West Greenwich, Rhode Island has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.5 °C (low) to 15.1 °C (high). Annual precipitation averages 1278.4 Millimeters. West Greenwich is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.3 °C | 2.1 °C | 100.33 mm |
| February | -6.7 °C | 3.4 °C | 88.14 mm |
| March | -3 °C | 7.7 °C | 124.97 mm |
| April | 2.6 °C | 14.4 °C | 117.6 mm |
| May | 8.2 °C | 20.2 °C | 88.65 mm |
| June | 13.2 °C | 24.9 °C | 101.35 mm |
| July | 16.7 °C | 28.1 °C | 89.41 mm |
| August | 15.9 °C | 26.6 °C | 103.89 mm |
| September | 12 °C | 22.4 °C | 108.97 mm |
| October | 5.9 °C | 16.2 °C | 124.46 mm |
| November | 0.4 °C | 10.3 °C | 106.17 mm |
| December | -4.1 °C | 4.9 °C | 124.46 mm |
| Annual | 4.5 °C | 15.1 °C | 1278.4 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |