Marathon, Texas has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 47.5 °F (low) to 78.4 °F (high). Annual precipitation averages 12.8 Inches. Marathon is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 30.1 °F | 61.2 °F | 0.51 in. |
| February | 32.6 °F | 65.8 °F | 0.31 in. |
| March | 39.8 °F | 73.4 °F | 0.36 in. |
| April | 46.7 °F | 81.1 °F | 0.54 in. |
| May | 55.0 °F | 87.4 °F | 0.83 in. |
| June | 62.9 °F | 92.5 °F | 1.89 in. |
| July | 64.4 °F | 91.5 °F | 2.81 in. |
| August | 63.8 °F | 91.4 °F | 1.98 in. |
| September | 58.6 °F | 85.7 °F | 1.77 in. |
| October | 48.5 °F | 79.4 °F | 1.09 in. |
| November | 36.8 °F | 69.5 °F | 0.39 in. |
| December | 30.5 °F | 62.2 °F | 0.33 in. |
| Annual | 47.5 °F | 78.4 °F | 12.81 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |