Hazard Report Provided By forecast.weather.gov

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
222 PM CDT Tue Jun 30 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-011930-
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-
222 PM CDT Tue Jun 30 2026 /322 PM EDT Tue Jun 30 2026/

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

.DAY ONE...Tonight.

Weather hazards expected...

  Elevated Excessive Heat Risk.

DISCUSSION...

Oppressive heat will continue through midnight especially in the
city of Chicago where heat indices are not expected to fall below
90 degrees until after midnight.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Wednesday and Thursday...
  Elevated Excessive Heat Risk.
Thursday Night...
  Limited Flooding Risk.
  Limited Thunderstorm Risk...with an associated:
     Level 1 of 5 Severe Thunderstorm Risk.
Friday...
  Limited Flooding Risk.
  Limited Thunderstorm Risk.
  Limited Excessive Heat Risk.
Saturday...
  Limited Flooding Risk.
  Limited Thunderstorm Risk.
Sunday and Monday...
  Limited Thunderstorm Risk.

DISCUSSION...

Dangerous heat will likely persist into Thursday across much of
the area. Thunderstorm chances will increase late Thursday and
continue at times through the holiday weekend. Some storms may be
severe and produce locally heavy rainfall.

.SPOTTER INFORMATION STATEMENT...

  Spotter activation will not be necessary through tonight.

$$

URGENT - WEATHER MESSAGE
National Weather Service Chicago IL
840 PM CDT Tue Jun 30 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-106>108-INZ001-002-
010-011-019-011145-
/O.CON.KLOT.XH.W.0001.000000T0000Z-260703T0500Z/
Winnebago-Boone-McHenry-Lake IL-Ogle-Lee-De Kalb-Kane-DuPage-La
Salle-Kendall-Grundy-Kankakee-Livingston-Iroquois-Ford-Northern
Will-Southern Will-Eastern Will-Lake IN-Porter-Newton-Jasper-
Benton-
Including the cities of Byron, Ottawa, Oxford, Woodstock,
Waukegan, DeMotte, Yorkville, Elgin, Coal City, Bolingbrook,
Rensselaer, Oswego, Buffalo Grove, Algonquin, Wheaton, Mundelein,
Plano, Morocco, Carol Stream, Oregon, Marseilles, Gilman, Joliet,
Rockford, Mokena, Fairbury, Channahon, Paxton, Lombard, Dixon,
Beecher, Mendota, La Salle, McHenry, Bradley, Plainfield,
Hammond, Portage, Streator, Morris, Valparaiso, Watseka, Downers
Grove, Kankakee, Gibson City, Naperville, Manhattan, Minooka,
Rochelle, Dwight, Chesterton, Pontiac, Roselawn, Sycamore,
Wilmington, Peotone, Gary, Fowler, Belvidere, Crystal Lake,
Bourbonnais, Crete, Aurora, Merrillville, DeKalb, Gurnee, and
Kentland
840 PM CDT Tue Jun 30 2026 /940 PM EDT Tue Jun 30 2026/

...EXTREME HEAT WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CDT /1 AM
EDT/ THURSDAY NIGHT...

* WHAT...Dangerously hot conditions with heat index values around
  105 expected each afternoon.

* WHERE...Northern and central Illinois and northwest Indiana.

* WHEN...Until midnight CDT /1 AM EDT/ Thursday Night.

* IMPACTS...Heat related illnesses increase significantly during
  extreme heat and high humidity events.

* ADDITIONAL DETAILS...Dangerous heat is expected to persist through
  Thursday. Thunderstorms may begin to bring some relief from the
  heat for portions of northern Illinois by Thursday afternoon or
  evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors.

Do not leave young children and pets in unattended vehicles. Car
interiors will reach lethal temperatures in a matter of minutes.

&&

$$

Hazard Report Provided By forecast.weather.gov