Hazard Report Provided By forecast.weather.gov

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
256 PM CDT Thu Aug 13 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-142100-
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-
256 PM CDT Thu Aug 13 2026 /356 PM EDT Thu Aug 13 2026/

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

.DAY ONE...Tonight.

Weather hazards expected...

  Elevated Thunderstorm Risk...with an associated:
     Level 2 of 5 Damaging Wind Risk...up to 60 mph.
     Level 2 of 5 Large Hail Risk...up to quarter size.
  Elevated Flooding Risk.

DISCUSSION...

Showers are likely tonight with a chance for thunderstorms.
Some of these storms could be severe with primarily a damaging wind
threat mainly south of a Mendota to Rensselaer line.

In addition, locally heavy rainfall due to training storms
may lead to flooding . At this time, the heaviest rainfall is
expected to occur generally south of a Forreston Illinois to
Valparaiso Indiana line.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Friday...
  Significant Flooding Risk.
  Limited Thunderstorm Risk...with an associated:
     Level 1 of 5 Severe Thunderstorm Risk.
Saturday...
  Elevated Flooding Risk.
  Limited Thunderstorm Risk...with an associated:
     Level 1 of 5 Severe Thunderstorm Risk.
Sunday...
  Limited Thunderstorm Risk.
Tuesday night and Wednesday...
  Limited Thunderstorm Risk.

DISCUSSION...

An active weather pattern is expected to persist into this
weekend, with periodic shower and thunderstorm chances. These
showers and storms will be capable of producing torrential
rainfall at times, which could lead to flash flooding.

.SPOTTER INFORMATION STATEMENT...

  Spotters may not be needed, but any reports are appreciated.

GENERAL STORM MOTION OF THE DAY:

  Moving toward the southeast at 25 to 35 mph.

$$

Flood Watch
National Weather Service Chicago IL
208 AM CDT Thu Aug 13 2026

ILZ008-010-011-019>021-023-032-033-039-106>108-INZ010-011-019-131515-
/O.NEW.KLOT.FA.A.0012.260814T0000Z-260814T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ogle-Lee-De Kalb-La Salle-Kendall-Grundy-Kankakee-Livingston-
Iroquois-Ford-Northern Will-Southern Will-Eastern Will-Newton-
Jasper-Benton-
Including the cities of Rochelle, Mokena, Channahon, Watseka, Crete,
Pontiac, Dwight, Byron, Morocco, Oswego, Oxford, Fairbury, Streator,
Beecher, Yorkville, Fowler, Peotone, La Salle, Bradley, Minooka,
Manhattan, Bourbonnais, Marseilles, Sycamore, Bolingbrook, Dixon,
Mendota, Kankakee, Plainfield, Rensselaer, DeMotte, Ottawa, Gilman,
Joliet, Kentland, Oregon, Gibson City, DeKalb, Morris, Plano,
Wilmington, Roselawn, Coal City, and Paxton
208 AM CDT Thu Aug 13 2026 /308 AM EDT Thu Aug 13 2026/

...FLOOD WATCH IN EFFECT FROM THIS EVENING THROUGH FRIDAY MORNING...

* WHAT...Flash flooding caused by excessive rainfall is possible.

* WHERE...Portions of Illinois, including the following areas, De
  Kalb, Eastern Will, Ford, Grundy, Iroquois, Kankakee, Kendall, La
  Salle, Lee, Livingston, Northern Will, Ogle and Southern Will and
  northwest Indiana, including the following areas, Benton, Jasper
  and Newton.

* WHEN...From this evening through Friday morning.

* IMPACTS...Creeks and streams may rise out of their banks.

* ADDITIONAL DETAILS...
  - The potential exists for repeated rounds of showers and
    thunderstorms developing north of a stalled surface front.
    Localized rainfall rates may exceed 2 inches per hour over
    portions of northern Illinois and northwest Indiana tonight into
    early Friday morning. Portions of the watch area received as much
    as 2 to 4 inches of rainfall over the past few days and will be
    more susceptible to flooding with any additional heavy rainfall.
  - http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch for flash flooding means rapid-onset flooding is
possible, but not yet certain, based upon the latest forecasts. Flash
flooding is a dangerous situation. Persons with interests along area
rivers, creeks, and other waterways should monitor the latest
forecasts and be prepared to take action should flooding develop.

&&

$$

Ratzer

Hazard Report Provided By forecast.weather.gov