Hazard Report Provided By forecast.weather.gov

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
342 PM CDT Wed Aug 12 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-132045-
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-
342 PM CDT Wed Aug 12 2026 /442 PM EDT Wed Aug 12 2026/

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

.DAY ONE...Tonight.

Weather hazards expected...

  Limited Fog Risk.

DISCUSSION...

Fog may become locally dense tonight.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Thursday and Friday...
  Elevated Flooding Risk.
  Limited Thunderstorm Risk...with an associated:
     Level 1 of 5 Severe Thunderstorm Risk.
Saturday...
  Elevated Flooding Risk.
  Limited Thunderstorm Risk.
Sunday...
  Limited Thunderstorm Risk.


DISCUSSION...

An active weather pattern with periodic thunderstorm chances is
expected to persist into the weekend. Some of these storms may be
strong to severe at times, as well as capable of producing heavy
rainfall which could lead to flash flooding.

.SPOTTER INFORMATION STATEMENT...

  Spotter activation will not be necessary through tonight.

$$

Flood Statement
National Weather Service Chicago IL
248 PM CDT Wed Aug 12 2026

...The Flood Warning is extended 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 Thursday morning.

&&

ILC031-131400-
/O.EXT.KLOT.FL.W.0068.000000T0000Z-260814T0000Z/
/THNI2.1.ER.260811T2331Z.260812T0830Z.260813T1800Z.NO/
248 PM CDT Wed Aug 12 2026

...FLOOD WARNING NOW IN EFFECT UNTIL THURSDAY EVENING...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

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

* WHEN...Until Thursday evening.

* IMPACTS...At 11.0 feet, 187th Street threatened in Glenwood.

* ADDITIONAL DETAILS...
  - At 2:30 PM CDT Wednesday the stage was 9.6 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 2:30 PM CDT Wednesday was 10.6 feet.
  - Forecast...The river is expected to rise to a crest around 10
    feet tonight. It will then fall below flood stage tomorrow
    afternoon.
  - Flood stage is 9.0 feet.
  - http://www.weather.gov/safety/flood

&&

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


$$

Carlaw

Hazard Report Provided By forecast.weather.gov