Post Falls, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 2.8 °C (low) to 14.7 °C (high). Annual precipitation averages 570 Millimeters. Post Falls 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 | -4 °C | 2.2 °C | 67.31 mm |
| February | -3.9 °C | 4.6 °C | 43.43 mm |
| March | -1.6 °C | 9.3 °C | 58.67 mm |
| April | 1.3 °C | 13.8 °C | 42.67 mm |
| May | 5.6 °C | 19.3 °C | 53.85 mm |
| June | 8.8 °C | 22.7 °C | 49.28 mm |
| July | 11.6 °C | 28.7 °C | 13.46 mm |
| August | 11.3 °C | 28.9 °C | 21.84 mm |
| September | 7.1 °C | 23.3 °C | 20.32 mm |
| October | 2.3 °C | 14.8 °C | 44.96 mm |
| November | -1.2 °C | 6.6 °C | 78.49 mm |
| December | -4.1 °C | 1.8 °C | 75.69 mm |
| Annual | 2.8 °C | 14.7 °C | 569.97 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |