Special Marine Warning Issued for Lake Michigan Near Chicago
This alert is no longer in effect.
NOAA issued it on August 11, 2026, 12 days 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 for nearshore and open waters of Lake Michigan from Winthrop Harbor to Michigan City until 12:15 PM CDT due to severe thunderstorms.
Read this weather record in 30 seconds
- Record type
- Special Marine Warning
- Affected area
- Lake Michigan near Chicago IL and Northwest Indiana
- Issued
- August 11, 2026
- Issuing authority
- NWS Chicago IL
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 12 days ago; use the issuing agency's live warning service for current conditions in Lake Michigan near Chicago IL and Northwest Indiana.
Alert Details
Special Marine Warning issued by NWS Chicago IL. Effective from 10:09 AM CDT August 11, 2026, until 12:15 PM CDT August 11, 2026. Severity: Severe. Urgency: Immediate. Certainty: Likely.
Affected Areas
Nearshore Waters from Winthrop Harbor to Calumet Harbor IL; Nearshore Waters from Calumet Harbor to Michigan City IN; Open Waters from Winthrop Harbor to Michigan City out to Mid Lake. Specific locations include Montrose Harbor, Wilmette Harbor, Belmont Harbor, Diversey Harbor, Monroe Harbor, 31st Street Harbor, Harrison-Dever Crib, Burnham Harbor, Jackson Park Harbor, 59th Street Marina, DuSable Harbor, Calumet Harbor, Hammond Marina, Indiana Harbor, Marina Shores at Dune Harbor, Burns Harbor, and Michigan City.
What You Should Do
Avoid the warned waters. Boats could suffer significant structural damage in high winds and small craft could capsize in suddenly higher waves.
Expected Conditions
Severe thunderstorms with wind gusts in excess of 50 knots. Storms moving east at 40 knots.
Timeline
Alert in effect from 10:09 AM CDT until 12:15 PM CDT on August 11, 2026.
Original source: NOAA Official Notice ↗
Related Weather Alerts
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Two Areazine-derived peer sets for this NWS weather alert: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.
Similar body length
Nearest notices by article body length (1,110 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to August 11, 2026.
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