Norman, Oklahoma has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9.7 °C (low) to 22.3 °C (high). Annual precipitation averages 923 Millimeters. Norman is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -2.7 °C | 10.1 °C | 34.29 mm |
| February | -0.6 °C | 12.4 °C | 40.13 mm |
| March | 4.2 °C | 17.4 °C | 68.58 mm |
| April | 8.9 °C | 22.1 °C | 90.93 mm |
| May | 14.7 °C | 26.2 °C | 133.1 mm |
| June | 19.6 °C | 30.9 °C | 110.49 mm |
| July | 21.9 °C | 34.1 °C | 91.44 mm |
| August | 21.1 °C | 33.8 °C | 80.52 mm |
| September | 16.7 °C | 29.4 °C | 86.36 mm |
| October | 10.1 °C | 23.3 °C | 83.06 mm |
| November | 3.8 °C | 16.6 °C | 53.85 mm |
| December | -1.2 °C | 10.9 °C | 50.29 mm |
| Annual | 9.7 °C | 22.3 °C | 923.04 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°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 |