351 

FLUS43 KLOT 290815

HWOLOT



Hazardous Weather Outlook

National Weather Service Chicago/Romeoville IL

315 AM CDT Mon Jun 29 2026



ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-

010-011-019-300815-

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-

315 AM CDT Mon Jun 29 2026 /415 AM EDT Mon Jun 29 2026/



This Hazardous Weather Outlook is for portions of north central

Illinois...northeast Illinois and northwest Indiana.



.DAY ONE...Today and Tonight.



Weather hazards expected...



  Elevated Excessive Heat Risk.



DISCUSSION...



Dangerous heat with afternoon heat index values over 100 degrees

is expected today. Heat index values will remain above 75 in most

areas tonight, offering little relief from the heat. 



.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.



Tuesday and Wednesday...

  Elevated Excessive Heat Risk.

Thursday...

  Limited Flooding Risk.

  Limited Thunderstorm Risk.

  Elevated Excessive Heat Risk.

Friday...

  Limited Flooding Risk.

  Limited Thunderstorm Risk.

Saturday and Sunday...

  Limited Thunderstorm Risk.



DISCUSSION...



Dangerous heat with afternoon heat index values over 100 degrees 

is expected to persist through at least Wednesday. Depending on 

potential thunderstorm coverage late in the week, the dangerous 

heat may persist into the weekend. It does appear that a more 

active pattern will return by the weekend, with a return of 

more frequent thunderstorm chances. 



.SPOTTER INFORMATION STATEMENT...



  Spotter activation will not be necessary through tonight.



$$



LMZ740>745-300815-

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-

315 AM CDT Mon Jun 29 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...Today and Tonight.



  Hazardous conditions for small craft are likely.



.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.



Tuesday...

  Hazardous conditions for small craft are likely.

Thursday through Sunday...

  Limited Thunderstorm Risk.



$$



Ratzer



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