Hazardous Weather Outlook
Issued by NWS Chicago, IL

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FLUS43 KLOT 211749
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
1249 PM CDT Fri Jul 21 2017

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
221800-
Winnebago-Boone-McHenry-Lake Illinois-Ogle-Lee-De Kalb-Kane-
DuPage-Cook-La Salle-Kendall-Grundy-Will-Kankakee-Livingston-
Iroquois-Ford-Lake Indiana-Porter-Newton-Jasper-Benton-
1249 PM CDT Fri Jul 21 2017 /149 PM EDT Fri Jul 21 2017/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS...
NORTHEAST ILLINOIS AND NORTHWEST INDIANA.

.DAY ONE...This Afternoon and Tonight.

WEATHER HAZARDS EXPECTED:
  Significant Thunderstorm Risk...with an associated:
      Significant Thunderstorm Wind Damage Risk...up to 70 mph.
      Elevated Hail Risk...up to quarter size.
      Limited Tornado Risk.
  Significant Flooding Risk.
  Significant Excessive Heat Risk this afternoon.

DISCUSSION:

Thunderstorm potential will increase late this afternoon through
early Saturday morning, with the potential to produce torrential rainfall
and flash flooding. Strong to severe storms will be most likely
from late this afternoon through this evening, with damaging winds
the primary severe weather threat, in addition to very heavy rainfall.
Behind the initial line of storms, additional heavy rain producing
thunderstorms will likely develop for some areas.
Heaviest rainfall amounts, in excess of 1.5 inches or more, are expected to
occur primarily over far northern Illinois north of Interstate 80.

Heat index readings will approach 105 degrees both today and
Saturday, mainly along and south of Interstate 80.

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

Saturday...
  Limited Flooding Risk.
  Elevated Severe Thunderstorm Risk.
  Elevated Excessive Heat Risk.
Sunday...
  Limited Severe Thunderstorm Risk.
Thursday...
  Limited Thunderstorm Risk.

In addition, flooding will continue along portions of the Fox and
Des Plaines Rivers.

.SPOTTER INFORMATION STATEMENT...

Spotters will likely be needed beginning this evening.

GENERAL STORM MOTION OF THE DAY:

Toward the east-southeast at 35 to 40 mph.

&&

$$

LMZ740>745-221800-
Winthrop Harbor to Wilmette Harbor-
Wilmette Harbor to Northerly Island-
Northerly Island to Calumet Harbor-Calumet Harbor to Gary-
Gary to Burns Harbor-Burns Harbor to Michigan City-
1249 PM CDT Fri Jul 21 2017

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS NEARSHORE
WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE WATERS OF LAKE
MICHIGAN.

.DAY ONE...This Afternoon and Tonight.

  Significant Thunderstorm Risk.

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

Saturday and Sunday...
  Limited Thunderstorm Risk.
Monday...
  Hazardous Conditions for Small Craft are likely.
Thursday...
  Limited Thunderstorm Risk.

&&

$$

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-221800-
Lake Michigan from Michigan City IN to St. Joseph MI 5 NM
offshore to Mid Lake-
Lake Michigan from Seul Choix Point to Rock Island Passage 5 NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and north of a line from Charlevoix MI to South
Fox Island 5 NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5 NM offshore to
Mid Lake-
Lake Michigan from Point Betsie to Manistee MI 5 NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5 NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5 NM offshore to
Mid Lake-
Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5 NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5 NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM
offshore to Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5 NM offshore to Mid
Lake-
Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid
Lake-
Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to
Mid Lake-
1249 PM CDT Fri Jul 21 2017

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE OPEN WATERS OF LAKE
MICHIGAN.

.DAY ONE...This Afternoon and Tonight.

Thunderstorms are likely across the southern half of the lake
this evening and overnight. Winds in excess of 30 kt are probable
this evening for this same area.

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

Low chances of thunderstorms exist for the weekend.

&&

$$

KMD

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