Mexico, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.5 °C (low) to 17.9 °C (high). Annual precipitation averages 1082.8 Millimeters. Mexico is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7 °C | 2.9 °C | 55.88 mm |
| February | -5.2 °C | 5.6 °C | 59.44 mm |
| March | 0.1 °C | 11.9 °C | 74.68 mm |
| April | 6.1 °C | 18.3 °C | 112.78 mm |
| May | 12.1 °C | 23.5 °C | 134.62 mm |
| June | 17.2 °C | 28.4 °C | 125.98 mm |
| July | 19.3 °C | 30.5 °C | 108.46 mm |
| August | 18.3 °C | 30.3 °C | 93.47 mm |
| September | 13.4 °C | 26.3 °C | 106.43 mm |
| October | 6.9 °C | 19.6 °C | 81.79 mm |
| November | 1.1 °C | 12.1 °C | 72.14 mm |
| December | -4.1 °C | 5.3 °C | 57.15 mm |
| Annual | 6.5 °C | 17.9 °C | 1082.82 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |