Norway, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38.6 °F (low) to 58.8 °F (high). Annual precipitation averages 37.1 Inches. Norway is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 11.6 °F | 28.3 °F | 1.1 in. |
| February | 15.3 °F | 32.9 °F | 1.27 in. |
| March | 26.5 °F | 46.1 °F | 2.11 in. |
| April | 37.6 °F | 60.3 °F | 3.7 in. |
| May | 49.7 °F | 71.3 °F | 4.6 in. |
| June | 60.2 °F | 80.7 °F | 5.42 in. |
| July | 63.5 °F | 83.8 °F | 4.37 in. |
| August | 60.8 °F | 82.0 °F | 4.33 in. |
| September | 52.2 °F | 75.9 °F | 3.62 in. |
| October | 40.2 °F | 62.8 °F | 2.87 in. |
| November | 28.1 °F | 47.1 °F | 2.15 in. |
| December | 17.8 °F | 33.9 °F | 1.58 in. |
| Annual | 38.6 °F | 58.8 °F | 37.12 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°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 |