Amsterdam, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.8 °C (low) to 14.1 °C (high). Annual precipitation averages 368.1 Millimeters. 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 | -10.3 °C | 1.2 °C | 12.95 mm |
| February | -9.1 °C | 2.9 °C | 13.46 mm |
| March | -5.2 °C | 8.2 °C | 22.1 mm |
| April | -1.4 °C | 12.9 °C | 41.91 mm |
| May | 3.2 °C | 18.1 °C | 59.18 mm |
| June | 7.1 °C | 22.9 °C | 67.06 mm |
| July | 10 °C | 29.1 °C | 30.73 mm |
| August | 8.8 °C | 28.7 °C | 26.16 mm |
| September | 4.7 °C | 22.8 °C | 30.48 mm |
| October | -0.7 °C | 14.5 °C | 30.23 mm |
| November | -6.2 °C | 6.4 °C | 18.8 mm |
| December | -10.4 °C | 1 °C | 14.99 mm |
| Annual | -0.8 °C | 14.1 °C | 368.05 mm |
| 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 : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |