Rumford, Maine has a Subarctic With Cool Summers And Year Around Rainfall climate (Köppen classification: Dfc). Average annual temperatures range from 1 °C (low) to 12.3 °C (high). Annual precipitation averages 1185.2 Millimeters. Rumford is located in USDA Plant Hardiness Zone 5a. 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 | -12.8 °C | -2.7 °C | 77.47 mm |
| February | -12.3 °C | -1.1 °C | 61.21 mm |
| March | -6.9 °C | 3.8 °C | 80.52 mm |
| April | -0.3 °C | 11.2 °C | 105.66 mm |
| May | 5.7 °C | 18.4 °C | 99.82 mm |
| June | 11.1 °C | 23.3 °C | 128.02 mm |
| July | 14 °C | 26.2 °C | 107.44 mm |
| August | 12.8 °C | 25.4 °C | 103.12 mm |
| September | 8.4 °C | 21.4 °C | 85.09 mm |
| October | 2.7 °C | 14 °C | 132.33 mm |
| November | -2.7 °C | 6.8 °C | 109.22 mm |
| December | -8.3 °C | 0.5 °C | 95.25 mm |
| Annual | 1 °C | 12.3 °C | 1185.15 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfc - Subarctic With Cool Summers And Year Around Rainfall |