Optima, Oklahoma has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 41.6 °F (low) to 70.8 °F (high). Annual precipitation averages 18.1 Inches. Optima is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 20.1 °F | 48.4 °F | 0.42 in. |
| February | 22.5 °F | 51.8 °F | 0.37 in. |
| March | 30.4 °F | 61.1 °F | 1.15 in. |
| April | 38.9 °F | 69.5 °F | 1.38 in. |
| May | 49.9 °F | 79.2 °F | 2.18 in. |
| June | 60.7 °F | 89.5 °F | 2.61 in. |
| July | 65.4 °F | 93.9 °F | 2.78 in. |
| August | 63.6 °F | 91.7 °F | 2.88 in. |
| September | 55.4 °F | 84.6 °F | 1.3 in. |
| October | 41.8 °F | 72.1 °F | 1.7 in. |
| November | 29.6 °F | 59.5 °F | 0.58 in. |
| December | 21.1 °F | 48.3 °F | 0.72 in. |
| Annual | 41.6 °F | 70.8 °F | 18.07 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |