Billings, Montana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.4 °C (low) to 16.6 °C (high). Annual precipitation averages 378.2 Millimeters. Billings is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.7 °C | 3.2 °C | 13.21 mm |
| February | -8.4 °C | 5.4 °C | 13.21 mm |
| March | -4 °C | 11.1 °C | 24.38 mm |
| April | 0.8 °C | 15.5 °C | 47.24 mm |
| May | 5.8 °C | 20.7 °C | 59.94 mm |
| June | 10.5 °C | 26.2 °C | 59.69 mm |
| July | 13.8 °C | 31.6 °C | 33.27 mm |
| August | 12.4 °C | 30.9 °C | 21.34 mm |
| September | 7.4 °C | 25 °C | 37.85 mm |
| October | 1.2 °C | 16.7 °C | 38.35 mm |
| November | -4.6 °C | 9.2 °C | 14.99 mm |
| December | -8.9 °C | 3.6 °C | 14.73 mm |
| Annual | 1.4 °C | 16.6 °C | 378.2 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 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 |