Iraan, Texas has a Hot Semi-Arid Climate climate (Köppen classification: BSh). Average annual temperatures range from 11.4 °C (low) to 26.7 °C (high). Annual precipitation averages 381.5 Millimeters. Iraan is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.1 °C | 16.1 °C | 19.3 mm |
| February | 2.2 °C | 18.8 °C | 17.53 mm |
| March | 6.7 °C | 23 °C | 21.59 mm |
| April | 10.8 °C | 27.8 °C | 21.59 mm |
| May | 16.7 °C | 31.8 °C | 46.23 mm |
| June | 20.9 °C | 34.7 °C | 42.67 mm |
| July | 22.3 °C | 35.8 °C | 34.54 mm |
| August | 21.7 °C | 35.4 °C | 47.24 mm |
| September | 18.2 °C | 32 °C | 52.07 mm |
| October | 11.8 °C | 27.2 °C | 40.39 mm |
| November | 5.1 °C | 20.7 °C | 22.1 mm |
| December | 0.8 °C | 16.5 °C | 16.26 mm |
| Annual | 11.4 °C | 26.7 °C | 381.51 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BSh - Hot Semi-Arid Climate |