Heat Advisory — Jefferson, IL, Wayne, IL, Edwards, IL, Wabash, 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

Jefferson County, Illinois, United States

Last updated: 8:07 AM CDT  ·  Refresh
26°C
Feels like 28°
Mostly Clear
▲ 34°  /  ▼ 24°
Wind
10 mph SW
Humidity
83%
Dew Point
23°
Pressure
29.51 inHg
Visibility
10 mi
UV Index
5.2
Cloud Cover
26%
Sunrise
6:06 AM
Sunset
7:55 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Jefferson County is currently mostly clear at 26°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 3682 J/kg) — isolated convective development possible. Sunrise: 6:06AM · Sunset: 7:55PM.

Alerts

Heat Advisory
Jefferson, IL, Wayne, IL, Edwards, IL, Wabash, 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
45 AQI · Good Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
26°
15%
9 AM
27°
23%
10 AM
29°
23%
11 AM
31°
23%
12 PM
32°
21%
1 PM
33°
3%
2 PM
33°
3%
3 PM
33°
3%
4 PM
33°
4%
5 PM
34°
4%
6 PM
34°
4%
7 PM
33°
4%
8 PM
32°
5%
9 PM
29°
5%
10 PM
28°
5%
11 PM
28°
5%
12 AM
28°
5%
1 AM
28°
5%
2 AM
27°
5%
3 AM
27°
5%
4 AM
27°
5%
5 AM
26°
5%
6 AM
25°
5%
7 AM
24°
5%
7-Day Forecast
Today
34° 24°
Partly Cloudy with a 23% chance of rain.
Tue
36° 24°
Mostly Clear.
Wed
37° 24°
Partly Cloudy with a 74% chance of rain.
Thu
33° 23°
Overcast with a 81% chance of rain.
Fri
31° 22°
Drizzle, 69% chance.
Sat
34° 22°
Drizzle, 46% chance.
Sun
34° 23°
Mostly Clear with a 31% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 26° Mostly Clear 15% 10 mph SW 83%
9 AM 27° Partly Cloudy 23% 11 mph SW 74%
10 AM 29° Partly Cloudy 23% 12 mph SW 68%
11 AM 31° Partly Cloudy 23% 12 mph SW 64%
12 PM 32° Partly Cloudy 21% 12 mph SW 60%
1 PM 33° Partly Cloudy 3% 12 mph SW 56%
2 PM 33° Partly Cloudy 3% 12 mph SW 55%
3 PM 33° Partly Cloudy 3% 12 mph SW 55%
4 PM 33° Partly Cloudy 4% 11 mph SW 54%
5 PM 34° Mostly Clear 4% 10 mph SW 58%
6 PM 34° Mostly Clear 4% 9 mph SSW 61%
7 PM 33° Partly Cloudy 4% 8 mph SSW 65%
8 PM 32° Partly Cloudy 5% 8 mph SSW 67%
9 PM 29° Partly Cloudy 5% 8 mph SSW 70%
10 PM 28° Partly Cloudy 5% 9 mph SSW 72%
11 PM 28° Partly Cloudy 5% 10 mph SSW 71%
12 AM 28° Partly Cloudy 5% 10 mph SSW 70%
1 AM 28° Partly Cloudy 5% 11 mph SSW 70%
2 AM 27° Partly Cloudy 5% 11 mph SSW 70%
3 AM 27° Partly Cloudy 5% 11 mph SSW 71%
4 AM 27° Partly Cloudy 5% 10 mph SSW 72%
5 AM 26° Partly Cloudy 5% 10 mph SSW 75%
6 AM 25° Partly Cloudy 5% 10 mph SSW 78%
7 AM 24° Mostly Clear 5% 10 mph SSW 80%
15-Day Forecast
Today
8/10
Partly Cloudy
23%
24°
34°
Tue
8/11
Mostly Clear
11%
24°
36°
Wed
8/12
Partly Cloudy
74%
24°
37°
Thu
8/13
Overcast
81%
23°
33°
Fri
8/14
Drizzle
69%
22°
31°
Sat
8/15
Drizzle
46%
22°
34°
Sun
8/16
Mostly Clear
31%
23°
34°
Mon
8/17
Drizzle
46%
21°
30°
Tue
8/18
Rain
53%
18°
31°
Wed
8/19
Thunderstorm
47%
21°
34°
Thu
8/20
Clear
60%
22°
33°
Fri
8/21
Drizzle
60%
21°
32°
Sat
8/22
Clear
60%
20°
31°
Sun
8/23
Drizzle
60%
20°
32°
Mon
8/24
Clear
60%
19°
31°
45
Good
U.S. Air Quality Index · Dominant: PM2.5
50 100 150 200

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

Pollutant Breakdown · Today
PM2.5
Fine particulate matter
Dominant
45 AQI 8.1 µg/m³
O3
Ground-level ozone
36 AQI 39 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Tue 45 Good 36 45
Wed 34 Good 34 21
Thu 42 Good 42 31
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 Mon Aug 10, 11:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 50 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE2029 J/kg
MLCAPE1560 J/kg
MUCAPE2029 J/kg
SBCIN-275 J/kg
MLCIN0 J/kg
Lifted Index-7.4
Kinematics
0–6 km Shear12 kt
0–1 km Shear26 kt
Eff. Shear17 kt
0–1 km SRH220
0–3 km SRH195
Eff. SRH23
Storm Motion332° @ 9 kt
0–1 km EHI2.8
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index30.3
Thermo & Levels
PWAT1.64 in
0–3 km LR4.6 °C/km
700–500 LR7.8 °C/km
Total Totals53.8
LCL959 hPa
LFC693 hPa
EL189 hPa
Freezing Lvl14,829 ft