| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°F Zone 4a: -30°F to -25°F |
| 2012 Hardiness Zone: | Zone 4b: -25°F to -20°F Zone 4a: -30°F to -25°F |
| 1990 Hardiness Zone: | Zone 3b: -35F to -30F |
| Average First Frost Date: | Aug. 1 - Aug. 10 |
| Average Last Frost Date: | Jul. 1 - Jul. 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 17q - Big Snowy-Little Belt Carbonate Mountains |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 59463 - Monarch, MT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 12 | 16 | 21 | 27 | 35 | 42 | 46 | 46 | 38 | 31 | 21 | 14 | 29 |
| Avg Max Temp (°F) | 34 | 38 | 44 | 52 | 61 | 70 | 78 | 78 | 68 | 57 | 41 | 35 | 55 |
| Avg Precip (In.) | .92 | .65 | 1.28 | 1.74 | 3.38 | 3.14 | 2.24 | 2.04 | 1.95 | 1.35 | .95 | .97 | 20.61 |