Heat Advisory — McPherson, SD, Brown, SD, Marshall, SD, Roberts, SD, Edmunds, SD, Day, SD, Clark, SD, Grant, SD, Deuel, SD, Corson, SD, Campbell, SD, Walworth, SD, Dewey, SD, Potter, SD, Faulk, SD, Spink, SD, Stanley, SD, Sully, SD, Hughes, SD, Hyde, SD, Hand, SD, Jones, SD, Lyman, SD, Buffalo, SD 9:00 PM

Lyman County, South Dakota, United States

Last updated: 6:20 PM CDT  ·  Refresh
36°C
Feels like 36°
Mostly Clear
▲ 37°  /  ▼ 21°
Wind
17 mph SE
Humidity
32%
Dew Point
18°
Pressure
28.03 inHg
Visibility
10 mi
UV Index
5.7
Cloud Cover
17%
Sunrise
6:24 AM
Sunset
9:06 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Lyman County is currently mostly clear at 36°C. Precipitation is likely — peak probability 87% around 6 PM. Atmospheric instability is elevated (CAPE up to 1495 J/kg) — isolated convective development possible. Sunrise: 6:24AM · Sunset: 9:06PM.

Alerts

Heat Advisory
McPherson, SD, Brown, SD, Marshall, SD, Roberts, SD, Edmunds, SD, Day, SD, Clark, SD, Grant, SD, Deuel, SD, Corson, SD, Campbell, SD, Walworth, SD, Dewey, SD, Potter, SD, Faulk, SD, Spink, SD, Stanley, SD, Sully, SD, Hughes, SD, Hyde, SD, Hand, SD, Jones, SD, Lyman, SD, Buffalo, SD
Expires 9:00 PM
60 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
36°
15%
7 PM
34°
33%
8 PM
33°
33%
9 PM
30°
35%
10 PM
29°
31%
11 PM
27°
36%
12 AM
26°
35%
1 AM
25°
33%
2 AM
26°
34%
3 AM
24°
38%
4 AM
23°
35%
5 AM
23°
36%
6 AM
21°
45%
7 AM
21°
54%
8 AM
22°
55%
9 AM
23°
62%
10 AM
24°
66%
11 AM
24°
69%
12 PM
24°
70%
1 PM
25°
73%
2 PM
27°
77%
3 PM
28°
77%
4 PM
28°
78%
5 PM
27°
74%
7-Day Forecast
Tonight
37° 21°
Mostly Clear with a 35% chance of rain.
Thu
32° 18°
Rain, 86% chance.
Fri
31° 17°
Mostly Clear with a 42% chance of rain.
Sat
32° 17°
Clear.
Sun
38° 18°
Partly Cloudy.
Mon
37° 21°
Rain, 49% chance.
Tue
28° 14°
Drizzle, 63% chance.
TimeTempConditionsPrecipWindHumidity
Now 36° Mostly Clear 15% 17 mph SE 32%
7 PM 34° Mostly Clear 33% 14 mph SE 33%
8 PM 33° Partly Cloudy 33% 13 mph SE 38%
9 PM 30° Partly Cloudy 35% 12 mph SE 43%
10 PM 29° Mostly Cloudy 31% 12 mph SE 48%
11 PM 27° Overcast 36% 11 mph SE 53%
12 AM 26° Overcast 35% 11 mph SSE 60%
1 AM 25° Overcast 33% 11 mph S 66%
2 AM 26° Drizzle 34% 11 mph S 71%
3 AM 24° Overcast 38% 10 mph S 75%
4 AM 23° Overcast 35% 10 mph S 78%
5 AM 23° Overcast 36% 9 mph S 80%
6 AM 21° Rain 45% 9 mph SSW 82%
7 AM 21° Rain 54% 9 mph SSW 82%
8 AM 22° Heavy Rain 55% 8 mph S 76%
9 AM 23° Rain 62% 8 mph S 71%
10 AM 24° Mostly Cloudy 66% 9 mph SSE 67%
11 AM 24° Rain 69% 8 mph SSE 68%
12 PM 24° Heavy Rain 70% 8 mph SSE 69%
1 PM 25° Heavy Rain 73% 8 mph SSE 70%
2 PM 27° Mostly Cloudy 77% 7 mph SE 66%
3 PM 28° Mostly Cloudy 77% 6 mph SE 62%
4 PM 28° Partly Cloudy 78% 6 mph ESE 62%
5 PM 27° Partly Cloudy 74% 6 mph ESE 68%
15-Day Forecast
Today
7/29
Mostly Clear
35%
21°
37°
Thu
7/30
Rain
86%
18°
32°
Fri
7/31
Mostly Clear
42%
17°
31°
Sat
8/1
Clear
5%
17°
32°
Sun
8/2
Partly Cloudy
3%
18°
38°
Mon
8/3
Rain
49%
21°
37°
Tue
8/4
Drizzle
63%
14°
28°
Wed
8/5
Clear
24%
13°
29°
Thu
8/6
Mostly Clear
35%
15°
32°
Fri
8/7
Clear
35%
19°
34°
Sat
8/8
Clear
36%
16°
33°
Sun
8/9
Drizzle
60%
20°
32°
Mon
8/10
Drizzle
60%
20°
33°
Tue
8/11
Drizzle
60%
21°
33°
Wed
8/12
Drizzle
60%
22°
34°
60
Moderate
U.S. Air Quality Index · Dominant: PM2.5
50 100 150 200

Air quality is acceptable. Unusually sensitive people should consider limiting prolonged outdoor exertion.

Pollutant Breakdown · Today
PM2.5
Fine particulate matter
Dominant
60 AQI 14.0 µg/m³
O3
Ground-level ozone
49 AQI 53 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Thu 60 Moderate 49 60
Fri 53 Moderate 43 53
Sat 58 Moderate 46 58
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 29, 22:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 50 60 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE1578 J/kg
MLCAPE1406 J/kg
MUCAPE1578 J/kg
SBCIN0 J/kg
MLCIN0 J/kg
Lifted Index-5.1
Kinematics
0–6 km Shear32 kt
0–1 km Shear2 kt
Eff. Shear34 kt
0–1 km SRH14
0–3 km SRH-6
Eff. SRH-6
Storm Motion220° @ 19 kt
0–1 km EHI0.1
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index38.3
Thermo & Levels
PWAT1.51 in
0–3 km LR8.6 °C/km
700–500 LR6.5 °C/km
Total Totals52.2
LCL737 hPa
LFC949 hPa
EL185 hPa
Freezing Lvl14,537 ft