Excessive Heat Warning — Jefferson, IL, Wayne, IL, Edwards, IL, Wabash, IL, Perry, IL, Franklin, IL, Hamilton, IL, White, IL, Jackson, IL, Williamson, IL, Saline, IL, Gallatin, IL, Union, IL, Johnson, IL, Pope, IL, Hardin, IL, Alexander, IL, Pulaski, IL, Massac, IL, Gibson, IN, Pike, IN, Posey, IN, Vanderburgh, IN, Warrick, IN, Spencer, IN, Fulton, KY, Hickman, KY, Carlisle, KY, Ballard, KY, McCracken, KY, Graves, KY, Livingston, KY, Marshall, KY, Calloway, KY, Crittenden, KY, Lyon, KY, Trigg, KY, Caldwell, KY, Union, KY, Webster, KY, Hopkins, KY, Christian, KY, Henderson, KY, Daviess, KY, McLean, KY, Muhlenberg, KY, Todd, KY, Perry, MO, Bollinger, MO, Cape Girardeau, MO, Wayne, MO, Carter, MO, Ripley, MO, Butler, MO, Stoddard, MO, Scott, MO, Mississippi, MO, New Madrid, MO 8:00 PM

Union County, Illinois, United States

Last updated: 2:24 AM CDT  ·  Refresh
26°C
Feels like 29°
Clear
▲ 37°  /  ▼ 23°
Wind
3 mph S
Humidity
79%
Dew Point
22°
Pressure
29.35 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
0%
Sunrise
6:29 AM
Sunset
7:21 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Union County is currently clear at 26°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 1929 J/kg) — isolated convective development possible. Sunrise: 6:29AM · Sunset: 7:21PM.

Alerts

Excessive Heat Warning
Jefferson, IL, Wayne, IL, Edwards, IL, Wabash, IL, Perry, IL, Franklin, IL, Hamilton, IL, White, IL, Jackson, IL, Williamson, IL, Saline, IL, Gallatin, IL, Union, IL, Johnson, IL, Pope, IL, Hardin, IL, Alexander, IL, Pulaski, IL, Massac, IL, Gibson, IN, Pike, IN, Posey, IN, Vanderburgh, IN, Warrick, IN, Spencer, IN, Fulton, KY, Hickman, KY, Carlisle, KY, Ballard, KY, McCracken, KY, Graves, KY, Livingston, KY, Marshall, KY, Calloway, KY, Crittenden, KY, Lyon, KY, Trigg, KY, Caldwell, KY, Union, KY, Webster, KY, Hopkins, KY, Christian, KY, Henderson, KY, Daviess, KY, McLean, KY, Muhlenberg, KY, Todd, KY, Perry, MO, Bollinger, MO, Cape Girardeau, MO, Wayne, MO, Carter, MO, Ripley, MO, Butler, MO, Stoddard, MO, Scott, MO, Mississippi, MO, New Madrid, MO
Expires 8:00 PM
52 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
26°
10%
3 AM
26°
9%
4 AM
25°
7%
5 AM
23°
7%
6 AM
23°
7%
7 AM
24°
14%
8 AM
27°
15%
9 AM
31°
15%
10 AM
33°
15%
11 AM
34°
18%
12 PM
34°
18%
1 PM
37°
27%
2 PM
37°
27%
3 PM
37°
19%
4 PM
37°
10%
5 PM
37°
10%
6 PM
36°
5%
7 PM
34°
5%
8 PM
33°
5%
9 PM
28°
5%
10 PM
28°
18%
11 PM
27°
18%
12 AM
27°
18%
1 AM
28°
18%
7-Day Forecast
Today
37° 23°
Mostly Clear with a 27% chance of rain.
Sat
39° 23°
Partly Cloudy with a 55% chance of rain.
Sun
38° 19°
Clear.
Mon
34° 14°
Mostly Clear.
Tue
38° 18°
Clear.
Wed
41° 22°
Clear with a 28% chance of rain.
Thu
38° 19°
Rain, 28% chance.
TimeTempConditionsPrecipWindHumidity
Now 26° Clear 10% 3 mph S 79%
3 AM 26° Clear 9% 3 mph S 79%
4 AM 25° Clear 7% 3 mph SSW 80%
5 AM 23° Clear 7% 3 mph S 80%
6 AM 23° Clear 7% 3 mph S 81%
7 AM 24° Clear 14% 3 mph S 79%
8 AM 27° Clear 15% 3 mph SSW 70%
9 AM 31° Clear 15% 4 mph SW 60%
10 AM 33° Clear 15% 4 mph SW 52%
11 AM 34° Clear 18% 4 mph SW 47%
12 PM 34° Mostly Clear 18% 4 mph SW 42%
1 PM 37° Partly Cloudy 27% 4 mph SSW 40%
2 PM 37° Partly Cloudy 27% 4 mph SSW 40%
3 PM 37° Partly Cloudy 19% 5 mph S 40%
4 PM 37° Partly Cloudy 10% 5 mph S 41%
5 PM 37° Mostly Clear 10% 5 mph S 44%
6 PM 36° Mostly Clear 5% 5 mph SSE 48%
7 PM 34° Clear 5% 5 mph SSE 53%
8 PM 33° Clear 5% 5 mph SSE 58%
9 PM 28° Clear 5% 5 mph SSE 62%
10 PM 28° Clear 18% 5 mph SSE 65%
11 PM 27° Clear 18% 5 mph SSE 67%
12 AM 27° Mostly Clear 18% 5 mph SSE 69%
1 AM 28° Mostly Clear 18% 5 mph SSE 70%
15-Day Forecast
Today
9/4
Mostly Clear
27%
23°
37°
Sat
9/5
Partly Cloudy
55%
23°
39°
Sun
9/6
Clear
13%
19°
38°
Mon
9/7
Mostly Clear
3%
14°
34°
Tue
9/8
Clear
3%
18°
38°
Wed
9/9
Clear
28%
22°
41°
Thu
9/10
Rain
28%
19°
38°
Fri
9/11
Rain
44%
17°
39°
Sat
9/12
Clear
44%
21°
43°
Sun
9/13
Clear
44%
18°
38°
Mon
9/14
Clear
25%
21°
37°
Tue
9/15
Drizzle
60%
22°
38°
Wed
9/16
Drizzle
60%
22°
37°
Thu
9/17
Drizzle
60%
20°
34°
Fri
9/18
Clear
25%
19°
34°
52
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
52 AQI 9.5 µg/m³
O3
Ground-level ozone
46 AQI 50 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 52 Moderate 46 52
Sat 56 Moderate 47 56
Sun 54 Moderate 45 54
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 Fri Sep 4, 06:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE752 J/kg
MLCAPE897 J/kg
MUCAPE1200 J/kg
SBCIN-333 J/kg
MLCIN-149 J/kg
Lifted Index-2.6
Kinematics
0–6 km Shear4 kt
0–1 km Shear10 kt
Eff. Shear6 kt
0–1 km SRH-0
0–3 km SRH-5
Eff. SRH-9
Storm Motion40° @ 8 kt
0–1 km EHI-0.0
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index36.3
Thermo & Levels
PWAT1.71 in
0–3 km LR5.2 °C/km
700–500 LR5.5 °C/km
Total Totals46.9
LCL950 hPa
LFC732 hPa
EL229 hPa
Freezing Lvl16,171 ft