Tennessee heat wave risk
Shelby County has the highest heat wave risk in Tennessee, scoring 99.6 out of 100 — rated "Relatively High" by FEMA's National Risk Index. Recorded heat wave events across Tennessee have increased 361% over the past five years compared to the prior five-year period.
| # | County | NRI score | Rating |
NOAA events 2016–2026 |
|---|---|---|---|---|
| 1 | Shelby County | 99.6 | Relatively High | 107 |
| 2 | Davidson County | 95.4 | Relatively Moderate | 6 |
| 3 | Madison County | 91.6 | Relatively Moderate | 77 |
| 4 | Tipton County | 90.3 | Relatively Moderate | 93 |
| 5 | Montgomery County | 84.3 | Relatively Moderate | 5 |
| 6 | Dyer County | 83.8 | Relatively Moderate | 89 |
| 7 | Rutherford County | 83.6 | Relatively Moderate | 5 |
| 8 | Fayette County | 82.6 | Relatively Moderate | 83 |
| 9 | Gibson County | 82.6 | Relatively Moderate | 78 |
| 10 | Carroll County | 82.5 | Relatively Moderate | 68 |
| 11 | Obion County | 81.7 | Relatively Moderate | 87 |
| 12 | Lauderdale County | 80 | Relatively Moderate | 91 |
| 13 | Hamilton County | 75.6 | Relatively Low | 0 |
| 14 | Henry County | 74.5 | Relatively Low | 67 |
| 15 | Sumner County | 74.2 | Relatively Low | 3 |
| 16 | Hardeman County | 73.2 | Relatively Low | 73 |
| 17 | Knox County | 72.6 | Relatively Low | 0 |
| 18 | Williamson County | 72.5 | Relatively Low | 3 |
| 19 | Hardin County | 71.2 | Relatively Low | 70 |
| 20 | Henderson County | 69.9 | Relatively Low | 70 |
| 21 | Haywood County | 69.6 | Relatively Low | 81 |
| 22 | Weakley County | 68.6 | Relatively Low | 73 |
| 23 | McNairy County | 67 | Relatively Low | 72 |
| 24 | Lake County | 65.1 | Relatively Low | 86 |
| 25 | Robertson County | 64.8 | Relatively Low | 4 |
| 26 | Wilson County | 62 | Relatively Low | 4 |
| 27 | Maury County | 60.9 | Relatively Low | 5 |
| 28 | Crockett County | 59.1 | Relatively Low | 83 |
| 29 | Dickson County | 56.6 | Relatively Low | 6 |
| 30 | Lawrence County | 55.7 | Relatively Low | 4 |
| 31 | Chester County | 55.5 | Relatively Low | 72 |
| 32 | Decatur County | 52.9 | Relatively Low | 70 |
| 33 | Benton County | 50.1 | Relatively Low | 67 |
| 34 | Lincoln County | 50 | Relatively Low | 31 |
| 35 | Bedford County | 48 | Relatively Low | 3 |
| 36 | Bradley County | 46.3 | Relatively Low | 0 |
| 37 | Cheatham County | 45.9 | Relatively Low | 5 |
| 38 | Giles County | 45 | Relatively Low | 2 |
| 39 | Humphreys County | 44.4 | Relatively Low | 2 |
| 40 | Hickman County | 43.7 | Relatively Low | 7 |
| 41 | Macon County | 43.5 | Relatively Low | 1 |
| 42 | Blount County | 42.3 | Relatively Low | 0 |
| 43 | Franklin County | 39.8 | Relatively Low | 12 |
| 44 | Stewart County | 39.2 | Relatively Low | 4 |
| 45 | Wayne County | 37.6 | Very Low | 3 |
| 46 | Coffee County | 36.9 | Very Low | 2 |
| 47 | Sevier County | 36.2 | Very Low | 0 |
| 48 | McMinn County | 35.9 | Very Low | 0 |
| 49 | Putnam County | 35.6 | Very Low | 0 |
| 50 | Monroe County | 34.4 | Very Low | 0 |
| 51 | Anderson County | 33.3 | Very Low | 0 |
| 52 | Marshall County | 32.8 | Very Low | 4 |
| 53 | Perry County | 30.5 | Very Low | 0 |
| 54 | Loudon County | 29.9 | Very Low | 0 |
| 55 | Roane County | 29.6 | Very Low | 0 |
| 56 | Rhea County | 28.4 | Very Low | 0 |
| 57 | Marion County | 27.5 | Very Low | 0 |
| 58 | Lewis County | 27.2 | Very Low | 5 |
| 59 | Houston County | 26.9 | Very Low | 1 |
| 60 | Smith County | 25.8 | Very Low | 1 |
| 61 | DeKalb County | 24.4 | Very Low | 1 |
| 62 | Jackson County | 24.2 | Very Low | 0 |
| 63 | Hamblen County | 23 | Very Low | 1 |
| 64 | Jefferson County | 22.1 | Very Low | 0 |
| 65 | Warren County | 20.7 | Very Low | 0 |
| 66 | Cannon County | 20.5 | Very Low | 2 |
| 67 | Trousdale County | 19.7 | Very Low | 0 |
| 68 | Meigs County | 19 | Very Low | 0 |
| 69 | Polk County | 18.7 | Very Low | 0 |
| 70 | Sullivan County | 18.5 | Very Low | 0 |
| 71 | White County | 18.2 | Very Low | 1 |
| 72 | Cocke County | 18.1 | Very Low | 0 |
| 73 | Moore County | 17.3 | Very Low | 11 |
| 74 | Clay County | 17.2 | Very Low | 0 |
| 75 | Washington County | 16.8 | Very Low | 0 |
| 76 | Overton County | 16.7 | Very Low | 0 |
| 77 | Sequatchie County | 16.3 | Very Low | 0 |
| 78 | Bledsoe County | 16.2 | Very Low | 0 |
| 79 | Greene County | 15 | Very Low | 0 |
| 80 | Grainger County | 14.3 | Very Low | 0 |
| 81 | Carter County | 13.7 | Very Low | 0 |
| 82 | Hawkins County | 12.6 | Very Low | 0 |
| 83 | Union County | 11.6 | Very Low | 0 |
| 84 | Claiborne County | 9.8 | Very Low | 0 |
| 85 | Campbell County | 8.5 | Very Low | 0 |
| 86 | Pickett County | 8.3 | Very Low | 0 |
| 87 | Scott County | 6.2 | Very Low | 0 |
| 88 | Grundy County | 5.7 | Very Low | 0 |
| 89 | Fentress County | 5.4 | Very Low | 0 |
| 90 | Morgan County | 4.5 | Very Low | 0 |
| 91 | Hancock County | 4 | Very Low | 0 |
| 92 | Van Buren County | 3.1 | Very Low | 0 |
| 93 | Johnson County | 2 | Very Low | 0 |
| 94 | Unicoi County | 1.8 | Very Low | 0 |
| 95 | Cumberland County | 0 | No Rating | 0 |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Heat Wave risk nationally:
Other hazard risks in Tennessee:
Frequently asked questions
What is the highest heat wave risk county in Tennessee?
Shelby County, TN has the highest heat wave risk in Tennessee, with a FEMA National Risk Index score of 99.6 out of 100 (rated "Relatively High").
What causes heat wave risk in Tennessee?
Heat is consistently the leading cause of weather-related mortality in the US, yet it remains underrepresented in federal disaster declarations relative to its actual impact. High scores reflect a combination of extreme temperature exposure, population vulnerability (elderly, outdoor workers), and limited access to cooling infrastructure.