Trenton, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.6 °C (low) to 17.3 °C (high). Annual precipitation averages 1018.5 Millimeters. Trenton is located in USDA Plant Hardiness Zone 6a. 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 | -8.7 °C | 1.6 °C | 29.97 mm |
| February | -6.5 °C | 4.5 °C | 41.66 mm |
| March | -0.8 °C | 11.2 °C | 61.21 mm |
| April | 5.1 °C | 17.6 °C | 99.31 mm |
| May | 11.4 °C | 23.2 °C | 145.03 mm |
| June | 16.9 °C | 28.6 °C | 130.81 mm |
| July | 19.2 °C | 30.8 °C | 123.44 mm |
| August | 17.8 °C | 29.9 °C | 105.92 mm |
| September | 12.8 °C | 26.1 °C | 103.63 mm |
| October | 6.1 °C | 19 °C | 78.23 mm |
| November | -0.2 °C | 11.2 °C | 56.64 mm |
| December | -5.9 °C | 4.2 °C | 42.67 mm |
| Annual | 5.6 °C | 17.3 °C | 1018.52 mm |
| 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 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |