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Weather & Climate
Dewey County, South Dakota, United States
Overview
Climate data and monthly weather averages for Dewey County.
Key Metrics
Annual Avg
8.7°C
Summer Avg
23.3°C
Winter Avg
-5.7°C
Record High
46.5°C
Record Low
-31.2°C
Annual Precipitation
495.2 mm
Avg Humidity
66%
Summer Humidity
57%
Winter Humidity
78%
Monthly Averages
| Month | High (°C) | Avg (°C) | Low (°C) | Rain (mm) | Humidity (%) | Sunshine (h) | Wind (kph) |
|---|---|---|---|---|---|---|---|
| Jan | 12.5° | -6.5° | -31.2° | 9.6 | 80% | 57 | 70.8 |
| Feb | 19.8° | -5.5° | -27.4° | 16.5 | 75% | 82 | 70.9 |
| Mar | 27.3° | 1.5° | -29.4° | 23.6 | 68% | 118 | 67.1 |
| Apr | 31.8° | 7.9° | -12.1° | 48.6 | 62% | 149 | 63.5 |
| May | 36.6° | 14.6° | -3.7° | 81.2 | 60% | 184 | 59.1 |
| Jun | 44.1° | 21.2° | 4° | 81.3 | 59% | 202 | 63.1 |
| Jul | 46.5° | 25.4° | 9.3° | 63.9 | 54% | 214 | 51.2 |
| Aug | 42.4° | 23.2° | 8.5° | 58.3 | 57% | 178 | 60.2 |
| Sep | 39.6° | 17.6° | 1.2° | 44.1 | 59% | 133 | 66.1 |
| Oct | 33° | 8.4° | -17.6° | 41.5 | 65% | 89 | 70.2 |
| Nov | 22.5° | 1.2° | -18.1° | 12.3 | 72% | 57 | 70.4 |
| Dec | 12.1° | -5.1° | -28.4° | 14.3 | 80% | 44 | 66.5 |
Frequently Asked Questions
Sources: NASA POWER · Last updated: 2025
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