| 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 3b: -35°F to -30°F Zone 4b: -25°F to -20°F Zone 4a: -30°F to -25°F | |
| 1990 Hardiness Zone: | Zone 4a: -30F to -25F | |
| Average First Frost Date: | Sep. 21 - Sep. 30 | |
| Average Last Frost Date: | May 11 - May 20 | |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate | |
| Ecoregion: | 42o - North Central Brown Glaciated Plains | |
| Current Drought Status: | Moderate Drought | |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 59446 - Geraldine, MT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 11 | 16 | 24 | 32 | 41 | 49 | 53 | 52 | 43 | 34 | 22 | 14 | 33 |
| Avg Max Temp (°F) | 34 | 40 | 48 | 59 | 68 | 77 | 85 | 85 | 73 | 61 | 45 | 36 | 59 |
| Avg Precip (In.) | .73 | .47 | .98 | 1.34 | 2.72 | 2.49 | 1.83 | 1.64 | 1.38 | .87 | .63 | .67 | 15.75 |