 46.66 inches (#117 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 13.50 inches above norm
#18. Yuba County
- Precipitation over the past year: 38.46 inches (#74 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 0.64 inches above norm
#17. Calaveras County
- Precipitation over the past year: 44.01 inches (#110 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 9.65 inches above norm
#16. Amador County
- Precipitation over the past year: 47.18 inches (#115 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 11.86 inches above norm
#15. Shasta County
- Precipitation over the past year: 38.06 inches (#50 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -3.96 inches below norm
#14. Sonoma County
- Precipitation over the past year: 43.99 inches (#77 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 1.84 inches above norm
#13. Alpine County
- Precipitation over the past year: 53.32 inches (#119 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 17.05 inches above norm
#12. Butte County
- Precipitation over the past year: 42.71 inches (#68 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -1.81 inches below norm
#11. Lake County
- Precipitation over the past year: 46.42 inches (#79 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 2.87 inches above norm
#10. Plumas County
- Precipitation over the past year: 43.48 inches (#79 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 2.10 inches above norm
#9. Tuolumne County
- Precipitation over the past year: 54.20 inches (#113 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 13.21 inches above norm
#8. Mendocino County
- Precipitation over the past year: 53.89 inches (#76 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 2.14 inches above norm
#7. Sierra County
- Precipitation over the past year: 53.02 inches (#94 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 7.10 inches above norm
#6. El Dorado County
- Precipitation over the past year: 58.73 inches (#112 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 13.96 inches above norm
#5. Placer County
- Precipitation over the past year: 56.99 inches (#105 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 11.08 inches above norm
#4. Trinity County
- Precipitation over the past year: 55.48 inches (#61 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -2.14 inches below norm
#3. Nevada County
- Precipitation over the past year: 59.92 inches (#97 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: 9.40 inches above norm
#2. Humboldt County
- Precipitation over the past year: 62.13 inches (#62 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -1.43 inches below norm
#1. Del Norte County
- Precipitation over the past year: 70.23 inches (#42 rainiest year since 1895)
- Precipitation compared to 1901-2000 average: -9.93 inches below norm