How much have temperatures changed across the U.S.? I live on the East Coast, where the hotter temperatures have been noticeable for the past few weeks. The East Coast isn’t alone when it comes to experiencing heat waves. If you look at graphics for the highest deviation from July norms, the U.S. is framed in red.
Check out NOAA’s global temperature history as the difference is alarming. The global temperature keeps increasing by about 0.11ºF per decade. That may not seem like a lot, but it’s speeding up. If you look at how fast the temperature has increased since the early 1980s, it’s going up at about 0.36ºF per decade. It’s becoming noticeable.
When I was younger and lived in California, I don’t remember experiencing extreme heat. Sure, it was sunny and warm with mild winters, but my parents never relied on AC to keep us cool. Now on the other side of the country, I cannot imagine not getting my window ACs set up in the bedrooms and living room. It’s getting earlier each year, too. I used to not need them until June, but this year, we needed them by early May. It gets earlier each year.
I’m not alone. Global air conditioner sales increased by 5% over 2022. The residential market grew by over 9%. It’s expected sales in 2024 will top $63.2 billion. The hotter it gets outside, the faster AC sales increase.
In the past few years, heat-related deaths have increased to as many as 2,302 in 2023. That was about 600 more deaths than in 2022. Heat waves are not to be taken lightly, no matter what county you’re in. (Read “The Highest Temperature Ever Recorded on Earth” to see the record high.)
Methodology:
To determine the counties experiencing the worst heat waves right now, 24/7 Tempo reviewed data on daily average temperature from the NOAA’s nClimGrid-Daily program. Counties were ranked based on the raw differential in average daily temperature from the period July 1-6, 1981-2010 to July-16, 2024. Supplemental data on population is from the U.S. Census Bureau’s 2022 American Community Survey.
50. Kings County, CA
- Avg. temperature, July 1-6, 2024: 88.0°F (+8.1°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 79.9°F
- Total population: 152,515
- County seat: Hanford
49. Jackson County, OR
- Avg. temperature, July 1-6, 2024: 72.6°F (+8.1°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 64.4°F
- Total population: 222,604
- County seat: Medford
48. Ventura County, CA
- Avg. temperature, July 1-6, 2024: 77.1°F (+8.2°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 68.9°F
- Total population: 842,009
- County seat: Ventura
47. Douglas County, OR
- Avg. temperature, July 1-6, 2024: 70.9°F (+8.4°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 62.6°F
- Total population: 111,322
- County seat: Roseburg
46. San Luis Obispo County, CA
- Avg. temperature, July 1-6, 2024: 79.5°F (+8.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 71.0°F
- Total population: 281,712
- County seat: San Luis Obispo
45. Tulare County, CA
- Avg. temperature, July 1-6, 2024: 79.9°F (+8.7°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 71.2°F
- Total population: 473,446
- County seat: Visalia
44. Coos County, OR
- Avg. temperature, July 1-6, 2024: 70.0°F (+9.0°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 61.1°F
- Total population: 64,908
- County seat: Coquille
43. Fresno County, CA
- Avg. temperature, July 1-6, 2024: 80.8°F (+9.0°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 71.7°F
- Total population: 1,008,280
- County seat: Fresno
42. Siskiyou County, CA
- Avg. temperature, July 1-6, 2024: 73.1°F (+9.1°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 64.0°F
- Total population: 44,049
- County seat: Yreka
41. Tuolumne County, CA
- Avg. temperature, July 1-6, 2024: 74.8°F (+9.2°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 65.6°F
- Total population: 54,993
- County seat: Sonora
40. San Francisco County, CA
- Avg. temperature, July 1-6, 2024: 71.4°F (+9.4°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 62.0°F
- Total population: 851,036
- County seat: San Francisco
39. El Dorado County, CA
- Avg. temperature, July 1-6, 2024: 78.7°F (+9.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 69.1°F
- Total population: 191,713
- County seat: Placerville
38. Madera County, CA
- Avg. temperature, July 1-6, 2024: 81.9°F (+9.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 72.3°F
- Total population: 157,243
- County seat: Madera
37. Sierra County, CA
- Avg. temperature, July 1-6, 2024: 72.5°F (+9.9°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 62.6°F
- Total population: 2,916
- County seat: Downieville
36. Merced County, CA
- Avg. temperature, July 1-6, 2024: 87.1°F (+10.0°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 77.1°F
- Total population: 282,290
- County seat: Merced
35. Placer County, CA
- Avg. temperature, July 1-6, 2024: 78.9°F (+10.0°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 68.8°F
- Total population: 406,608
- County seat: Auburn
34. Plumas County, CA
- Avg. temperature, July 1-6, 2024: 74.0°F (+10.4°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 63.6°F
- Total population: 19,650
- County seat: Quincy
33. Sutter County, CA
- Avg. temperature, July 1-6, 2024: 88.5°F (+10.4°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 78.1°F
- Total population: 99,101
- County seat: Yuba City
32. Curry County, OR
- Avg. temperature, July 1-6, 2024: 72.9°F (+10.5°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 62.4°F
- Total population: 23,404
- County seat: Gold Beach
31. Mariposa County, CA
- Avg. temperature, July 1-6, 2024: 81.8°F (+10.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 71.3°F
- Total population: 17,130
- County seat: Mariposa
30. Shasta County, CA
- Avg. temperature, July 1-6, 2024: 81.9°F (+10.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 71.3°F
- Total population: 181,852
- County seat: Redding
29. Trinity County, CA
- Avg. temperature, July 1-6, 2024: 77.7°F (+10.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 67.1°F
- Total population: 15,889
- County seat: Weaverville
28. Santa Cruz County, CA
- Avg. temperature, July 1-6, 2024: 74.8°F (+10.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 64.2°F
- Total population: 268,571
- County seat: Santa Cruz
27. Josephine County, OR
- Avg. temperature, July 1-6, 2024: 74.3°F (+10.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 63.6°F
- Total population: 87,994
- County seat: Grants Pass
26. Nevada County, CA
- Avg. temperature, July 1-6, 2024: 78.2°F (+10.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 67.5°F
- Total population: 102,322
- County seat: Nevada City
25. Yuba County, CA
- Avg. temperature, July 1-6, 2024: 87.0°F (+10.8°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 76.1°F
- Total population: 81,705
- County seat: Marysville
24. Amador County, CA
- Avg. temperature, July 1-6, 2024: 83.7°F (+10.8°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 72.8°F
- Total population: 40,577
- County seat: Jackson
23. San Mateo County, CA
- Avg. temperature, July 1-6, 2024: 73.9°F (+10.9°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 63.0°F
- Total population: 754,250
- County seat: Redwood City
22. Tehama County, CA
- Avg. temperature, July 1-6, 2024: 85.7°F (+10.9°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 74.8°F
- Total population: 65,484
- County seat: Red Bluff
21. Colusa County, CA
- Avg. temperature, July 1-6, 2024: 87.7°F (+10.9°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 76.8°F
- Total population: 21,811
- County seat: Colusa
20. Alameda County, CA
- Avg. temperature, July 1-6, 2024: 80.8°F (+11.0°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 69.8°F
- Total population: 1,663,823
- County seat: Oakland
19. Yolo County, CA
- Avg. temperature, July 1-6, 2024: 87.5°F (+11.1°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 76.5°F
- Total population: 217,141
- County seat: Woodland
18. Stanislaus County, CA
- Avg. temperature, July 1-6, 2024: 87.1°F (+11.1°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 76.0°F
- Total population: 552,063
- County seat: Modesto
17. Monterey County, CA
- Avg. temperature, July 1-6, 2024: 80.0°F (+11.1°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 68.9°F
- Total population: 437,609
- County seat: Salinas
16. Glenn County, CA
- Avg. temperature, July 1-6, 2024: 87.1°F (+11.3°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 75.8°F
- Total population: 28,657
- County seat: Willows
15. Del Norte County, CA
- Avg. temperature, July 1-6, 2024: 74.4°F (+11.4°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 63.0°F
- Total population: 27,462
- County seat: Crescent City
14. San Benito County, CA
- Avg. temperature, July 1-6, 2024: 83.7°F (+11.5°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 72.3°F
- Total population: 64,753
- County seat: Hollister
13. Humboldt County, CA
- Avg. temperature, July 1-6, 2024: 75.8°F (+11.5°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 64.3°F
- Total population: 136,132
- County seat: Eureka
12. San Joaquin County, CA
- Avg. temperature, July 1-6, 2024: 87.3°F (+11.6°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 75.7°F
- Total population: 779,445
- County seat: Stockton
11. Butte County, CA
- Avg. temperature, July 1-6, 2024: 86.9°F (+11.7°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 75.3°F
- Total population: 213,605
- County seat: Oroville
10. Solano County, CA
- Avg. temperature, July 1-6, 2024: 85.0°F (+11.7°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 73.2°F
- Total population: 450,995
- County seat: Fairfield
9. Sacramento County, CA
- Avg. temperature, July 1-6, 2024: 87.7°F (+11.7°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 76.0°F
- Total population: 1,579,211
- County seat: Sacramento
8. Calaveras County, CA
- Avg. temperature, July 1-6, 2024: 85.3°F (+11.8°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 73.4°F
- Total population: 45,674
- County seat: San Andreas
7. Santa Clara County, CA
- Avg. temperature, July 1-6, 2024: 81.5°F (+11.9°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 69.5°F
- Total population: 1,916,831
- County seat: San Jose
6. Contra Costa County, CA
- Avg. temperature, July 1-6, 2024: 83.6°F (+12.3°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 71.4°F
- Total population: 1,162,648
- County seat: Martinez
5. Mendocino County, CA
- Avg. temperature, July 1-6, 2024: 78.9°F (+12.4°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 66.5°F
- Total population: 91,145
- County seat: Ukiah
4. Lake County, CA
- Avg. temperature, July 1-6, 2024: 84.2°F (+12.5°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 71.8°F
- Total population: 68,024
- County seat: Lakeport
3. Marin County, CA
- Avg. temperature, July 1-6, 2024: 74.6°F (+13.0°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 61.6°F
- Total population: 260,485
- County seat: San Rafael
2. Napa County, CA
- Avg. temperature, July 1-6, 2024: 85.4°F (+13.4°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 72.0°F
- Total population: 137,384
- County seat: Napa
1. Sonoma County, CA
- Avg. temperature, July 1-6, 2024: 80.0°F (+14.1°F hotter than normal)
- Avg. temperature, July 1-6, 1981-2010: 66.0°F
- Total population: 488,436
- County seat: Santa Rosa