Duluth, MN – Dangerous marine conditions are expected to persist on Lake Superior for several days, with repeated rounds of gale-force winds and the threat of heavy freezing spray impacting the North Shore and open waters.
According to the National Weather Service in Duluth, multiple rounds of gales—with wind gusts exceeding 34 knots—are forecast, especially along the North Shore each night. Conditions are expected to worsen Wednesday night into Thursday, when widespread gales are possible across much of the lake.
Forecasters warn that storm-force wind gusts up to 50 knots are possible near Grand Marais on Thursday, creating extremely hazardous conditions for mariners. Strong winds combined with bitter Arctic air will also increase the risk of heavy freezing spray, particularly beginning Thursday and continuing into Friday.
Heavy freezing spray develops when strong winds whip cold lake water into the air, rapidly freezing on contact with vessels. This can cause dangerous ice accumulation, increasing the risk of capsizing for smaller boats and creating severe safety hazards even for larger commercial vessels.
Wind directions are expected to vary from northwest to southwest through the week, contributing to shifting wave patterns and prolonged rough conditions. The National Weather Service notes that Arctic air returning late week will further enhance freezing spray potential.
Mariners are strongly urged to avoid travel on Lake Superior during gale and freezing spray warnings. Harbor operators and shoreline communities along northeastern Minnesota and the Upper Peninsula should also prepare for periods of high waves and hazardous conditions near exposed shorelines.
These conditions mark one of the more significant marine hazards so far this season, with forecasters stressing that the multi-day nature of the event increases overall risk.
