Union County, South Dakota, United States

Last updated: 9:40 PM CDT  ·  Refresh
28°C
Feels like 30°
Clear
▲ 34°  /  ▼ 20°
Wind
7 mph S
Humidity
56%
Dew Point
20°
Pressure
28.53 inHg
Visibility
9 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 29°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 1000 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
28°
3%
10 PM
28°
14%
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
20°
3%
6 AM
20°
3%
7 AM
21°
3%
8 AM
22°
3%
9 AM
24°
5%
10 AM
26°
5%
11 AM
26°
3%
12 PM
27°
3%
1 PM
30°
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%
7-Day Forecast
Tonight
34° 20°
Clear.
Sat
33° 20°
Partly Cloudy.
Sun
36° 19°
Mostly Clear with a 34% chance of rain.
Mon
41° 22°
Clear.
Tue
31° 16°
Clear.
Wed
24° 11°
Rain, 64% chance.
Thu
27° 13°
Clear with a 52% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 28° Clear 3% 7 mph S 56%
10 PM 28° Clear 14% 8 mph S 59%
11 PM 27° Clear 14% 8 mph SSW 62%
12 AM 26° Clear 7% 7 mph SSW 65%
1 AM 24° Clear 3% 6 mph SSW 68%
2 AM 24° Clear 3% 4 mph S 70%
3 AM 23° Clear 3% 2 mph ESE 73%
4 AM 23° Mostly Clear 3% 3 mph E 74%
5 AM 20° Partly Cloudy 3% 4 mph E 76%
6 AM 20° Partly Cloudy 3% 5 mph ENE 77%
7 AM 21° Partly Cloudy 3% 7 mph ENE 74%
8 AM 22° Partly Cloudy 3% 9 mph ENE 69%
9 AM 24° Partly Cloudy 5% 11 mph ENE 63%
10 AM 26° Partly Cloudy 5% 10 mph ENE 59%
11 AM 26° Partly Cloudy 3% 10 mph ENE 56%
12 PM 27° Partly Cloudy 3% 10 mph ENE 53%
1 PM 30° Partly Cloudy 3% 10 mph ENE 49%
2 PM 31° Partly Cloudy 3% 10 mph ENE 46%
3 PM 32° Partly Cloudy 3% 10 mph ENE 43%
4 PM 32° Partly Cloudy 3% 11 mph ENE 41%
5 PM 32° Partly Cloudy 3% 10 mph ENE 41%
6 PM 32° Partly Cloudy 3% 10 mph ENE 40%
7 PM 31° Partly Cloudy 3% 10 mph ENE 45%
8 PM 29° Partly Cloudy 3% 10 mph ENE 51%
15-Day Forecast
Today
7/17
Clear
3%
20°
34°
Sat
7/18
Partly Cloudy
7%
20°
33°
Sun
7/19
Mostly Clear
34%
19°
36°
Mon
7/20
Clear
14%
22°
41°
Tue
7/21
Clear
8%
16°
31°
Wed
7/22
Rain
64%
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
Drizzle
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, 01:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE662 J/kg
MLCAPE580 J/kg
MUCAPE1314 J/kg
SBCIN-302 J/kg
MLCIN0 J/kg
Lifted Index-2.2
Kinematics
0–6 km Shear12 kt
0–1 km Shear13 kt
Eff. Shear22 kt
0–1 km SRH71
0–3 km SRH22
Eff. SRH-23
Storm Motion260° @ 19 kt
0–1 km EHI0.3
Composite Parameters
Sig. Tornado0.1
STP (eff)0.0
Supercell0.0
K-Index36.5
Thermo & Levels
PWAT1.44 in
0–3 km LR6.4 °C/km
700–500 LR5.5 °C/km
Total Totals46.5
LCL850 hPa
LFC722 hPa
EL195 hPa
Freezing Lvl15,466 ft