Palmer, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.4 °C (low) to 19.2 °C (high). Annual precipitation averages 1671.1 Millimeters. Palmer is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.2 °C | 7.5 °C | 140.72 mm |
| February | -1.5 °C | 9.7 °C | 146.05 mm |
| March | 2.2 °C | 14.4 °C | 160.27 mm |
| April | 6.7 °C | 19.7 °C | 160.27 mm |
| May | 11.7 °C | 23.7 °C | 134.87 mm |
| June | 15.8 °C | 27.3 °C | 144.53 mm |
| July | 17.7 °C | 29 °C | 153.92 mm |
| August | 17.1 °C | 28.8 °C | 118.62 mm |
| September | 13.7 °C | 26.2 °C | 116.33 mm |
| October | 7.5 °C | 20.5 °C | 96.27 mm |
| November | 2.1 °C | 14.3 °C | 123.44 mm |
| December | -1.2 °C | 9.1 °C | 175.77 mm |
| Annual | 7.4 °C | 19.2 °C | 1671.06 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |