Union County, South Dakota, United States

Last updated: 10:38 PM CDT  ·  Refresh
27°C
Feels like 28°
Clear
▲ 34°  /  ▼ 19°
Wind
7 mph S
Humidity
62%
Dew Point
20°
Pressure
28.53 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
0%
Sunrise
6:03 AM
Sunset
9:01 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Union County is currently clear at 27°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 988 J/kg) — isolated convective development possible. Sunrise: 6:03AM · Sunset: 9:01PM.

Alerts

No active alerts for this location.
49 AQI · Good Dominant: O3 Air Quality
Hourly Forecast · Next 24 Hours
Now
27°
3%
11 PM
27°
14%
12 AM
26°
7%
1 AM
24°
3%
2 AM
24°
3%
3 AM
23°
3%
4 AM
23°
3%
5 AM
19°
3%
6 AM
19°
3%
7 AM
21°
3%
8 AM
22°
3%
9 AM
24°
3%
10 AM
26°
3%
11 AM
26°
3%
12 PM
27°
3%
1 PM
31°
3%
2 PM
31°
3%
3 PM
32°
3%
4 PM
32°
3%
5 PM
32°
3%
6 PM
32°
3%
7 PM
31°
3%
8 PM
29°
3%
9 PM
28°
3%
7-Day Forecast
Tonight
34° 19°
Clear.
Sat
33° 19°
Partly Cloudy.
Sun
37° 20°
Clear with a 38% chance of rain.
Mon
41° 22°
Mostly Clear.
Tue
30° 16°
Clear.
Wed
24° 11°
Drizzle, 51% chance.
Thu
27° 13°
Clear with a 52% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 27° Clear 3% 7 mph S 62%
11 PM 27° Clear 14% 8 mph SSW 62%
12 AM 26° Clear 7% 8 mph SSW 65%
1 AM 24° Clear 3% 6 mph SSW 68%
2 AM 24° Clear 3% 4 mph S 71%
3 AM 23° Clear 3% 2 mph SE 74%
4 AM 23° Clear 3% 3 mph E 76%
5 AM 19° Mostly Clear 3% 4 mph E 77%
6 AM 19° Partly Cloudy 3% 4 mph ENE 78%
7 AM 21° Partly Cloudy 3% 7 mph ENE 76%
8 AM 22° Partly Cloudy 3% 9 mph ENE 70%
9 AM 24° Partly Cloudy 3% 10 mph ENE 65%
10 AM 26° Partly Cloudy 3% 10 mph ENE 61%
11 AM 26° Partly Cloudy 3% 10 mph ENE 58%
12 PM 27° Partly Cloudy 3% 10 mph ENE 54%
1 PM 31° Partly Cloudy 3% 10 mph ENE 51%
2 PM 31° Partly Cloudy 3% 10 mph ENE 47%
3 PM 32° Partly Cloudy 3% 10 mph ENE 44%
4 PM 32° Partly Cloudy 3% 10 mph ENE 43%
5 PM 32° Partly Cloudy 3% 10 mph ENE 43%
6 PM 32° Partly Cloudy 3% 11 mph ENE 43%
7 PM 31° Partly Cloudy 3% 10 mph ENE 47%
8 PM 29° Mostly Clear 3% 10 mph ENE 52%
9 PM 28° Mostly Clear 3% 10 mph ENE 58%
15-Day Forecast
Today
7/17
Clear
3%
19°
34°
Sat
7/18
Partly Cloudy
3%
19°
33°
Sun
7/19
Clear
38%
20°
37°
Mon
7/20
Mostly Clear
14%
22°
41°
Tue
7/21
Clear
7%
16°
30°
Wed
7/22
Drizzle
51%
11°
24°
Thu
7/23
Clear
52%
13°
27°
Fri
7/24
Clear
31%
16°
29°
Sat
7/25
Drizzle
44%
13°
32°
Sun
7/26
Rain
68%
16°
33°
Mon
7/27
Drizzle
60%
16°
32°
Tue
7/28
Drizzle
60%
20°
36°
Wed
7/29
Drizzle
60%
20°
36°
Thu
7/30
Drizzle
60%
21°
36°
Fri
7/31
Clear
60%
21°
36°
49
Good
U.S. Air Quality Index · Dominant: O3
50 100 150 200

Air quality is satisfactory and poses little or no health risk.

Pollutant Breakdown · Today
PM2.5
Fine particulate matter
39 AQI 7.1 µg/m³
O3
Ground-level ozone
Dominant
49 AQI 53 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 49 Good 49 39
Sun 40 Good 40 33
Mon 43 Good 43 27
About the Air Quality Index
0–50 Good
51–100 Moderate
101–150 Unhealthy for Sensitive Groups
151–200 Unhealthy
201–300 Very Unhealthy
301–500 Hazardous

The U.S. AQI runs 0–500. The overall value equals the highest individual pollutant sub-index, and the dominant pollutant is the one driving it. PM2.5 (fine particles) is reported in µg/m³ and ozone (O3) in ppb. Forecast source: NWS NAQFC.

1000850700500400300250200150100 -40-30-20-10010203040 0.41247101624 LCLLFCEL0°C Temperature (°C) Pressure (hPa)
Temp Dewpoint Parcel (SB) CAPE CIN Dry adiabat Moist adiabat Mixing ratio
RAP
Valid Sat Jul 18, 02:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE360 J/kg
MLCAPE735 J/kg
MUCAPE1326 J/kg
SBCIN-385 J/kg
MLCIN0 J/kg
Lifted Index-1.5
Kinematics
0–6 km Shear12 kt
0–1 km Shear15 kt
Eff. Shear24 kt
0–1 km SRH82
0–3 km SRH47
Eff. SRH-3
Storm Motion258° @ 19 kt
0–1 km EHI0.2
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index33.3
Thermo & Levels
PWAT1.49 in
0–3 km LR5.6 °C/km
700–500 LR5.8 °C/km
Total Totals46.0
LCL872 hPa
LFC603 hPa
EL201 hPa
Freezing Lvl15,469 ft