Dewey County Climate
Dewey County, South Dakota
Avg Annual Temp
45.3°F
Annual Precip
19.3"
Annual Snowfall
39.0"
Extreme Heat Days
24.3
days >= 90°F/yr
Monthly Temperature
Precipitation Calendar
Seasonal Overview
National Comparison
Climate Profile
About Dewey County Weather
Dry Air and Wide Temperature Swings
Dewey County averages 45.3°F annually, falling short of the national median but following the regional trend. This semi-arid climate features lower humidity and significant variation between day and night.
Tracking with the State Average
The county tracks very closely with the South Dakota average of 45.6°F. It represents the typical thermal experience for the central part of the state throughout the year.
Drier than Average Conditions
With 19.3 inches of annual precipitation, Dewey is drier than the state average of 22.7 inches. This dry air allows for 24 days of 90-degree heat while keeping snowfall to a modest 39.0 inches.
Hot Summers and Cold Winters
The seasons fluctuate from a July average of 72.7°F down to a January average of 16.9°F. Summer days are frequently hot, but the low 19.5°F winter average ensures a true northern winter experience.
Landscaping for a Semi-Arid Zone
Practical planning involves drought-resistant landscaping and efficient cooling for the 24 days of extreme summer heat. Winter preparations should focus on wind protection, as the open landscape offers little buffer from the cold.
Frequently Asked Questions
What is the average temperature in Dewey County?
How much rain does Dewey County get?
Does it snow in Dewey County?
How hot does Dewey County get in summer?
How cold are winters in Dewey County?
Track your own weather in Dewey County
Ambient Weather personal weather stations give you hyperlocal climate data.
Sponsored
Data source: NOAA National Centers for Environmental Information (NCEI), U.S. Climate Normals 1991-2020.
Climate normals are 30-year averages of weather variables computed from 1991 to 2020. Station data is aggregated to county level using spatial averaging. Data is informational only — not a substitute for official National Weather Service forecasts or emergency weather warnings.