754
FLUS43 KLOT 212027
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
327 PM CDT Fri Aug 21 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-222030-
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-
327 PM CDT Fri Aug 21 2026 /427 PM EDT Fri Aug 21 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 1 of 5 Tornado Risk.
     Level 2 of 5 Damaging Wind Risk...up to 60 mph.
     Level 2 of 5 Large Hail Risk...up to golf ball size.
  Limited Flooding Risk.

DISCUSSION...

Scattered thunderstorms are expected through this evening. The
primary threats will be large hail and damaging winds. An
isolated tornado will also be possible.

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

Saturday...
  Limited Thunderstorm Risk.
  High Swim Risk Lake Michigan Beaches in Porter County.
Sunday...
  High Swim Risk Lake Michigan Beaches.
Tuesday through Thursday...
  Limited Thunderstorm Risk.

DISCUSSION...

Isolated thunderstorms are possible Saturday. Severe weather is
not expected.

High waves will create dangerous swimming conditions at Lake
Michigan beaches in Porter County Indiana Saturday and possibly
at all Lake Michigan beaches Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotters may be needed through this evening.

GENERAL STORM MOTION OF THE DAY:

Moving toward the southeast at 20 to 30 mph.

$$

LMZ740>745-222030-
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-
327 PM CDT Fri Aug 21 2026

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.

Weather hazards expected...

  Elevated Thunderstorm Risk...with an associated:
     Level 2 of 5 Thunderstorm Wind Gust Risk...up to 50 knots.
     Level 2 of 5 Hail Risk...up to half dollar size.

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

Saturday...
  Limited Thunderstorm Risk.
Sunday...
  Hazardous conditions for small craft are likely.
Tuesday through Thursday...
  Limited Thunderstorm Risk.

$$

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