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 Flood Warning — Cook County, IL 8:12 PM

Cook County, Illinois, United States

Last updated: 9:22 PM CDT  ·  Refresh
21°C
Feels like 23°
Mostly Cloudy
▲ 28°  /  ▼ 18°
Wind
5 mph NE
Humidity
98%
Dew Point
20°
Pressure
29.29 inHg
Visibility
8 mi
UV Index
0.0
Cloud Cover
74%
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 mostly cloudy at 21°C. Precipitation is likely — peak probability 71% around 9 PM. Sunrise: 5:21AM · Sunset: 8:29PM.

Alerts

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
Flood Warning
Cook County, IL
Expires 8:12 PM
52 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
21°
70%
10 PM
21°
58%
11 PM
21°
56%
12 AM
21°
35%
1 AM
21°
23%
2 AM
21°
27%
3 AM
21°
38%
4 AM
20°
38%
5 AM
18°
37%
6 AM
18°
45%
7 AM
18°
32%
8 AM
19°
32%
9 AM
19°
23%
10 AM
20°
32%
11 AM
21°
35%
12 PM
21°
43%
1 PM
23°
39%
2 PM
23°
39%
3 PM
23°
39%
4 PM
23°
29%
5 PM
23°
28%
6 PM
22°
21%
7 PM
22°
20%
8 PM
22°
20%
7-Day Forecast
Tonight
28° 18°
Mostly Cloudy with a 70% chance of rain.
Sun
25° 18°
Mostly Cloudy with a 45% chance of rain.
Mon
24° 19°
Mostly Clear.
Tue
27° 18°
Clear.
Wed
28° 19°
Rain, 72% chance.
Thu
23° 18°
Rain, 71% chance.
Fri
24° 17°
Clear with a 31% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 21° Mostly Cloudy 70% 5 mph NE 98%
10 PM 21° Mostly Cloudy 58% 5 mph NNE 96%
11 PM 21° Mostly Cloudy 56% 5 mph NNE 96%
12 AM 21° Mostly Cloudy 35% 5 mph NNE 96%
1 AM 21° Overcast 23% 4 mph N 95%
2 AM 21° Overcast 27% 4 mph NNW 95%
3 AM 21° Overcast 38% 4 mph NNW 94%
4 AM 20° Overcast 38% 5 mph NNW 94%
5 AM 18° Overcast 37% 5 mph NNW 93%
6 AM 18° Overcast 45% 5 mph N 93%
7 AM 18° Overcast 32% 5 mph N 92%
8 AM 19° Overcast 32% 6 mph N 91%
9 AM 19° Overcast 23% 7 mph N 89%
10 AM 20° Overcast 32% 8 mph N 88%
11 AM 21° Mostly Cloudy 35% 8 mph N 86%
12 PM 21° Mostly Cloudy 43% 8 mph N 83%
1 PM 23° Partly Cloudy 39% 10 mph N 81%
2 PM 23° Mostly Cloudy 39% 10 mph NNE 80%
3 PM 23° Mostly Cloudy 39% 10 mph NNE 80%
4 PM 23° Mostly Cloudy 29% 10 mph NNE 79%
5 PM 23° Mostly Cloudy 28% 10 mph NNE 78%
6 PM 22° Partly Cloudy 21% 10 mph NNE 78%
7 PM 22° Partly Cloudy 20% 10 mph NNE 78%
8 PM 22° Partly Cloudy 20% 9 mph NNE 79%
15-Day Forecast
Today
7/4
Mostly Cloudy
70%
18°
28°
Sun
7/5
Mostly Cloudy
45%
18°
25°
Mon
7/6
Mostly Clear
6%
19°
24°
Tue
7/7
Clear
3%
18°
27°
Wed
7/8
Rain
72%
19°
28°
Thu
7/9
Rain
71%
18°
23°
Fri
7/10
Clear
31%
17°
24°
Sat
7/11
Clear
53%
18°
25°
Sun
7/12
Drizzle
43%
17°
26°
Mon
7/13
Clear
44%
16°
27°
Tue
7/14
Clear
60%
21°
28°
Wed
7/15
Drizzle
60%
21°
28°
Thu
7/16
Drizzle
60%
21°
26°
Fri
7/17
Drizzle
60%
21°
26°
Sat
7/18
Drizzle
60%
21°
27°
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 Sun Jul 5, 01:00'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
SBCAPE41 J/kg
MLCAPE54 J/kg
MUCAPE330 J/kg
SBCIN-0 J/kg
MLCIN0 J/kg
Lifted Index-0.1
Kinematics
0–6 km Shear13 kt
0–1 km Shear10 kt
Eff. Shear15 kt
0–1 km SRH23
0–3 km SRH15
Eff. SRH-25
Storm Motion175° @ 17 kt
0–1 km EHI0.0
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index38.3
Thermo & Levels
PWAT2.14 in
0–3 km LR4.7 °C/km
700–500 LR5.3 °C/km
Total Totals46.2
LCL983 hPa
LFC954 hPa
EL485 hPa
Freezing Lvl14,196 ft