Special Marine Warning Issued for Southern Lake Michigan Harbors and Open Waters
This alert is no longer in effect.
NOAA issued it on April 6, 2026, 4 months ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).
Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.
NWS Chicago has issued a Special Marine Warning until 7:45 PM CDT for Lake Michigan waters from Wilmette Harbor to Michigan City due to a severe thunderstorm with 34-knot winds and large hail.
Read this weather record in 30 seconds
- Record type
- Special Marine Warning
- Affected area
- Southern Lake Michigan
- Issued
- April 6, 2026
- Issuing authority
- NWS Chicago
Marine notices apply to named waters or shoreline zones. They may not describe conditions on land, even when the nearest place name is the same.
Record status: historical. It was issued 4 months ago; use the issuing agency's live warning service for current conditions in Southern Lake Michigan.
Alert Details
The National Weather Service in Chicago has issued a Special Marine Warning for the nearshore and open waters of Lake Michigan. The alert was issued at 5:45 PM CDT on March 10, 2026, following reports from law enforcement regarding a severe thunderstorm moving through the region.
Affected Areas
The warning affects the following geographic regions and maritime zones:
- Nearshore Waters: Wilmette Harbor to Calumet Harbor, and Calumet Harbor to Michigan City.
- Open Waters: Winthrop Harbor to Michigan City, extending from 5 nautical miles offshore to Mid Lake.
Specific locations impacted include Harrison-Dever Crib, 31st Street Harbor, Monroe Harbor, Burns Harbor, Calumet Harbor, Indiana Harbor, Montrose Harbor, Burnham Harbor, Hammond Marina, Jackson Park Harbor, Belmont Harbor, and Marina Shores at Dune Harbor.
What You Should Do
Mariners are advised to move to safe harbor immediately. Remain in port until the hazardous weather conditions have passed. Small craft should be especially cautious as they could be damaged by suddenly higher winds and waves.
Expected Conditions
At 5:45 PM CDT, a severe thunderstorm was tracked 10 nautical miles west of Midway Airport (approximately 17 nm west of 31st Street Harbor), moving northeast at 25 knots.
- Hazards: Wind gusts of 34 knots or greater and large hail.
- Impacts: Potential for structural damage from hail and damage to small craft from elevated wind and wave activity.
Timeline
The Special Marine Warning is effective immediately and is currently set to expire at 7:45 PM CDT on March 10, 2026.
Original source: NOAA Official Notice ↗
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