Hazard Report Provided By forecast.weather.gov

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
1051 PM CDT Mon Jul 27 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-290400-
Winnebago-Boone-McHenry-Lake IL-Ogle-Lee-De Kalb-Kane-DuPage-
La Salle-Kendall-Grundy-Kankakee-Livingston-Iroquois-Ford-
Northern Cook-Central Cook-Southern Cook-Northern Will-
Southern Will-Eastern Will-Lake IN-Porter-Newton-Jasper-Benton-
1051 PM CDT Mon Jul 27 2026 /1151 PM EDT Mon Jul 27 2026/

This Hazardous Weather Outlook is for portions of north central
Illinois...northeast Illinois and northwest Indiana.

.DAY ONE...Tonight.

Weather hazards expected...

  Limited Thunderstorm Risk.
  High Swim Risk Lake Michigan Beaches.

DISCUSSION...

Isolated thunderstorms south of I-80 will end overnight.

Gusty northerly winds will lead to high waves and dangerous
swimming conditions at Lake Michigan beaches beginning late
tonight.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday through Wednesday morning...
  High Swim Risk Lake Michigan Beaches.
Friday...
  Elevated Flooding Risk.
  Limited Thunderstorm Risk.
Saturday and Sunday...
  Limited Thunderstorm Risk.

.SPOTTER INFORMATION STATEMENT...

  Spotter activation will not be necessary through tonight.

GENERAL STORM MOTION OF THE DAY:

  Moving toward the southeast at 30 mph.

$$

Coastal Hazard Message
National Weather Service Chicago IL
916 PM CDT Mon Jul 27 2026

ILZ006-103-104-INZ001-002-281030-
/O.CON.KLOT.BH.S.0009.000000T0000Z-260729T1500Z/
Lake IL-Northern Cook-Central Cook-Lake IN-Porter-
916 PM CDT Mon Jul 27 2026

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT THROUGH WEDNESDAY
MORNING...

* WHAT...High wave action and dangerous currents expected at Lake
  Michigan beaches. Waves 6 to 9 feet expected.

* WHERE...In Illinois, Lake, Northern Cook and Central Cook
  Counties. In Indiana, Lake and Porter Counties.

* WHEN...Through Wednesday morning.

* IMPACTS...Swimming conditions will be life threatening,
  especially for inexperienced swimmers. For information on swim
  advisories or bans at Chicago beaches: www. cpdbeaches. com.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain out of the water to avoid dangerous swimming conditions
and do not venture out onto piers, jetties, breakwalls, or other
shoreline structures.

&&

$$

Flood Statement
National Weather Service Chicago IL
759 PM CDT Mon Jul 27 2026

...The Flood Warning continues for the following rivers in
Illinois...Indiana...

  Little Calumet River at Munster (Hohman Avenue) affecting Cook
  and Lake IN Counties.

For the Little Calumet River...including Munster (Hohman Avenue)...
Minor flooding is forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Warning means water levels above flood stage are imminent or
may already be occurring. Persons along rivers and streams in the
warned area should take immediate precautions to protect life and
property.

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 Tuesday morning.

&&

ILC031-INC089-281500-
/O.EXT.KLOT.FL.W.0061.000000T0000Z-260728T1500Z/
/LCMI3.1.ER.260728T0450Z.260728T0600Z.260728T0900Z.NO/
759 PM CDT Mon Jul 27 2026

...FLOOD WARNING NOW IN EFFECT UNTIL LATE TUESDAY MORNING...

* WHAT...Minor flooding is forecast.

* WHERE...Little Calumet River from IN-912 in Hammond downstream to
  confluence with Thorn Creek in South Holland, including the
  Munster (Hohman Avenue) gauge.

* WHEN...Until late Tuesday morning.

* IMPACTS...At 12.5 feet, Most areas outside of the levee-protected
  area are inundated in Hammond and Munster.

* ADDITIONAL DETAILS...
  - At 7:00 PM CDT Monday the stage was 10.8 feet.
  - Forecast...The river is expected to rise above flood stage
    late this evening to a crest of 12.3 feet just after midnight
    tonight. It will then fall below flood stage Tuesday morning.
  - Flood stage is 12.0 feet.
  - http://www.weather.gov/safety/flood

&&

LAT...LON 4163 8756 4159 8740 4153 8743 4157 8758


$$

Flood Warning
National Weather Service Chicago IL
756 PM CDT Mon Jul 27 2026

...The National Weather Service in Chicago IL has issued a Flood
Warning for the following rivers in Illinois...

  Thorn Creek at Thornton affecting Cook County.

For the Thorn Creek...including Thornton...Minor flooding is
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Warning means water levels above flood stage are imminent or
may already be occurring. Persons along rivers and streams in the
warned area should take immediate precautions to protect life and
property.

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 Tuesday afternoon.

&&

ILC031-281900-
/O.NEW.KLOT.FL.W.0062.260728T0348Z-260728T1951Z/
/THNI2.1.ER.260728T0348Z.260728T0600Z.260728T1350Z.NO/
756 PM CDT Mon Jul 27 2026

...FLOOD WARNING IN EFFECT UNTIL EARLY TUESDAY AFTERNOON...

* WHAT...Minor flooding is forecast.

* WHERE...Thorn Creek from Near Glenwood downstream to confluence
  with Little Calumet River, including the Thornton gauge.

* WHEN...Until early Tuesday afternoon.

* IMPACTS...At 9.0 feet, Water begins to be diverted through Thorn
  Creek Diversion Tunnel.

* ADDITIONAL DETAILS...
  - At 7:45 PM CDT Monday the stage was 8.2 feet.
  - Forecast...The river is expected to rise above flood stage
    late this evening to a crest of 9.6 feet just after midnight
    tonight. It will then fall below flood stage Tuesday morning.
  - Flood stage is 9.0 feet.
  - http://www.weather.gov/safety/flood

&&

LAT...LON 4161 8760 4158 8754 4151 8760 4154 8767


$$

Hazard Report Provided By forecast.weather.gov