Massac County, Illinois, United States

Last updated: 10:04 PM CDT  ·  Refresh
27°C
Feels like 30°
Partly Cloudy
▲ 34°  /  ▼ 20°
Wind
5 mph N
Humidity
80%
Dew Point
23°
Pressure
29.42 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
54%
Sunrise
5:51 AM
Sunset
8:11 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Massac County is currently partly cloudy at 26°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 551 J/kg) — isolated convective development possible. Sunrise: 5:51AM · Sunset: 8:11PM.

Alerts

No active alerts for this location.
45 AQI · Good Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
27°
3%
11 PM
25°
14%
12 AM
24°
14%
1 AM
23°
3%
2 AM
23°
3%
3 AM
22°
3%
4 AM
21°
3%
5 AM
20°
3%
6 AM
20°
3%
7 AM
20°
3%
8 AM
21°
3%
9 AM
23°
3%
10 AM
24°
3%
11 AM
26°
3%
12 PM
26°
3%
1 PM
29°
3%
2 PM
28°
3%
3 PM
28°
3%
4 PM
28°
3%
5 PM
28°
3%
6 PM
28°
3%
7 PM
27°
3%
8 PM
26°
3%
9 PM
23°
3%
7-Day Forecast
Tonight
34° 20°
Partly Cloudy.
Wed
29° 18°
Partly Cloudy.
Thu
27° 16°
Clear.
Fri
25° 16°
Overcast with a 44% chance of rain.
Sat
30° 18°
Clear with a 45% chance of rain.
Sun
33° 23°
Clear.
Mon
33° 23°
Clear.
TimeTempConditionsPrecipWindHumidity
Now 27° Partly Cloudy 3% 5 mph N 80%
11 PM 25° Mostly Clear 14% 5 mph N 85%
12 AM 24° Clear 14% 6 mph N 86%
1 AM 23° Partly Cloudy 3% 6 mph N 87%
2 AM 23° Partly Cloudy 3% 6 mph N 88%
3 AM 22° Mostly Clear 3% 6 mph N 90%
4 AM 21° Clear 3% 5 mph N 92%
5 AM 20° Clear 3% 6 mph N 91%
6 AM 20° Clear 3% 6 mph NNW 91%
7 AM 20° Clear 3% 6 mph N 90%
8 AM 21° Clear 3% 8 mph N 85%
9 AM 23° Clear 3% 7 mph N 81%
10 AM 24° Mostly Clear 3% 7 mph N 76%
11 AM 26° Mostly Clear 3% 8 mph N 71%
12 PM 26° Partly Cloudy 3% 9 mph N 67%
1 PM 29° Partly Cloudy 3% 10 mph N 63%
2 PM 28° Partly Cloudy 3% 10 mph N 63%
3 PM 28° Mostly Cloudy 3% 10 mph N 63%
4 PM 28° Mostly Cloudy 3% 10 mph NNE 64%
5 PM 28° Partly Cloudy 3% 10 mph NNE 66%
6 PM 28° Partly Cloudy 3% 9 mph NNE 68%
7 PM 27° Mostly Clear 3% 9 mph NNE 71%
8 PM 26° Mostly Clear 3% 9 mph NNE 72%
9 PM 23° Mostly Clear 3% 8 mph NNE 74%
15-Day Forecast
Today
7/21
Partly Cloudy
3%
20°
34°
Wed
7/22
Partly Cloudy
3%
18°
29°
Thu
7/23
Clear
3%
16°
27°
Fri
7/24
Overcast
44%
16°
25°
Sat
7/25
Clear
45%
18°
30°
Sun
7/26
Clear
17%
23°
33°
Mon
7/27
Clear
17%
23°
33°
Tue
7/28
Clear
17%
20°
32°
Wed
7/29
Drizzle
44%
18°
29°
Thu
7/30
Drizzle
44%
16°
29°
Fri
7/31
Drizzle
51%
16°
29°
Sat
8/1
Drizzle
60%
18°
30°
Sun
8/2
Drizzle
60%
19°
31°
Mon
8/3
Drizzle
60%
19°
31°
Tue
8/4
Drizzle
60%
20°
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 8.2 µg/m³
O3
Ground-level ozone
31 AQI 33 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 45 Good 31 45
Thu 26 Good 26 18
Fri 29 Good 29 7
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 22, 01:00'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
SBCAPE738 J/kg
MLCAPE12 J/kg
MUCAPE738 J/kg
SBCIN-167 J/kg
MLCIN0 J/kg
Lifted Index-0.6
Kinematics
0–6 km Shear42 kt
0–1 km Shear15 kt
Eff. Shear46 kt
0–1 km SRH-136
0–3 km SRH-140
Eff. SRH-140
Storm Motion280° @ 30 kt
0–1 km EHI-0.6
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index3.0
Thermo & Levels
PWAT1.31 in
0–3 km LR4.7 °C/km
700–500 LR5.2 °C/km
Total Totals36.9
LCL949 hPa
LFC804 hPa
EL170 hPa
Freezing Lvl17,700 ft