353 FZUS73 KLOT 180204 MWSLOT Marine Weather Statement National Weather Service Chicago/Romeoville 904 PM CDT Fri Apr 17 2026 LMZ740-741-777-779-180300- /O.CON.KLOT.MA.W.0027.000000T0000Z-260418T0300Z/ 904 PM CDT Fri Apr 17 2026 ...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 1000 PM CDT... For the following areas... Nearshore Waters from Winthrop Harbor to Northerly Island... Open Waters from Winthrop Harbor to Michigan City out to Mid Lake... At 904 PM CDT, severe thunderstorms capable of producing waterspouts were located along a line extending from 8 nm east of Winthrop Harbor to near Waukegan Harbor to 6 nm east of Elgin, moving east at 40 knots. HAZARD...Waterspouts and wind gusts in excess of 65 knots. SOURCE...Radar indicated. IMPACT...Waterspouts can easily overturn boats and create locally hazardous seas. Boats could suffer significant structural damage in high winds. Small craft could capsize in suddenly higher waves. Locations impacted include... Harrison-Dever Crib, Wilmette Harbor, Winthrop Harbor, Montrose Harbor, Monroe Harbor, Waukegan Harbor, Belmont Harbor, Diversy Harbor, and DuSable Harbor. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Tornado Watch remains in effect until 1100 PM CDT for northeastern Illinois...and the adjacent waters of Lake Michigan. Move to safe harbor immediately as gusty winds and high waves are expected. Thunderstorms can produce sudden waterspouts. Waterspouts can easily overturn boats and create locally hazardous seas. Seek safe harbor immediately. && LAT...LON 4246 8702 4209 8696 4209 8697 4186 8738 4188 8762 4189 8762 4189 8760 4190 8762 4206 8767 4214 8775 4227 8783 4233 8783 4239 8780 4248 8780 TIME...MOT...LOC 0204Z 262DEG 38KT 4249 8761 4227 8776 4202 8815 WATERSPOUT...POSSIBLE HAIL...0.00IN WIND...65KTS $$ Yack  337 FZUS73 KMKX 180205 MWSMKX Marine Weather Statement National Weather Service Milwaukee/Sullivan WI 905 PM CDT Fri Apr 17 2026 LMZ643-644-669-671-180215- /O.EXP.KMKX.MA.W.0017.000000T0000Z-260418T0215Z/ 905 PM CDT Fri Apr 17 2026 ...THE SPECIAL MARINE WARNING WILL EXPIRE AT 915 PM CDT... The affected areas were... Lake Michigan nearshore and open waters to mid lake from Sheboygan WI to North Port Light WI... The thunderstorms have moved out of the area and no longer pose a significant threat to boaters. A Tornado Watch remains in effect until 1000 PM CDT for southeastern Wisconsin. && LAT...LON 4383 8710 4370 8712 4343 8715 4330 8713 4323 8791 4339 8787 4345 8781 4358 8778 4368 8770 4375 8771 4376 8770 4379 8772 4389 8773 4390 8759 TIME...MOT...LOC 0205Z 235DEG 23KT 4424 8684 4383 8729 $$ WAGNER  888 FZUS73 KMKX 180224 MWSMKX Marine Weather Statement National Weather Service Milwaukee/Sullivan WI 924 PM CDT Fri Apr 17 2026 LMZ644-671-180234- /O.CAN.KMKX.MA.W.0018.000000T0000Z-260418T0245Z/ 924 PM CDT Fri Apr 17 2026 ...THE SPECIAL MARINE WARNING IS CANCELLED... The affected areas were... Nearshore waters from Port Washington WI to North Point Light WI... Lake Michigan from Port Washington WI to North Point Light WI 5 nm off shore to mid lake... The thunderstorms have moved out of the warned area and no longer pose a significant threat to boaters. && LAT...LON 4248 8780 4261 8782 4271 8777 4278 8775 4286 8784 4297 8785 4303 8790 4305 8788 4306 8710 4246 8702 TIME...MOT...LOC 0224Z 242DEG 24KT 4354 8717 4333 8710 4323 8720 $$ LMZ645-646-673-675-180245- /O.CON.KMKX.MA.W.0018.000000T0000Z-260418T0245Z/ 924 PM CDT Fri Apr 17 2026 ...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 945 PM CDT... For the following areas... Lake Michigan nearshore and open waters to mid lake from North Point Light WI to Winthrop Harbor IL... At 924 PM CDT, severe thunderstorms capable of producing waterspouts were located along a line extending from 27 nm east of Oostburg to 29 nm west of White Lake Pier Heads to 30 nm east of Bayside, moving northeast at 25 knots. HAZARD...Waterspouts and wind gusts 34 knots or greater. SOURCE...Radar indicated. IMPACT...Waterspouts can easily overturn boats and create locally hazardous seas. Small craft could be damaged in briefly higher winds and suddenly higher waves. Severe thunderstorms will remain over mainly open waters. PRECAUTIONARY/PREPAREDNESS ACTIONS... Move to safe harbor until hazardous weather passes. && LAT...LON 4248 8780 4261 8782 4271 8777 4278 8775 4286 8784 4297 8785 4303 8790 4305 8788 4306 8710 4246 8702 TIME...MOT...LOC 0224Z 242DEG 24KT 4354 8717 4333 8710 4323 8720 WATERSPOUT...POSSIBLE HAIL...0.00IN WIND...>34KTS $$ WAGNER  985 FZUS73 KLOT 180245 MWSLOT Marine Weather Statement National Weather Service Chicago/Romeoville 945 PM CDT Fri Apr 17 2026 LMZ740-741-777-779-180300- /O.CON.KLOT.MA.W.0027.000000T0000Z-260418T0300Z/ 945 PM CDT Fri Apr 17 2026 ...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 1000 PM CDT... For the following areas... Nearshore Waters from Winthrop Harbor to Northerly Island... Open Waters from Winthrop Harbor to Michigan City out to Mid Lake... At 945 PM CDT, severe thunderstorms capable of producing waterspouts were located along a line extending from 8 nm west of Waukegan Harbor to 11 nm northwest of Wilmette Harbor to near Ohare Airport, moving northeast at 55 knots. HAZARD...Waterspouts and wind gusts to nearly 50 knots. SOURCE...Radar indicated. IMPACT...Waterspouts can easily overturn boats and create locally hazardous seas. Small craft could be damaged in briefly higher winds and suddenly higher waves. Locations impacted include... Harrison-Dever Crib, Wilmette Harbor, Winthrop Harbor, Montrose Harbor, Monroe Harbor, Waukegan Harbor, Belmont Harbor, Diversy Harbor, and DuSable Harbor. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Tornado Watch remains in effect until 1100 PM CDT for northeastern Illinois...and the adjacent waters of Lake Michigan. Move to safe harbor immediately as gusty winds and high waves are expected. Thunderstorms can produce sudden waterspouts. Waterspouts can easily overturn boats and create locally hazardous seas. Seek safe harbor immediately. && LAT...LON 4246 8702 4209 8696 4209 8697 4186 8738 4188 8762 4189 8762 4189 8760 4190 8762 4206 8767 4214 8775 4227 8783 4233 8783 4239 8780 4248 8780 TIME...MOT...LOC 0245Z 240DEG 56KT 4235 8801 4219 8787 4193 8788 WATERSPOUT...POSSIBLE HAIL...0.00IN WIND...49KTS $$ Yack  864 FZUS73 KLOT 180246 MWSLOT Marine Weather Statement National Weather Service Chicago/Romeoville 946 PM CDT Fri Apr 17 2026 LMZ741>745-779-180400- /O.CON.KLOT.MA.W.0028.000000T0000Z-260418T0400Z/ 946 PM CDT Fri Apr 17 2026 ...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT... For the following areas... Nearshore Waters from Wilmette Harbor to Calumet Harbor... Nearshore Waters from Calumet Harbor to Michigan City... Open Waters from Wilmette Harbor to Michigan City out to Mid Lake... At 946 PM CDT, severe thunderstorms capable of producing waterspouts were located along a line extending from 9 nm northwest of Ohare Airport to 6 nm west of Midway Airport to 11 nm south of Joliet, moving east at 35 knots. HAZARD...Waterspouts and wind gusts to nearly 50 knots. SOURCE...Radar indicated. IMPACT...Waterspouts can easily overturn boats and create locally hazardous seas. Small craft could be damaged in briefly higher winds and suddenly higher waves. Locations impacted include... Calumet Harbor, Indiana Harbor, 31st Street Harbor, Monroe Harbor, Burns Harbor, Marina Shores at Dune Harbor, Burnham Harbor, 59th Street Marina, Hammond Marina, Jackson Park Harbor, and DuSable Harbor. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Tornado Watch remains in effect until 1100 PM CDT for northeastern Illinois...northwestern Indiana...and the adjacent waters of Lake Michigan. Move to safe harbor immediately as gusty winds and high waves are expected. Thunderstorms can produce sudden waterspouts. Waterspouts can easily overturn boats and create locally hazardous seas. Seek safe harbor immediately. && LAT...LON 4162 8733 4164 8743 4168 8743 4167 8744 4169 8750 4175 8753 4179 8758 4178 8758 4188 8762 4211 8696 4179 8697 4179 8696 4172 8691 4166 8709 4165 8714 4163 8716 4162 8732 4161 8732 TIME...MOT...LOC 0246Z 274DEG 35KT 4210 8802 4179 8788 4134 8807 WATERSPOUT...POSSIBLE HAIL...0.00IN WIND...49KTS $$ Yack  681 FZUS73 KGRR 180248 MWSGRR Marine Weather Statement National Weather Service Grand Rapids MI 1048 PM EDT Fri Apr 17 2026 LMZ844>847-872-874-876-878-180445- /O.CON.KGRR.MA.W.0019.000000T0000Z-260418T0445Z/ 1048 PM EDT Fri Apr 17 2026 ...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 1245 AM EDT... For the following areas... Nearshore and Open Waters from St Joseph to Whitehall MI... At 1048 PM EDT, strong thunderstorms were located along a line extending from 8 nm west of White Lake Pier Heads to 24 nm east of Winthrop Harbor to 19 nm northwest of New Buffalo, moving northeast at 35 knots. HAZARD...Wind gusts to 40 knots and small hail. SOURCE...Radar indicated. IMPACT...Small craft could be damaged in briefly higher winds and suddenly higher waves. Locations impacted include... South Haven Light, St. Joseph Light, White Lake Pier Heads, Mona Lake Channel, Holland Light, The White Lake Pierheads, Muskegon Light, and St. Joseph. PRECAUTIONARY/PREPAREDNESS ACTIONS... Move to safe harbor until hazardous weather passes. && LAT...LON 4213 8656 4212 8696 4337 8714 4340 8643 4312 8627 4277 8621 4248 8625 4225 8635 4211 8649 TIME...MOT...LOC 0248Z 225DEG 34KT 4342 8661 4250 8724 4205 8699 HAIL...<.75IN WIND...40KTS $$ OSTUNO