Martin City, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.4 °C (low) to 12.5 °C (high). Annual precipitation averages 682.2 Millimeters. 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 | -8.4 °C | -0.5 °C | 59.44 mm |
| February | -8.1 °C | 1.9 °C | 45.97 mm |
| March | -4.7 °C | 6.7 °C | 47.24 mm |
| April | -1.2 °C | 11.9 °C | 50.55 mm |
| May | 3.1 °C | 17.8 °C | 64.01 mm |
| June | 6.6 °C | 21.4 °C | 89.66 mm |
| July | 8.8 °C | 27.5 °C | 34.29 mm |
| August | 7.8 °C | 27.3 °C | 29.72 mm |
| September | 3.9 °C | 20.9 °C | 46.99 mm |
| October | -0.7 °C | 12 °C | 71.88 mm |
| November | -4.2 °C | 3.9 °C | 71.37 mm |
| December | -7.3 °C | -0.7 °C | 71.12 mm |
| Annual | -0.4 °C | 12.5 °C | 682.24 mm |
| 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 : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |