Norco, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 16.5 °C (low) to 25.6 °C (high). Annual precipitation averages 1668.8 Millimeters. Norco is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.2 °C | 16.8 °C | 142.49 mm |
| February | 9.1 °C | 18.9 °C | 112.01 mm |
| March | 12.4 °C | 22.3 °C | 115.82 mm |
| April | 16 °C | 25.6 °C | 127.51 mm |
| May | 20.3 °C | 29.2 °C | 145.8 mm |
| June | 23.4 °C | 31.8 °C | 191.26 mm |
| July | 24.4 °C | 32.7 °C | 187.96 mm |
| August | 24.3 °C | 32.9 °C | 175.26 mm |
| September | 22.6 °C | 30.9 °C | 137.67 mm |
| October | 17.4 °C | 26.7 °C | 102.62 mm |
| November | 11.8 °C | 21.5 °C | 103.89 mm |
| December | 8.6 °C | 18.1 °C | 126.49 mm |
| Annual | 16.5 °C | 25.6 °C | 1668.78 mm |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |