Severe Thunderstorm Watch 12:00 AM

Cook County, Illinois, United States

Last updated: 10:09 PM CDT  ·  Refresh
22°C
Feels like 24°
Partly Cloudy
▲ 27°  /  ▼ 17°
Wind
5 mph SW
Humidity
91%
Dew Point
20°
Pressure
29.28 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
50%
Sunrise
6:05 AM
Sunset
7:41 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Cook County is currently partly cloudy at 22°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 1303 J/kg) — isolated convective development possible. Sunrise: 6:05AM · Sunset: 7:41PM.

Alerts

Severe Thunderstorm Watch
Expires 12:00 AM
55 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
22°
33%
11 PM
23°
35%
12 AM
23°
22%
1 AM
21°
7%
2 AM
21°
8%
3 AM
20°
18%
4 AM
20°
18%
5 AM
19°
18%
6 AM
19°
15%
7 AM
19°
15%
8 AM
19°
22%
9 AM
21°
10%
10 AM
22°
18%
11 AM
23°
19%
12 PM
25°
23%
1 PM
27°
28%
2 PM
27°
33%
3 PM
27°
33%
4 PM
27°
23%
5 PM
28°
12%
6 PM
27°
10%
7 PM
27°
3%
8 PM
26°
3%
9 PM
24°
3%
7-Day Forecast
Tonight
27° 17°
Partly Cloudy with a 33% chance of rain.
Sat
28° 18°
Partly Cloudy with a 28% chance of rain.
Sun
25° 17°
Partly Cloudy.
Mon
24° 14°
Mostly Cloudy with a 37% chance of rain.
Tue
27° 17°
Rain, 64% chance.
Wed
28° 16°
Thunderstorm, 64% chance.
Thu
29° 19°
Drizzle, 52% chance.
TimeTempConditionsPrecipWindHumidity
Now 22° Partly Cloudy 33% 5 mph SW 91%
11 PM 23° Partly Cloudy 35% 4 mph SW 92%
12 AM 23° Partly Cloudy 22% 5 mph SW 93%
1 AM 21° Partly Cloudy 7% 5 mph WSW 93%
2 AM 21° Partly Cloudy 8% 5 mph WSW 92%
3 AM 20° Mostly Clear 18% 5 mph W 91%
4 AM 20° Partly Cloudy 18% 6 mph WNW 91%
5 AM 19° Partly Cloudy 18% 7 mph NW 90%
6 AM 19° Partly Cloudy 15% 8 mph NW 89%
7 AM 19° Partly Cloudy 15% 9 mph NW 87%
8 AM 19° Partly Cloudy 22% 10 mph NW 80%
9 AM 21° Partly Cloudy 10% 10 mph NNW 73%
10 AM 22° Partly Cloudy 18% 11 mph NW 66%
11 AM 23° Partly Cloudy 19% 11 mph NW 60%
12 PM 25° Partly Cloudy 23% 11 mph NW 54%
1 PM 27° Partly Cloudy 28% 11 mph NW 49%
2 PM 27° Partly Cloudy 33% 10 mph NW 50%
3 PM 27° Partly Cloudy 33% 10 mph NW 50%
4 PM 27° Partly Cloudy 23% 10 mph NW 50%
5 PM 28° Partly Cloudy 12% 10 mph NW 51%
6 PM 27° Partly Cloudy 10% 10 mph NW 52%
7 PM 27° Partly Cloudy 3% 9 mph NW 55%
8 PM 26° Partly Cloudy 3% 8 mph NW 60%
9 PM 24° Partly Cloudy 3% 7 mph NW 65%
15-Day Forecast
Today
8/21
Partly Cloudy
33%
17°
27°
Sat
8/22
Partly Cloudy
28%
18°
28°
Sun
8/23
Partly Cloudy
3%
17°
25°
Mon
8/24
Mostly Cloudy
37%
14°
24°
Tue
8/25
Rain
64%
17°
27°
Wed
8/26
Thunderstorm
64%
16°
28°
Thu
8/27
Drizzle
52%
19°
29°
Fri
8/28
Drizzle
53%
20°
28°
Sat
8/29
Rain
68%
19°
29°
Sun
8/30
Rain
68%
21°
28°
Mon
8/31
Drizzle
60%
21°
33°
Tue
9/1
Drizzle
60%
21°
33°
Wed
9/2
Drizzle
60%
20°
27°
Thu
9/3
Drizzle
60%
20°
26°
Fri
9/4
Drizzle
60%
19°
27°
55
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
55 AQI 11.4 µg/m³
O3
Ground-level ozone
39 AQI 43 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 55 Moderate 39 55
Sun 33 Good 33 26
Mon 26 Good 26 14
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 Aug 22, 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
SBCAPE1312 J/kg
MLCAPE1496 J/kg
MUCAPE1862 J/kg
SBCIN-90 J/kg
MLCIN-34 J/kg
Lifted Index-4.3
Kinematics
0–6 km Shear31 kt
0–1 km Shear18 kt
Eff. Shear28 kt
0–1 km SRH129
0–3 km SRH164
Eff. SRH164
Storm Motion333° @ 15 kt
0–1 km EHI1.1
Composite Parameters
Sig. Tornado0.6
STP (eff)0.8
Supercell4.5
K-Index35.3
Thermo & Levels
PWAT1.66 in
0–3 km LR5.7 °C/km
700–500 LR6.4 °C/km
Total Totals52.6
LCL955 hPa
LFC819 hPa
EL222 hPa
Freezing Lvl12,313 ft