Hazardous Weather Outlook
Issued by NWS Chicago, IL

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FLUS43 KLOT 182013
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
313 PM CDT Fri Jul 18 2025

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-192015-
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-
313 PM CDT Fri Jul 18 2025 /413 PM EDT Fri Jul 18 2025/

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 Late Tonight.

DISCUSSION...

A line of decaying thunderstorms may bring gusty winds to
northern Illinois west of the Chicago metro toward sunrise
Saturday morning.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Saturday...
  Elevated Thunderstorm Risk...with an associated:
     Level 2 of 5 Severe Thunderstorm Risk.
  Elevated Flooding Risk.
Sunday...
  Limited Thunderstorm Risk...with an associated:
     Level 1 of 5 Severe Thunderstorm Risk south of I-80.
  Elevated Flooding Risk south of Dixon to Watseka line.
Monday...
  Limited Flooding Risk.
  Limited Thunderstorm Risk.
Tuesday...
  Limited Flooding Risk.
  Limited Thunderstorm Risk.
  Limited Excessive Heat Risk.
Wednesday and Thursday...
  Limited Thunderstorm Risk.
  Elevated Excessive Heat Risk.

DISCUSSION...

Several rounds of thunderstorms may occur through early next
week with strong to severe thunderstorms possible along with
torrential rain and localized flash flooding. The greatest
chances will remain south of I-80.

Dangerous heat and humidity is possible the middle of next week.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be necessary through tonight.

GENERAL STORM MOTION OF THE DAY:

Moving toward the southeast at 30 mph.

$$

LMZ740>745-192015-
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
313 PM CDT Fri Jul 18 2025

This Hazardous Weather Outlook is for portions of the Illinois
nearshore waters of Lake Michigan and the Indiana nearshore
waters of Lake Michigan.

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Saturday...
  Limited Thunderstorm Risk...with an associated:
     Level 2 of 5 Severe Thunderstorm Risk.
Sunday...
  Limited Thunderstorm Risk.
Tuesday through Thursday...
  Limited Thunderstorm Risk.

$$

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