Amsterdam, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 30.6 °F (low) to 57.3 °F (high). Annual precipitation averages 14.5 Inches. Amsterdam is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 13.5 °F | 34.2 °F | 0.51 in. |
| February | 15.7 °F | 37.3 °F | 0.53 in. |
| March | 22.6 °F | 46.8 °F | 0.87 in. |
| April | 29.5 °F | 55.2 °F | 1.65 in. |
| May | 37.8 °F | 64.5 °F | 2.33 in. |
| June | 44.7 °F | 73.2 °F | 2.64 in. |
| July | 50.0 °F | 84.4 °F | 1.21 in. |
| August | 47.8 °F | 83.7 °F | 1.03 in. |
| September | 40.5 °F | 73.0 °F | 1.2 in. |
| October | 30.7 °F | 58.1 °F | 1.19 in. |
| November | 20.9 °F | 43.5 °F | 0.74 in. |
| December | 13.3 °F | 33.8 °F | 0.59 in. |
| Annual | 30.6 °F | 57.3 °F | 14.49 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |