Heavy Freezing Spray Warning Issued for Lake Superior Near Minnesota and Wisconsin

Alert Details

The National Weather Service in Duluth, MN, has issued a Heavy Freezing Spray Warning and a Gale Warning for specific maritime zones in Lake Superior. The alert is classified as a severe threat with a high likelihood of occurrence.

Affected Areas

The warning covers the following geographic regions:

• Minnesota: Taconite Harbor to Silver Bay Harbor
• Wisconsin: Sand Island to Bayfield, and Oak Point to Saxon Harbor
• Offshore: Outer Apostle Islands beyond 5 nautical miles from the mainland

What You Should Do

Mariners are strongly advised to prepare for dangerous ice accumulation on their vessels. If possible, remain in port or avoid the warning area entirely. Those already at sea should seek safe harbor, alter course, and secure their vessels for hazardous conditions to prevent catastrophic loss of stability.

Expected Conditions

• Ice Accumulation: Heavy freezing spray is expected to accumulate at a rate of 2 cm per hour or greater.
• Wind Speed: North winds of 20 to 30 knots are forecast, with gusts reaching up to 35 knots.
• Wave Heights: Significant waves between 10 and 15 feet are expected.
• Impacts: Operating a vessel in these conditions is hazardous. Rapid ice accretion on decks and superstructures can lead to a loss of stability. Additionally, freezing spray may cause mechanical and electronic components to become inoperative, while strong winds and high waves may reduce visibility or capsize vessels.

Timeline

The Heavy Freezing Spray Warning and Gale Warning are effective immediately and are scheduled to remain in effect until 4:00 PM CDT this afternoon, March 16.