Ames Lake, Washington has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.5 °C (low) to 15.7 °C (high). Annual precipitation averages 1195.8 Millimeters. Ames Lake is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.9 °C | 8.1 °C | 157.23 mm |
| February | 1.9 °C | 9.6 °C | 116.08 mm |
| March | 3.2 °C | 11.8 °C | 124.97 mm |
| April | 5 °C | 14.7 °C | 98.55 mm |
| May | 8.1 °C | 18.6 °C | 71.63 mm |
| June | 10.4 °C | 20.8 °C | 66.8 mm |
| July | 12.5 °C | 24.6 °C | 24.13 mm |
| August | 12.6 °C | 25.1 °C | 30.73 mm |
| September | 10.4 °C | 21.7 °C | 52.83 mm |
| October | 6.9 °C | 15.6 °C | 124.46 mm |
| November | 3.9 °C | 10.6 °C | 175.51 mm |
| December | 1.7 °C | 7.4 °C | 152.91 mm |
| Annual | 6.5 °C | 15.7 °C | 1195.83 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |