Grundy County, Illinois, United States

Last updated: 9:31 PM CDT  ·  Refresh
27°C
Feels like 30°
Partly Cloudy
▲ 30°  /  ▼ 21°
Wind
9 mph SSW
Humidity
84%
Dew Point
24°
Pressure
29.05 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
31%
Sunrise
5:44 AM
Sunset
8:15 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Grundy County is currently partly cloudy at 27°C. Precipitation is likely — peak probability 54% around 11 PM. Atmospheric instability is elevated (CAPE up to 2748 J/kg) — isolated convective development possible. Sunrise: 5:44AM · Sunset: 8:15PM.

Alerts

No active alerts for this location.
37 AQI · Good Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
27°
13%
10 PM
27°
40%
11 PM
27°
53%
12 AM
26°
14%
1 AM
26°
3%
2 AM
24°
3%
3 AM
23°
3%
4 AM
22°
3%
5 AM
21°
3%
6 AM
21°
3%
7 AM
21°
3%
8 AM
22°
3%
9 AM
23°
3%
10 AM
24°
3%
11 AM
24°
3%
12 PM
26°
3%
1 PM
24°
3%
2 PM
25°
3%
3 PM
25°
3%
4 PM
26°
3%
5 PM
26°
3%
6 PM
26°
3%
7 PM
24°
3%
8 PM
23°
3%
7-Day Forecast
Tonight
30° 21°
Partly Cloudy.
Tue
28° 17°
Partly Cloudy.
Wed
28° 15°
Clear.
Thu
29° 18°
Partly Cloudy.
Fri
23° 17°
Rain, 58% chance.
Sat
27° 17°
Rain, 82% chance.
Sun
27° 16°
Clear.
TimeTempConditionsPrecipWindHumidity
Now 27° Partly Cloudy 13% 9 mph SSW 84%
10 PM 27° Mostly Cloudy 40% 10 mph SW 89%
11 PM 27° Partly Cloudy 53% 9 mph WSW 90%
12 AM 26° Partly Cloudy 14% 8 mph W 90%
1 AM 26° Partly Cloudy 3% 9 mph WNW 89%
2 AM 24° Partly Cloudy 3% 9 mph NW 88%
3 AM 23° Partly Cloudy 3% 9 mph NNW 90%
4 AM 22° Mostly Clear 3% 10 mph N 91%
5 AM 21° Partly Cloudy 3% 11 mph N 90%
6 AM 21° Mostly Cloudy 3% 11 mph N 89%
7 AM 21° Mostly Cloudy 3% 11 mph N 88%
8 AM 22° Mostly Cloudy 3% 11 mph N 86%
9 AM 23° Mostly Cloudy 3% 11 mph N 84%
10 AM 24° Mostly Cloudy 3% 11 mph N 81%
11 AM 24° Mostly Cloudy 3% 11 mph N 77%
12 PM 26° Mostly Cloudy 3% 11 mph N 73%
1 PM 24° Partly Cloudy 3% 11 mph N 70%
2 PM 25° Partly Cloudy 3% 11 mph N 67%
3 PM 25° Partly Cloudy 3% 11 mph N 64%
4 PM 26° Mostly Clear 3% 10 mph N 64%
5 PM 26° Mostly Clear 3% 10 mph N 66%
6 PM 26° Mostly Clear 3% 10 mph NNE 68%
7 PM 24° Mostly Clear 3% 10 mph NNE 69%
8 PM 23° Mostly Clear 3% 9 mph NNE 68%
15-Day Forecast
Today
7/27
Partly Cloudy
13%
21°
30°
Tue
7/28
Partly Cloudy
14%
17°
28°
Wed
7/29
Clear
7%
15°
28°
Thu
7/30
Partly Cloudy
14%
18°
29°
Fri
7/31
Rain
58%
17°
23°
Sat
8/1
Rain
82%
17°
27°
Sun
8/2
Clear
17%
16°
27°
Mon
8/3
Clear
17%
16°
27°
Tue
8/4
Drizzle
44%
18°
29°
Wed
8/5
Drizzle
44%
19°
29°
Thu
8/6
Rain
64%
18°
30°
Fri
8/7
Drizzle
60%
17°
30°
Sat
8/8
Drizzle
60%
18°
26°
Sun
8/9
Drizzle
60%
18°
26°
Mon
8/10
Drizzle
60%
18°
26°
37
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
37 AQI 6.7 µg/m³
O3
Ground-level ozone
36 AQI 40 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 37 Good 36 37
Wed 44 Good 44 38
Thu 44 Good 44 40
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 Tue Jul 28, 01:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 50 60 70 80 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE1722 J/kg
MLCAPE3176 J/kg
MUCAPE4291 J/kg
SBCIN-256 J/kg
MLCIN0 J/kg
Lifted Index-5.3
Kinematics
0–6 km Shear45 kt
0–1 km Shear19 kt
Eff. Shear62 kt
0–1 km SRH103
0–3 km SRH24
Eff. SRH-18
Storm Motion282° @ 36 kt
0–1 km EHI1.1
Composite Parameters
Sig. Tornado1.5
STP (eff)0.0
Supercell0.0
K-Index7.7
Thermo & Levels
PWAT1.64 in
0–3 km LR4.3 °C/km
700–500 LR7.2 °C/km
Total Totals52.4
LCL939 hPa
LFC656 hPa
EL172 hPa
Freezing Lvl16,152 ft