Brookside, Delaware has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 45.1 °F (low) to 64.4 °F (high). Annual precipitation averages 47.7 Inches. Brookside is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 24.4 °F | 41.0 °F | 3.44 in. |
| February | 25.2 °F | 43.5 °F | 2.89 in. |
| March | 32.3 °F | 51.7 °F | 4.3 in. |
| April | 42.8 °F | 63.8 °F | 3.64 in. |
| May | 52.5 °F | 73.3 °F | 3.82 in. |
| June | 61.7 °F | 82.2 °F | 4.73 in. |
| July | 66.9 °F | 86.6 °F | 4.73 in. |
| August | 65.4 °F | 84.7 °F | 4.22 in. |
| September | 58.4 °F | 78.7 °F | 4.47 in. |
| October | 46.0 °F | 66.8 °F | 4.06 in. |
| November | 36.2 °F | 55.4 °F | 3.23 in. |
| December | 29.2 °F | 45.4 °F | 4.15 in. |
| Annual | 45.1 °F | 64.4 °F | 47.68 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |