Heat Wave Risk in Montana
All Montana counties ranked by FEMA National Risk Index heat wave score
Heat Wave risk — prolonged periods of extreme heat that threaten health and infrastructure — is rated for 56 of 56 Montana counties in FEMA's National Risk Index. Yellowstone County carries the state's highest heat wave score at 72.3, with $1M in expected annual heat wave losses.
No Montana county reaches the High band for heat wave, and expected annual losses from heat wave total roughly $7M statewide. The full ranking below links to each county's complete 18-hazard risk profile.
County Rankings — Heat Wave
| # | County | Heat Wave Score | Rating | Ann. Freq. | Ann. Loss |
|---|---|---|---|---|---|
| 1 | Yellowstone County | Low | 2.21 / yr | $1M | |
| 2 | Dawson County | Low | 2.68 / yr | $594K | |
| 3 | Flathead County | Low | 1.30 / yr | $632K | |
| 4 | Missoula County | Low | 1.16 / yr | $675K | |
| 5 | Roosevelt County | Low | 2.48 / yr | $191K | |
| 6 | Ravalli County | Low | 0.74 / yr | $307K | |
| 7 | Richland County | Low | 2.53 / yr | $413K | |
| 8 | Cascade County | Low | 1.15 / yr | $335K | |
| 9 | Lake County | Very Low | 1.44 / yr | $184K | |
| 10 | Custer County | Very Low | 2.21 / yr | $162K | |
| 11 | Lincoln County | Very Low | 2.09 / yr | $131K | |
| 12 | Lewis and Clark County | Very Low | 0.70 / yr | $213K | |
| 13 | Big Horn County | Very Low | 2.02 / yr | $103K | |
| 14 | Rosebud County | Very Low | 2.26 / yr | $82K | |
| 15 | Sanders County | Very Low | 2.07 / yr | $86K | |
| 16 | Gallatin County | Very Low | 0.29 / yr | $186K | |
| 17 | Valley County | Very Low | 2.42 / yr | $98K | |
| 18 | Hill County | Very Low | 1.32 / yr | $76K | |
| 19 | Carbon County | Very Low | 1.07 / yr | $52K | |
| 20 | Blaine County | Very Low | 1.47 / yr | $38K | |
| 21 | Phillips County | Very Low | 2.51 / yr | $46K | |
| 22 | Fergus County | Very Low | 1.43 / yr | $61K | |
| 23 | Prairie County | Very Low | 2.95 / yr | $40K | |
| 24 | McCone County | Very Low | 2.74 / yr | $56K | |
| 25 | Park County | Very Low | 0.32 / yr | $52K | |
| 26 | Musselshell County | Very Low | 2.11 / yr | $36K | |
| 27 | Sheridan County | Very Low | 1.89 / yr | $37K | |
| 28 | Glacier County | Very Low | 0.51 / yr | $26K | |
| 29 | Chouteau County | Very Low | 1.37 / yr | $35K | |
| 30 | Mineral County | Very Low | 2.16 / yr | $32K | |
| 31 | Stillwater County | Very Low | 1.19 / yr | $45K | |
| 32 | Silver Bow County | Very Low | 0.26 / yr | $38K | |
| 33 | Pondera County | Very Low | 0.74 / yr | $19K | |
| 34 | Fallon County | Very Low | 1.95 / yr | $39K | |
| 35 | Wibaux County | Very Low | 2.58 / yr | $31K | |
| 36 | Toole County | Very Low | 0.95 / yr | $18K | |
| 37 | Garfield County | Very Low | 3.00 / yr | $23K | |
| 38 | Jefferson County | Very Low | 0.45 / yr | $21K | |
| 39 | Powder River County | Very Low | 2.26 / yr | $20K | |
| 40 | Teton County | Very Low | 0.66 / yr | $18K | |
| 41 | Broadwater County | Very Low | 0.48 / yr | $13K | |
| 42 | Liberty County | Very Low | 1.16 / yr | $11K | |
| 43 | Daniels County | Very Low | 1.74 / yr | $17K | |
| 44 | Carter County | Very Low | 1.84 / yr | $16K | |
| 45 | Deer Lodge County | Very Low | 0.26 / yr | $10K | |
| 46 | Judith Basin County | Very Low | 1.11 / yr | $12K | |
| 47 | Wheatland County | Very Low | 0.98 / yr | $8K | |
| 48 | Sweet Grass County | Very Low | 0.75 / yr | $13K | |
| 49 | Treasure County | Very Low | 2.26 / yr | $10K | |
| 50 | Powell County | Very Low | 0.39 / yr | $6K | |
| 51 | Madison County | Very Low | 0.16 / yr | $8K | |
| 52 | Petroleum County | Very Low | 2.90 / yr | $7K | |
| 53 | Beaverhead County | Very Low | 0.05 / yr | $4K | |
| 54 | Golden Valley County | Very Low | 1.35 / yr | $5K | |
| 55 | Granite County | Very Low | 0.38 / yr | $4K | |
| 56 | Meagher County | Very Low | 0.42 / yr | $3K |
56 Montana counties with measurable heat wave risk. See the national heat wave ranking or all Montana counties by overall risk.
Frequently Asked Questions
Which Montana county has the highest heat wave risk?
Yellowstone County has the highest FEMA heat wave risk score in Montana at 72.3 (Low), with $1M in expected annual losses and about 2.21 events per year.
How many Montana counties face significant heat wave risk?
56 Montana counties record measurable heat wave risk in FEMA's National Risk Index; 0 of them are rated High or Very High.