Flood Warning — Cook County, IL, Lake County, IN 10:00 AM Flood Warning — Cook County, IL 2:51 PM Beach Hazards Statement — Lake, IL, Northern Cook, IL, Central Cook, IL, Lake, IN, Porter, IN 10:00 AM

Cook County, Illinois, United States

Last updated: 9:29 PM CDT  ·  Refresh
25°C
Feels like 28°
Partly Cloudy
▲ 27°  /  ▼ 21°
Wind
8 mph SSW
Humidity
87%
Dew Point
23°
Pressure
29.00 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
40%
Sunrise
5:40 AM
Sunset
8:14 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Cook County is currently partly cloudy at 25°C. Precipitation is likely — peak probability 57% around 10 PM. Atmospheric instability is elevated (CAPE up to 1985 J/kg) — isolated convective development possible. Sunrise: 5:40AM · Sunset: 8:14PM.

Alerts

Flood Warning
Cook County, IL, Lake County, IN
Expires 10:00 AM
Flood Warning
Cook County, IL
Expires 2:51 PM
Beach Hazards Statement
Lake, IL, Northern Cook, IL, Central Cook, IL, Lake, IN, Porter, IN
Expires 10:00 AM
54 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
25°
45%
10 PM
26°
56%
11 PM
26°
53%
12 AM
26°
33%
1 AM
25°
5%
2 AM
24°
5%
3 AM
23°
6%
4 AM
23°
6%
5 AM
21°
6%
6 AM
21°
3%
7 AM
21°
3%
8 AM
22°
3%
9 AM
22°
3%
10 AM
23°
3%
11 AM
23°
3%
12 PM
24°
3%
1 PM
22°
3%
2 PM
22°
3%
3 PM
22°
3%
4 PM
21°
3%
5 PM
23°
3%
6 PM
22°
3%
7 PM
22°
3%
8 PM
21°
3%
7-Day Forecast
Tonight
27° 21°
Partly Cloudy with a 45% chance of rain.
Tue
26° 21°
Partly Cloudy with a 33% chance of rain.
Wed
28° 19°
Clear.
Thu
29° 22°
Partly Cloudy with a 21% chance of rain.
Fri
25° 18°
Rain, 72% chance.
Sat
27° 19°
Rain, 90% chance.
Sun
27° 20°
Clear.
TimeTempConditionsPrecipWindHumidity
Now 25° Partly Cloudy 45% 8 mph SSW 87%
10 PM 26° Rain 56% 8 mph SW 87%
11 PM 26° Mostly Clear 53% 9 mph WSW 82%
12 AM 26° Mostly Clear 33% 8 mph W 76%
1 AM 25° Partly Cloudy 5% 7 mph NW 76%
2 AM 24° Partly Cloudy 5% 9 mph NNW 81%
3 AM 23° Mostly Cloudy 6% 12 mph N 86%
4 AM 23° Overcast 6% 13 mph N 89%
5 AM 21° Overcast 6% 12 mph N 88%
6 AM 21° Mostly Cloudy 3% 12 mph N 87%
7 AM 21° Mostly Cloudy 3% 12 mph N 85%
8 AM 22° Mostly Cloudy 3% 12 mph N 81%
9 AM 22° Mostly Cloudy 3% 12 mph N 77%
10 AM 23° Mostly Cloudy 3% 13 mph N 73%
11 AM 23° Mostly Cloudy 3% 13 mph N 70%
12 PM 24° Partly Cloudy 3% 12 mph N 67%
1 PM 22° Partly Cloudy 3% 13 mph N 62%
2 PM 22° Mostly Clear 3% 13 mph N 56%
3 PM 22° Mostly Clear 3% 13 mph N 51%
4 PM 21° Mostly Clear 3% 13 mph N 48%
5 PM 23° Mostly Clear 3% 13 mph N 50%
6 PM 22° Mostly Clear 3% 13 mph N 52%
7 PM 22° Mostly Clear 3% 12 mph N 54%
8 PM 21° Partly Cloudy 3% 12 mph N 56%
15-Day Forecast
Today
7/27
Partly Cloudy
45%
21°
27°
Tue
7/28
Partly Cloudy
33%
21°
26°
Wed
7/29
Clear
7%
19°
28°
Thu
7/30
Partly Cloudy
21%
22°
29°
Fri
7/31
Rain
72%
18°
25°
Sat
8/1
Rain
90%
19°
27°
Sun
8/2
Clear
17%
20°
27°
Mon
8/3
Clear
8%
19°
28°
Tue
8/4
Drizzle
44%
21°
29°
Wed
8/5
Drizzle
66%
22°
31°
Thu
8/6
Drizzle
60%
21°
31°
Fri
8/7
Drizzle
60%
21°
31°
Sat
8/8
Drizzle
60%
21°
26°
Sun
8/9
Drizzle
60%
21°
26°
Mon
8/10
Drizzle
60%
21°
26°
54
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
54 AQI 10.6 µg/m³
O3
Ground-level ozone
41 AQI 45 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 54 Moderate 41 54
Wed 31 Good 31 21
Thu 36 Good 35 36
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 90 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE1128 J/kg
MLCAPE1958 J/kg
MUCAPE3417 J/kg
SBCIN0 J/kg
MLCIN0 J/kg
Lifted Index-4.4
Kinematics
0–6 km Shear52 kt
0–1 km Shear23 kt
Eff. Shear57 kt
0–1 km SRH208
0–3 km SRH124
Eff. SRH124
Storm Motion280° @ 35 kt
0–1 km EHI1.5
Composite Parameters
Sig. Tornado2.4
STP (eff)1.6
Supercell12.4
K-Index29.6
Thermo & Levels
PWAT1.77 in
0–3 km LR4.4 °C/km
700–500 LR6.6 °C/km
Total Totals51.7
LCL955 hPa
LFC982 hPa
EL224 hPa
Freezing Lvl16,060 ft