Heat Advisory for McHenry Co., IL until 10:00 PM CDT 7/23

C: Mchenrycountywx | L: Woodstock | PL: McHenry County WX

WWUS73 KLOT 231531
NPWLOT

URGENT - WEATHER MESSAGE
National Weather Service Chicago IL
1031 AM CDT Wed Jul 23 2025


/O.CON.KLOT.HT.Y.0002.000000T0000Z-250724T0300Z/
Winnebago-Boone-McHenry-Ogle-Lee-De Kalb-
Including the cities of Rockford, DeKalb, Woodstock, Sycamore,
Crystal Lake, McHenry, Byron, Algonquin, Oregon, Rochelle, Dixon,
and Belvidere
1031 AM CDT Wed Jul 23 2025

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 10 PM CDT THIS EVENING...

* WHAT...Peak afternoon heat index values of 105 to 108 expected.

* WHERE...Boone, De Kalb, Lee, Ogle, Winnebago, and McHenry Counties.

* WHEN...Until 10 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat
illnesses.

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.

&&


https://wxn.io/nfqx1

Hazardous Weather Outlook for McHenry Co., IL

C: Mchenrycountywx | L: Woodstock | PL: McHenry County WX

FLUS43 KLOT 231323 AAA
HWOLOT

Hazardous Weather Outlook...UPDATED
National Weather Service Chicago/Romeoville IL
823 AM CDT Wed Jul 23 2025


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-
823 AM CDT Wed Jul 23 2025 /923 AM EDT Wed Jul 23 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...

Limited Thunderstorm Risk.
Significant Excessive Heat Risk.

DISCUSSION...

A few isolated thunderstorms may develop this afternoon.

Peak afternoon heat index values of 100 to 110 degrees are
expected this afternoon.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

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

DISCUSSION...

Peak afternoon heat index values of 100 to 110 degrees are
expected again Thursday afternoon.

The chance of thunderstorms will increase late Thursday afternoon
near the Wisconsin border, with thunderstorm chances gradually
spreading south across the remainder of northern Illinois
Thursday evening. Any thunderstorms that do occur will be capable
of producing torrential rainfall and localized flash flooding
with a slight chance of locally damaging winds.

Periodic thunderstorms Friday through Saturday will bring the
chance for torrential rainfall and localized flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be necessary through tonight.

GENER...

https://wxn.io/m8jm5

Hazardous Weather Outlook for McHenry Co., IL

C: Mchenrycountywx | L: Woodstock | PL: McHenry County WX

FLUS43 KLOT 230909
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
409 AM CDT Wed Jul 23 2025


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-
409 AM CDT Wed Jul 23 2025 /509 AM EDT Wed Jul 23 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...

Significant Excessive Heat Risk.
Limited Thunderstorm Risk.

DISCUSSION...

There is a 20 percent chance of isolated thunderstorms early this
morning over northwest Illinois. A few additional isolated
thunderstorms may develop across parts of northern Illinois this
afternoon.

Dangerous heat and humidity with peak afternoon heat index values
of 100 to 110 degrees are expected this afternoon.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

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


DISCUSSION...

Dangerous heat and humidity with peak afternoon heat index values
of 100 to 110 degrees are expected again Thursday.

The chance of thunderstorms will increase late Thursday afternoon
near the Wisconsin border, with thunderstorm chances gradually
spreading south across the remainder of northern Illinois
Thursday evening. Any thunderstorms that do occur will be capable
of producing torrential rainfall and localized flash flooding
with a slight chance of locally damaging winds.

Periodic thunderstorms Fr...

https://wxn.io/oclp3

Heat Advisory for McHenry Co., IL until 10:00 PM CDT 7/23

C: Mchenrycountywx | L: Woodstock | PL: McHenry County WX

WWUS73 KLOT 230846
NPWLOT

URGENT - WEATHER MESSAGE
National Weather Service Chicago IL
346 AM CDT Wed Jul 23 2025


/O.CON.KLOT.HT.Y.0002.250723T1500Z-250724T0300Z/
Winnebago-Boone-McHenry-Ogle-Lee-De Kalb-
Including the cities of Algonquin, Rockford, Belvidere, Sycamore,
Woodstock, Crystal Lake, McHenry, Dixon, Byron, DeKalb, Rochelle,
and Oregon
346 AM CDT Wed Jul 23 2025

...HEAT ADVISORY REMAINS IN EFFECT FROM 10 AM THIS MORNING TO 10 PM
CDT THIS EVENING...

* WHAT...Peak afternoon heat index values of 105 to 108 expected.

* WHERE...Boone, De Kalb, Lee, Ogle, Winnebago, and McHenry Counties.

* WHEN...From 10 AM this morning to 10 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat
illnesses.

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.

&&


https://wxn.io/fkjzg

Hazardous Weather Outlook for McHenry Co., IL

C: Mchenrycountywx | L: Woodstock | PL: McHenry County WX

FLUS43 KLOT 230158
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
858 PM CDT Tue Jul 22 2025


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-
858 PM CDT Tue Jul 22 2025 /958 PM EDT Tue Jul 22 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 northwest Illinois.

DISCUSSION...

There is a slight chance of a thunderstorm toward sunrise over
northwest Illinois.

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

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

DISCUSSION...

Dangerous heat and humidity with peak afternoon heat index values
of 100 to 110 degrees are expected Wednesday and Thursday.

There is a slight chance of a thunderstorm in the Rockford
vicinity early Wednesday morning.

The chance of thunderstorms will increase late Thursday afternoon
near the Wisconsin border, with thunderstorm chances gradually
spreading south across the remainder of northern Illinois Thursday
evening. Any thunderstorms that do occur will be capable of
producing torrential rainfall and localized flash flooding with a
slight chance of locally damaging winds.

While there will be many dry hours, there will be periodic
chances of thunderstorms Friday through Monday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be nece...

https://wxn.io/xh3b9

Heat Advisory for McHenry Co., IL until 10:00 PM CDT 7/23

C: Mchenrycountywx | L: Woodstock | PL: McHenry County WX

WWUS73 KLOT 230153
NPWLOT

URGENT - WEATHER MESSAGE
National Weather Service Chicago IL
853 PM CDT Tue Jul 22 2025


/O.CON.KLOT.HT.Y.0002.250723T1500Z-250724T0300Z/
Winnebago-Boone-McHenry-Ogle-Lee-De Kalb-
Including the cities of Crystal Lake, Woodstock, Rochelle,
DeKalb, Oregon, Rockford, McHenry, Algonquin, Belvidere, Byron,
Sycamore, and Dixon
853 PM CDT Tue Jul 22 2025

...HEAT ADVISORY REMAINS IN EFFECT FROM 10 AM TO 10 PM CDT
WEDNESDAY...

* WHAT...Peak afternoon heat index values of 100 to 108 expected.

* WHERE...Boone, De Kalb, Lee, Ogle, Winnebago, and McHenry Counties.

* WHEN...From 10 AM to 10 PM CDT Wednesday.

* IMPACTS...Hot temperatures and high humidity may cause heat
illnesses.

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.

&&


https://wxn.io/b5drp

Hazardous Weather Outlook for McHenry Co., IL

C: Mchenrycountywx | L: Woodstock | PL: McHenry County WX

FLUS43 KLOT 222008
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
308 PM CDT Tue Jul 22 2025


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-
308 PM CDT Tue Jul 22 2025 /408 PM EDT Tue Jul 22 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.

DISCUSSION...

There is a slight chance of a thunderstorm toward sunrise over
north central Illinois.

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

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

DISCUSSION...

Dangerous heat and humidity with peak afternoon heat index values
of 100 to 110 degrees are expected Wednesday and Thursday.

There is a slight chance of a thunderstorm in the Rockford
vicinity early Wednesday morning.

The chance of thunderstorms will increase late Thursday afternoon
near the Wisconsin border, with thunderstorm chances gradually
spreading south across the remainder of northern Illinois Thursday
evening. Any thunderstorms that do occur will be capable of
producing torrential rainfall and localized flash flooding with a
slight chance of locally damaging winds.

While there will be many dry hours, there will be periodic
chances of thunderstorms Friday through Monday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be necessary through tonig...

https://wxn.io/7ro6r