289 FLUS43 KMKX 291138 HWOMKX Hazardous Weather Outlook National Weather Service Milwaukee/Sullivan WI 638 AM CDT Mon Jun 29 2026 WIZ046-047-051-052-056>060-062>072-301145- Marquette-Green Lake-Fond du Lac-Sheboygan-Sauk-Columbia-Dodge- Washington-Ozaukee-Iowa-Dane-Jefferson-Waukesha-Milwaukee- Lafayette-Green-Rock-Walworth-Racine-Kenosha- 638 AM CDT Mon Jun 29 2026 This Hazardous Weather Outlook is for portions of east central Wisconsin, south central Wisconsin and southeast Wisconsin. .DAY ONE...Today and Tonight An Extreme Heat Warning is in effect starting at noon today and continuing throughout tonight for daytime heat index values up to 108 degrees and overnight index values in the upper 70s. High swim risk conditions through this evening for the Lake Michigan beaches in Sheboygan and Ozaukee Counties with moderate swim risk conditions in Milwaukee and Racine Counties. Chances for isolated storm development tonight toward central Wisconsin, with only slight chances from Madison to Milwaukee. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Hot and humid conditions with daily maximum heat index values of 95 to 108 degrees for much of the week. An Extreme Heat Warning is in effect for Tuesday, but additional heat headlines will likely be needed later in the week. Increasing chances for thunderstorms Tuesday night through the end of the week. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed. $$ LMZ643>646-301145- Sheboygan to Port Washington WI- Port Washington to North Point Light WI- North Point Light to Wind Point WI- Wind Point WI to Winthrop Harbor IL- 638 AM CDT Mon Jun 29 2026 This Hazardous Weather Outlook is for the nearshore waters from Sheboygan Wisconsin to Winthrop Harbor Illinois. .DAY ONE...Today and Tonight A Small Craft Advisory is in effect through this evening for gusty south winds and building waves. Isolated thunderstorms possible tonight. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Daily chances for thunderstorms Tuesday night through the end of the week, with better chances to the north of North Point Lighthouse. $$ LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868- 870-872-874-876-878-301145- Lake Michigan Michigan City IN to St. Joseph MI 5 NM offshore to mid-line of lake.- Lake Michigan from Seul Choix Point to Rock Island Passage 5NM 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 5NM offshore- Lake Michigan from Charlevoix to Point Betsie MI 5NM Offshore to mid lake- Lake Michigan from Point Betsie to Manistee MI 5NM offshore to Mid Lake- Lake Michigan from Rock Island Passage to Sturgeon Bay WI 5NM offshore to mid lake- Lake Michigan from Sturgeon Bay to Two Rivers WI 5NM offshore to Mid Lake- Lake Michigan from Two Rivers to Sheboygan WI 5NM offshore to Mid Lake- Lake Michigan from Sheboygan to Port Washington WI 5NM offshore to Mid Lake- Lake Michigan from Port Washington to North Point Light WI 5NM offshore to Mid Lake- Lake Michigan from North Point Light to Wind Point WI 5NM offshore to Mid Lake- Lake Michigan from Wind Point WI to Winthrop Harbor IL 5NM offshore to Mid Lake- Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5NM offshore to Mid Lake- Lake Michigan from Wilmette Harbor to Michigan City in 5NM offshore to Mid Lake- Lake Michigan from Pentwater to Manistee MI 5NM offshore to Mid Lake- Lake Michigan from Whitehall to Pentwater MI 5NM offshore to Mid Lake- Lake Michigan from Grand Haven to Whitehall MI 5NM offshore to Mid Lake- Lake Michigan from Holland to Grand Haven MI 5NM offshore to Mid Lake- Lake Michigan from South Haven to Holland MI 5NM offshore to Mid lake- Lake Michigan from St Joseph to South Haven MI 5NM offshore to Mid Lake- 638 AM CDT Mon Jun 29 2026 This Hazardous Weather Outlook is for the open waters of Lake Michigan. .DAY ONE...Today and Tonight Expect scattered thunderstorms across the northern two thirds this morning and again tonight. Dense fog may develop tonight as a warm and humid airmass moves over the cooler waters. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Areas of dense fog may occur at times due to a very warm and humid airmass over the colder waters of Lake Michigan. Daily chances for thunderstorms Tuesday through the end of the week. $$ www.weather.gov/mkx