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Active Weather Warnings

Weather in Berwyn, Illinois

12:54 PM
Now
Cloudy Weather
63° F
Feels Like 59°
Precipitation 45 %
Wind 15 mph
UV Index (0 - 11+) 1
Humidity 78 %
Today
Rainy Weather
Day 64°
Night 55°
Precipitation 89 %
Wind 14 mph
UV Index (0 - 11+) 4

Berwyn Weather Forecast Updated

30 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (September 21, 2025)

Day

84°

Night

68°

Air Quality in Berwyn

NOW
24 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 2.52 µg/m³
PM10 2.78 µg/m³
O3 0.025 ppm
NO2 3.3 ppb
SO2 1.1 ppb
CO 0.18 ppm
NH3 0.48 µg/m³
NO 0.91 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.52.52 µg/m³
PM102.78 µg/m³
O349.9 µg/m³
NO26.12 µg/m³
SO22.87 µg/m³
CO200.73 µg/m³
NH30.48 µg/m³
NO0.91 µg/m³

Weather Alerts and Warnings for Berwyn

Severe Future Possible

Flood Watch

Flood Watch issued September 19 at 10:03PM CDT until September 22 at 7:00AM CDT by NWS Chicago IL
Sep 20, 10:00 AM Sep 22, 7:00 AM
...The Flood Watch continues for the following rivers in Illinois...

Des Plaines River near Russell affecting Lake IL zone.

Des Plaines River near Des Plaines affecting Northern Cook and
Central Cook zones.

Des Plaines River near Gurnee affecting Lake IL zone.

Des Plaines River at Riverside affecting Central Cook zone.

Des Plaines River at Lincolnshire affecting Northern Cook and Lake
IL zones.

.The combination of heavy rain this morning and expected additional
thunderstorms with heavy rain tonight may lead to river flooding
along the Des Plaines River basin as early as Sunday morning. The
heavy rain tonight is expected to occur along a roughly west to east
axis across northern Illinois, though the exact location across the
river basin remains uncertain. Flooding severity may be higher or
lower over the basin depending on the ultimate placement of the
highest rainfall tonight.

WHAT: Flooding is possible.

WHERE: Des Plaines River from Roosevelt Road in Forest Park
downstream to Hodgkins, including the Riverside gauge.

WHEN: From Sunday morning to Tuesday morning.

ADDITIONAL DETAILS:
- At 8:45 PM CDT Saturday the stage was 3.6 feet.
- Forecast...Rises on the river are possible over the next few
days. The river may reach flood stage.
- Flood stage is 7.5 feet.
- http://www.weather.gov/safety/flood
+ Read More
A Flood Watch means water levels above flood stage are possible, but not yet certain, based upon the latest forecasts. Persons along rivers and streams in the watch area should monitor the latest forecasts and be prepared to take action should flooding develop. These forecasts are based on observed precipitation as well as forecast precipitation 24 hours into the future. Changes to the rainfall forecast, or any additional rainfall after 24 hours, may cause changes to these river forecasts. Additional information is available at www.weather.gov. The next statement will be issued by Sunday afternoon.
Updated: Sep 20, 8:37 AM Source: NWS Alert
Moderate Expected Likely

Beach Hazards Statement

Beach Hazards Statement issued September 21 at 9:25AM CDT until September 23 at 7:00PM CDT by NWS Chicago IL
Sep 21, 9:25 AM Sep 23, 7:00 PM
WHAT: High wave action and dangerous currents expected at Lake
Michigan beaches. Waves 5 to 8 ft expected.

WHERE: Lake IL, Northern Cook and Central Cook Counties.

WHEN: Through Wednesday evening.

IMPACTS: Swimming conditions will be life threatening,
especially for inexperienced swimmers.
+ Read More
Remain out of the water to avoid dangerous swimming conditions and do not venture out onto piers, jetties, breakwalls, or other shoreline structures.
Updated: Sep 21, 12:23 PM Source: NWS Alert