Martin City, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31.3 °F (low) to 54.5 °F (high). Annual precipitation averages 26.9 Inches. Martin City is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 16.9 °F | 31.1 °F | 2.34 in. |
| February | 17.5 °F | 35.4 °F | 1.81 in. |
| March | 23.5 °F | 44.1 °F | 1.86 in. |
| April | 29.8 °F | 53.5 °F | 1.99 in. |
| May | 37.5 °F | 64.1 °F | 2.52 in. |
| June | 43.8 °F | 70.6 °F | 3.53 in. |
| July | 47.9 °F | 81.5 °F | 1.35 in. |
| August | 46.1 °F | 81.1 °F | 1.17 in. |
| September | 39.0 °F | 69.6 °F | 1.85 in. |
| October | 30.7 °F | 53.6 °F | 2.83 in. |
| November | 24.5 °F | 39.1 °F | 2.81 in. |
| December | 18.8 °F | 30.8 °F | 2.8 in. |
| Annual | 31.3 °F | 54.5 °F | 26.86 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |