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

Massac County, Illinois, United States

Last updated: 2:25 AM CDT  ·  Refresh
25°C
Feels like 28°
Clear
▲ 37°  /  ▼ 23°
Wind
2 mph SSE
Humidity
80%
Dew Point
22°
Pressure
29.52 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
0%
Sunrise
6:28 AM
Sunset
7:18 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Massac County is currently clear at 25°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 2562 J/kg) — isolated convective development possible. Sunrise: 6:28AM · Sunset: 7:18PM.

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
56 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
25°
10%
3 AM
24°
4%
4 AM
24°
4%
5 AM
23°
4%
6 AM
23°
4%
7 AM
23°
9%
8 AM
26°
16%
9 AM
29°
17%
10 AM
32°
15%
11 AM
33°
15%
12 PM
34°
16%
1 PM
36°
16%
2 PM
36°
18%
3 PM
36°
19%
4 PM
36°
19%
5 PM
36°
19%
6 PM
35°
14%
7 PM
34°
9%
8 PM
33°
9%
9 PM
28°
9%
10 PM
27°
19%
11 PM
27°
19%
12 AM
27°
19%
1 AM
27°
20%
7-Day Forecast
Today
37° 23°
Clear.
Sat
38° 23°
Mostly Clear with a 51% chance of rain.
Sun
37° 19°
Clear with a 43% chance of rain.
Mon
33° 14°
Clear.
Tue
38° 19°
Clear.
Wed
41° 22°
Clear with a 28% chance of rain.
Thu
38° 20°
Clear with a 28% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 25° Clear 10% 2 mph SSE 80%
3 AM 24° Clear 4% 2 mph SE 81%
4 AM 24° Clear 4% 3 mph ESE 82%
5 AM 23° Clear 4% 3 mph SE 83%
6 AM 23° Clear 4% 3 mph SSE 84%
7 AM 23° Clear 9% 3 mph SSE 82%
8 AM 26° Clear 16% 3 mph S 74%
9 AM 29° Clear 17% 4 mph SSW 66%
10 AM 32° Clear 15% 4 mph SSW 58%
11 AM 33° Clear 15% 4 mph SW 52%
12 PM 34° Clear 16% 4 mph SW 47%
1 PM 36° Clear 16% 3 mph SW 44%
2 PM 36° Clear 18% 3 mph SSW 44%
3 PM 36° Clear 19% 4 mph S 44%
4 PM 36° Clear 19% 5 mph SSE 45%
5 PM 36° Clear 19% 4 mph S 49%
6 PM 35° Clear 14% 3 mph S 54%
7 PM 34° Clear 9% 3 mph S 58%
8 PM 33° Clear 9% 3 mph SSE 61%
9 PM 28° Clear 9% 3 mph SSE 64%
10 PM 27° Clear 19% 3 mph SSE 66%
11 PM 27° Clear 19% 3 mph SSE 68%
12 AM 27° Clear 19% 2 mph S 70%
1 AM 27° Clear 20% 2 mph S 72%
15-Day Forecast
Today
9/4
Clear
19%
23°
37°
Sat
9/5
Mostly Clear
51%
23°
38°
Sun
9/6
Clear
43%
19°
37°
Mon
9/7
Clear
3%
14°
33°
Tue
9/8
Clear
3%
19°
38°
Wed
9/9
Clear
28%
22°
41°
Thu
9/10
Clear
28%
20°
38°
Fri
9/11
Drizzle
43%
17°
38°
Sat
9/12
Clear
44%
21°
43°
Sun
9/13
Drizzle
51%
18°
37°
Mon
9/14
Clear
60%
21°
37°
Tue
9/15
Drizzle
60%
22°
37°
Wed
9/16
Drizzle
60%
21°
37°
Thu
9/17
Drizzle
60%
19°
34°
Fri
9/18
Clear
25%
19°
34°
56
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
56 AQI 11.7 µg/m³
O3
Ground-level ozone
49 AQI 53 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 56 Moderate 49 56
Sat 61 Moderate 50 61
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
SBCAPE557 J/kg
MLCAPE905 J/kg
MUCAPE1248 J/kg
SBCIN-391 J/kg
MLCIN-164 J/kg
Lifted Index-1.6
Kinematics
0–6 km Shear3 kt
0–1 km Shear12 kt
Eff. Shear2 kt
0–1 km SRH28
0–3 km SRH13
Eff. SRH-3
Storm Motion318° @ 9 kt
0–1 km EHI0.1
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index34.3
Thermo & Levels
PWAT1.70 in
0–3 km LR4.8 °C/km
700–500 LR5.4 °C/km
Total Totals46.7
LCL962 hPa
LFC715 hPa
EL244 hPa
Freezing Lvl16,306 ft