Excessive Heat Warning — Corson, SD, Campbell, SD, Walworth, SD, Dewey, SD, Potter, SD, McPherson, SD, Brown, SD, Marshall, SD, Roberts, SD, Edmunds, SD, Day, SD, Faulk, SD, Spink, SD, Grant, SD, Stanley, SD, Sully, SD, Hughes, SD, Hyde, SD, Hand, SD, Jones, SD, Lyman, SD, Buffalo, SD 10:00 PM Heat Advisory — McPherson, SD, Brown, SD, Marshall, SD, Roberts, SD, Edmunds, SD, Day, SD, Faulk, SD, Spink, SD, Grant, SD, Corson, SD, Campbell, SD, Walworth, SD, Dewey, SD, Potter, SD, Stanley, SD, Sully, SD, Hughes, SD, Hyde, SD, Hand, SD, Jones, SD, Lyman, SD, Buffalo, SD 10:00 PM

Day County, South Dakota, United States

Last updated: 5:03 PM CDT  ·  Refresh
31°C
Feels like 31°
Clear
▲ 33°  /  ▼ 19°
Wind
9 mph SE
Humidity
42%
Dew Point
18°
Pressure
28.19 inHg
Visibility
10 mi
UV Index
7.4
Cloud Cover
4%
Sunrise
5:56 AM
Sunset
9:15 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Day County is currently clear at 31°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 696 J/kg) — isolated convective development possible. Sunrise: 5:56AM · Sunset: 9:15PM.

Alerts

Excessive Heat Warning
Corson, SD, Campbell, SD, Walworth, SD, Dewey, SD, Potter, SD, McPherson, SD, Brown, SD, Marshall, SD, Roberts, SD, Edmunds, SD, Day, SD, Faulk, SD, Spink, SD, Grant, SD, Stanley, SD, Sully, SD, Hughes, SD, Hyde, SD, Hand, SD, Jones, SD, Lyman, SD, Buffalo, SD
Expires 10:00 PM
Heat Advisory
McPherson, SD, Brown, SD, Marshall, SD, Roberts, SD, Edmunds, SD, Day, SD, Faulk, SD, Spink, SD, Grant, SD, Corson, SD, Campbell, SD, Walworth, SD, Dewey, SD, Potter, SD, Stanley, SD, Sully, SD, Hughes, SD, Hyde, SD, Hand, SD, Jones, SD, Lyman, SD, Buffalo, SD
Expires 10:00 PM
32 AQI · Good Dominant: O3 Air Quality
Hourly Forecast · Next 24 Hours
Now
31°
3%
6 PM
33°
3%
7 PM
32°
3%
8 PM
31°
3%
9 PM
29°
3%
10 PM
27°
3%
11 PM
26°
3%
12 AM
24°
3%
1 AM
24°
3%
2 AM
23°
3%
3 AM
22°
3%
4 AM
22°
3%
5 AM
21°
3%
6 AM
19°
3%
7 AM
19°
3%
8 AM
22°
3%
9 AM
24°
3%
10 AM
24°
3%
11 AM
26°
3%
12 PM
27°
3%
1 PM
28°
3%
2 PM
29°
3%
3 PM
29°
3%
4 PM
31°
3%
7-Day Forecast
Today
33° 19°
Clear.
Thu
33° 19°
Clear.
Fri
34° 21°
Clear.
Sat
30° 19°
Partly Cloudy.
Sun
35° 19°
Partly Cloudy.
Mon
34° 18°
Clear.
Tue
29° 17°
Mostly Clear.
TimeTempConditionsPrecipWindHumidity
Now 31° Clear 3% 9 mph SE 42%
6 PM 33° Clear 3% 9 mph SSE 43%
7 PM 32° Clear 3% 8 mph SE 46%
8 PM 31° Clear 3% 7 mph SE 51%
9 PM 29° Mostly Clear 3% 7 mph SE 56%
10 PM 27° Clear 3% 8 mph SE 61%
11 PM 26° Clear 3% 7 mph SE 66%
12 AM 24° Clear 3% 8 mph SE 69%
1 AM 24° Clear 3% 8 mph SSE 72%
2 AM 23° Clear 3% 7 mph SSE 75%
3 AM 22° Clear 3% 7 mph SSE 77%
4 AM 22° Clear 3% 7 mph SSE 80%
5 AM 21° Clear 3% 7 mph SSE 80%
6 AM 19° Clear 3% 7 mph SSE 80%
7 AM 19° Clear 3% 8 mph SSE 78%
8 AM 22° Clear 3% 9 mph S 71%
9 AM 24° Clear 3% 10 mph S 64%
10 AM 24° Clear 3% 10 mph S 58%
11 AM 26° Clear 3% 10 mph S 53%
12 PM 27° Clear 3% 10 mph S 48%
1 PM 28° Clear 3% 10 mph S 45%
2 PM 29° Clear 3% 10 mph S 44%
3 PM 29° Clear 3% 9 mph S 42%
4 PM 31° Mostly Clear 3% 9 mph S 41%
15-Day Forecast
Today
7/15
Clear
3%
19°
33°
Thu
7/16
Clear
3%
19°
33°
Fri
7/17
Clear
3%
21°
34°
Sat
7/18
Partly Cloudy
8%
19°
30°
Sun
7/19
Partly Cloudy
19%
19°
35°
Mon
7/20
Clear
9%
18°
34°
Tue
7/21
Mostly Clear
9%
17°
29°
Wed
7/22
Mostly Cloudy
60%
16°
29°
Thu
7/23
Drizzle
60%
17°
31°
Fri
7/24
Drizzle
60%
17°
32°
Sat
7/25
Drizzle
60%
11°
32°
Sun
7/26
Drizzle
60%
18°
32°
Mon
7/27
Drizzle
60%
18°
32°
Tue
7/28
Drizzle
60%
18°
33°
Wed
7/29
Drizzle
60%
19°
34°
32
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
31 AQI 5.7 µg/m³
O3
Ground-level ozone
Dominant
32 AQI 35 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Thu 32 Good 32 31
Fri 36 Good 36 33
Sat 44 Good 41 44
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 Wed Jul 15, 20:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE801 J/kg
MLCAPE154 J/kg
MUCAPE801 J/kg
SBCIN0 J/kg
MLCIN0 J/kg
Lifted Index-0.5
Kinematics
0–6 km Shear35 kt
0–1 km Shear3 kt
Eff. Shear35 kt
0–1 km SRH1
0–3 km SRH-19
Eff. SRH-19
Storm Motion188° @ 26 kt
0–1 km EHI0.0
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index22.9
Thermo & Levels
PWAT1.09 in
0–3 km LR7.5 °C/km
700–500 LR4.6 °C/km
Total Totals39.5
LCL793 hPa
LFC954 hPa
EL199 hPa
Freezing Lvl16,227 ft