Monterey, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40 °F (low) to 59.9 °F (high). Annual precipitation averages 41.5 Inches. Monterey is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 16.2 °F | 31.9 °F | 2.63 in. |
| February | 18.9 °F | 36.2 °F | 2.37 in. |
| March | 27.7 °F | 47.5 °F | 2.63 in. |
| April | 38.1 °F | 59.9 °F | 3.77 in. |
| May | 49.6 °F | 71.1 °F | 4.42 in. |
| June | 59.4 °F | 80.5 °F | 4.59 in. |
| July | 62.2 °F | 83.6 °F | 4.69 in. |
| August | 60.4 °F | 81.7 °F | 4.34 in. |
| September | 52.7 °F | 76.3 °F | 3.43 in. |
| October | 41.4 °F | 63.8 °F | 3.2 in. |
| November | 31.4 °F | 49.0 °F | 3.0 in. |
| December | 22.2 °F | 37.3 °F | 2.39 in. |
| Annual | 40 °F | 59.9 °F | 41.46 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |