Bertrand, Missouri has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9 °C (low) to 20.3 °C (high). Annual precipitation averages 1274.6 Millimeters. Bertrand 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 | 6.3 °C | 94.49 mm |
| February | -1.2 °C | 9.1 °C | 100.33 mm |
| March | 3.3 °C | 14.6 °C | 118.36 mm |
| April | 8.7 °C | 20.8 °C | 134.11 mm |
| May | 14.6 °C | 25.9 °C | 139.45 mm |
| June | 19.1 °C | 30.6 °C | 100.33 mm |
| July | 21 °C | 32.1 °C | 108.97 mm |
| August | 19.7 °C | 31.6 °C | 71.88 mm |
| September | 15.1 °C | 28.3 °C | 82.3 mm |
| October | 8.5 °C | 22.1 °C | 99.82 mm |
| November | 3 °C | 14.3 °C | 109.98 mm |
| December | -1 °C | 8.2 °C | 114.55 mm |
| Annual | 9 °C | 20.3 °C | 1274.57 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 | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |