| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F | |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°F | |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F | |
| Average First Frost Date: | Aug. 21 - Aug. 31 | |
| Average Last Frost Date: | Jul. 1 - Jul. 10 | |
| Koppen-Geiger Climate Zone: | Dsb - Humid Continental Climate - Dry Cool Summer | |
| Ecoregion: | 15k - Clark Fork Valley and Mountains | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 59873 - Thompson Falls, MT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 19 | 22 | 26 | 32 | 38 | 44 | 48 | 48 | 40 | 32 | 27 | 20 | 33 |
| Avg Max Temp (°F) | 33 | 40 | 49 | 59 | 68 | 75 | 84 | 84 | 74 | 59 | 41 | 33 | 58 |
| Avg Precip (In.) | 2.36 | 1.88 | 1.66 | 1.41 | 2.15 | 2.05 | 1.17 | 1.15 | 1.09 | 1.58 | 2.45 | 2.55 | 21.49 |