143
FLUS43 KLOT 210835
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
335 AM CDT Thu Aug 21 2025

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-220845-
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-
335 AM CDT Thu Aug 21 2025 /435 AM EDT Thu Aug 21 2025/

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

.DAY ONE...Today and Tonight.

Weather hazards expected...

  High Swim Risk Lake Michigan Beaches.
  Limited Fog Risk late tonight.

DISCUSSION...

Dangerous swimming conditions will continue at area beaches
through midday today.

Patchy dense fog may impact travel well outside of Chicago late
tonight into early Friday morning.

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

Late Friday Night and Saturday...
  Very Limited Thunderstorm Risk.

DISCUSSION...

An isolated thunderstorm or two is possible after midnight Friday
night across portions of far northern Illinois and then southeast
of I-55 early to mid Saturday afternoon.

.SPOTTER INFORMATION STATEMENT...

  Spotter activation will not be necessary through tonight.

$$

LMZ740>745-220845-
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-
335 AM CDT Thu Aug 21 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...Today and Tonight.

  No hazardous weather is expected at this time.

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

Late Friday Night and Saturday...
  Limited Thunderstorm Risk.

$$

Castro

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