Flash Flood Warning — Cook County, IL 8:30 PM Flash Flood Warning — Cook County, IL 10:00 PM Areal Flood Warning — Cook County, IL, De Kalb County, IL, DuPage County, IL, Kane County, IL 11:00 AM Areal Flood Warning — Cook County, IL, DuPage County, IL, Kane County, IL, Kendall County, IL, Will County, IL 2:00 PM

Cook County, Illinois, United States

Last updated: 7:10 PM CDT  ·  Refresh
23°C
Feels like 26°
Rain
▲ 28°  /  ▼ 18°
Wind
7 mph NE
Humidity
95%
Dew Point
21°
Pressure
29.28 inHg
Visibility
8 mi
UV Index
1.0
Cloud Cover
97%
Sunrise
5:21 AM
Sunset
8:29 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Cook County is currently rain at 23°C. Precipitation is likely — peak probability 66% around 7 PM. Sunrise: 5:21AM · Sunset: 8:29PM.

Alerts

Flash Flood Warning
Cook County, IL
Expires 8:30 PM
Flash Flood Warning
Cook County, IL
Expires 10:00 PM
Areal Flood Warning
Cook County, IL, De Kalb County, IL, DuPage County, IL, Kane County, IL
Expires 11:00 AM
Areal Flood Warning
Cook County, IL, DuPage County, IL, Kane County, IL, Kendall County, IL, Will County, IL
Expires 2:00 PM
52 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
23°
66%
8 PM
23°
63%
9 PM
22°
46%
10 PM
22°
39%
11 PM
21°
41%
12 AM
21°
35%
1 AM
21°
11%
2 AM
21°
11%
3 AM
21°
11%
4 AM
20°
12%
5 AM
18°
12%
6 AM
18°
23%
7 AM
19°
28%
8 AM
19°
32%
9 AM
20°
23%
10 AM
21°
32%
11 AM
21°
32%
12 PM
21°
28%
1 PM
22°
28%
2 PM
23°
28%
3 PM
23°
28%
4 PM
23°
18%
5 PM
24°
24%
6 PM
23°
20%
7-Day Forecast
Tonight
28° 18°
Rain, 66% chance.
Sun
25° 18°
Mostly Cloudy with a 32% chance of rain.
Mon
25° 19°
Mostly Clear.
Tue
28° 18°
Partly Cloudy.
Wed
28° 19°
Mostly Clear with a 43% chance of rain.
Thu
25° 20°
Rain, 82% chance.
Fri
25° 18°
Clear with a 30% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 23° Rain 66% 7 mph NE 95%
8 PM 23° Overcast 63% 5 mph NE 93%
9 PM 22° Overcast 46% 5 mph NE 94%
10 PM 22° Overcast 39% 5 mph NNE 95%
11 PM 21° Overcast 41% 4 mph NNE 95%
12 AM 21° Overcast 35% 4 mph NNE 95%
1 AM 21° Overcast 11% 4 mph N 96%
2 AM 21° Mostly Cloudy 11% 5 mph N 95%
3 AM 21° Mostly Cloudy 11% 4 mph NNW 94%
4 AM 20° Mostly Cloudy 12% 4 mph NNW 93%
5 AM 18° Mostly Cloudy 12% 4 mph NNW 92%
6 AM 18° Overcast 23% 4 mph NNW 90%
7 AM 19° Fog 28% 5 mph NNW 88%
8 AM 19° Mostly Cloudy 32% 5 mph N 87%
9 AM 20° Mostly Cloudy 23% 6 mph N 86%
10 AM 21° Mostly Cloudy 32% 7 mph N 84%
11 AM 21° Mostly Cloudy 32% 7 mph NNE 83%
12 PM 21° Overcast 28% 8 mph NNE 82%
1 PM 22° Overcast 28% 8 mph NNE 82%
2 PM 23° Mostly Cloudy 28% 8 mph NNE 80%
3 PM 23° Mostly Cloudy 28% 8 mph NNE 78%
4 PM 23° Mostly Cloudy 18% 8 mph NNE 76%
5 PM 24° Partly Cloudy 24% 9 mph NNE 77%
6 PM 23° Partly Cloudy 20% 9 mph NNE 78%
15-Day Forecast
Today
7/4
Rain
66%
18°
28°
Sun
7/5
Mostly Cloudy
32%
18°
25°
Mon
7/6
Mostly Clear
7%
19°
25°
Tue
7/7
Partly Cloudy
7%
18°
28°
Wed
7/8
Mostly Clear
43%
19°
28°
Thu
7/9
Rain
82%
20°
25°
Fri
7/10
Clear
30%
18°
25°
Sat
7/11
Clear
53%
19°
25°
Sun
7/12
Clear
43%
18°
26°
Mon
7/13
Partly Cloudy
44%
18°
26°
Tue
7/14
Overcast
44%
19°
28°
Wed
7/15
Drizzle
60%
19°
28°
Thu
7/16
Drizzle
60%
19°
25°
Fri
7/17
Drizzle
60%
19°
25°
Sat
7/18
Drizzle
60%
20°
26°
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 9.8 µg/m³
O3
Ground-level ozone
39 AQI 43 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 52 Moderate 39 52
Mon 39 Good 38 39
Tue 51 Moderate 34 51
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 Sat Jul 4, 22:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE572 J/kg
MLCAPE1042 J/kg
MUCAPE1437 J/kg
SBCIN-108 J/kg
MLCIN0 J/kg
Lifted Index-3.6
Kinematics
0–6 km Shear26 kt
0–1 km Shear3 kt
Eff. Shear28 kt
0–1 km SRH-17
0–3 km SRH-29
Eff. SRH-29
Storm Motion165° @ 17 kt
0–1 km EHI-0.1
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index41.6
Thermo & Levels
PWAT2.19 in
0–3 km LR5.2 °C/km
700–500 LR6.1 °C/km
Total Totals51.7
LCL966 hPa
LFC762 hPa
EL298 hPa
Freezing Lvl13,435 ft