Union County, SD Weather Forecast
County weather hub
Slight Chance Showers And Thunderstorms
Compare major city weather across Union County, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
A slight chance of showers and thunderstorms. Partly sunny, with a high near 78.
County Weather Overview
This county weather page brings together forecast coverage for Union County so visitors can compare temperatures, wind, and conditions across the region without hopping between unrelated pages.
Current forecast coverage spans 3 of 3 mapped cities in Union County.
Page Snapshot
- Page focus
- county weather
- Forecast window
- May 30, 2026
- Latest sync
- May 24, 2026 10:35 AM CDT
- Forecast office
- FSD
- Source
- NOAA / NWS
Daily Outlook
This Week in Union County
Saturday looks like the warmest upcoming period in Union County at 78 degrees F.
Saturday Night is the coolest period ahead with temperatures near 53 degrees F.
The strongest winds are forecast for Saturday at about 10 to 15 mph SE.
Precipitation is mentioned in 2 upcoming forecast periods.
Forecast Details
- Last updated
- May 24, 2026 10:35 AM CDT
- Coverage
- 1 day
- Time zone
- America/Chicago
- Forecast office
- FSD
- Radar station
- KFSD
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 53.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Saturday
May 30
|
Slight Chance Showers And Thunderstorms
|
78°F |
10 to 15 mph
SE
|
|
Saturday Night
May 30
|
Slight Chance Showers And Thunderstorms
|
53°F |
5 to 15 mph
SE
|
Major City Forecasts
Live forecast snapshots for major cities across Union County.
Coverage
Forecast coverage currently spans 3 of 3 mapped cities in Union County.
Largest mapped city population in this region: 2,928.
