Ulmer, South Carolina has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.9 °C (low) to 24.7 °C (high). Annual precipitation averages 1235 Millimeters. Ulmer is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.1 °C | 15 °C | 100.58 mm |
| February | 3.4 °C | 16.9 °C | 93.22 mm |
| March | 6.7 °C | 20.8 °C | 99.82 mm |
| April | 10.9 °C | 25.1 °C | 78.23 mm |
| May | 15.8 °C | 28.9 °C | 86.36 mm |
| June | 20 °C | 31.9 °C | 138.18 mm |
| July | 21.9 °C | 33.4 °C | 138.94 mm |
| August | 21.5 °C | 32.3 °C | 143.51 mm |
| September | 18.6 °C | 29.8 °C | 107.7 mm |
| October | 12.3 °C | 25.4 °C | 80.52 mm |
| November | 6.3 °C | 20.2 °C | 72.14 mm |
| December | 3.3 °C | 16.2 °C | 95.76 mm |
| Annual | 11.9 °C | 24.7 °C | 1234.96 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |