Pacific Junction, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.7 °F (low) to 62.1 °F (high). Annual precipitation averages 33.2 Inches. Pacific Junction is located in USDA Plant Hardiness Zone 5b. 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 | 12.6 °F | 32.6 °F | 0.75 in. |
| February | 16.5 °F | 38.0 °F | 0.97 in. |
| March | 27.8 °F | 51.2 °F | 1.79 in. |
| April | 38.6 °F | 63.4 °F | 3.56 in. |
| May | 50.9 °F | 73.6 °F | 5.4 in. |
| June | 61.7 °F | 83.3 °F | 5.24 in. |
| July | 65.8 °F | 86.4 °F | 3.78 in. |
| August | 63.0 °F | 85.2 °F | 3.67 in. |
| September | 53.3 °F | 78.6 °F | 3.01 in. |
| October | 40.5 °F | 66.0 °F | 2.48 in. |
| November | 27.7 °F | 50.0 °F | 1.48 in. |
| December | 17.9 °F | 37.4 °F | 1.08 in. |
| Annual | 39.7 °F | 62.1 °F | 33.21 in. |
| 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 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |