Astoria, South Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 33.2 °F (low) to 53 °F (high). Annual precipitation averages 27.7 Inches. Astoria is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.6 °F | 21.3 °F | 0.67 in. |
| February | 7.7 °F | 25.8 °F | 0.63 in. |
| March | 19.6 °F | 37.9 °F | 1.38 in. |
| April | 31.9 °F | 53.2 °F | 2.6 in. |
| May | 44.9 °F | 66.2 °F | 3.71 in. |
| June | 55.5 °F | 75.9 °F | 4.75 in. |
| July | 60.0 °F | 81.0 °F | 3.51 in. |
| August | 57.9 °F | 78.9 °F | 3.24 in. |
| September | 49.1 °F | 71.4 °F | 3.16 in. |
| October | 35.5 °F | 57.1 °F | 2.19 in. |
| November | 22.2 °F | 40.4 °F | 1.06 in. |
| December | 10.1 °F | 26.5 °F | 0.8 in. |
| Annual | 33.2 °F | 53 °F | 27.7 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |