Lake Winnebago Ice Out: The Last Ice Is Gone—Here’s What It Means

It’s official: Lake Winnebago ice out was called on March 20, 2025.

The last ice on Lake Winnebago has vanished—and just like that, spring has its first real foothold. Around here, ice out means it’s time to start thinking ahead: boaters start dreaming, anglers start planning, and the whole Fox Valley begins to thaw right along with the lake.

Once ice off Lake Winnebago is confirmed, the Corps shifts focus—from holding winter pool levels to preparing for the spring refill.

That refill supports all the things we look forward to including fish spawning, wetland health, shoreline protection, and a strong start to summer recreation.

While flood risk management always comes first, the Corps also works to balance the needs of anglers, boaters, shoreline property owners, and more. Their annual Lake Winnebago regulation strategy, developed with stakeholder input, guides their approach throughout the open water season.

Want to track current lake levels, flows, or snowpack? Check out the weekly update here.

Most years, Lake Winnebago goes ice-free in late March or early April.

There are outliers—March 6, 2024 was the earliest ice out we’ve seen in two decades, while April 22, 2013 holds the record for the latest. But more often than not, the lake opens up somewhere between March 27 and April 6.

The exact timing depends on the kind of spring we get—some years move fast, others take their time. But if you’re keeping an eye on the shoreline, those last few days of March are usually a good time to start looking for open water.

This year, ice out was called on March 20—a little earlier than usual, but still right in the mix with what we’ve seen in recent years.

It’s a common question—and a good one.

To keep it simple:

• The U.S. Army Corps of Engineers manages water levels and operates the dams on Lake Winnebago.

• Here at Fox-Wolf, we focus on clean water, habitat health, and community education throughout the watershed.

We don’t make decisions about lake levels—but we care deeply about how those decisions ripple across the system, from rivers and wetlands to fish, wildlife, and recreation.

Across the Fox Valley and throughout the Fox-Wolf Watershed, Lake Winnebago ice out marks a true seasonal shift.

It’s when docks go in, bait shops get busy, and neighbors start swapping stories about what they’ll catch—or where they’ll paddle—first. It’s more than a date on the calendar. It’s a moment of change, full of promise—for Lake Winnebago and for the communities that live with it, on it, and for it.

Water levels impact everything from fish habitats to your favorite outdoor activities. Stay tuned to our Basin Blog for more upcoming posts highlighting how water level management decisions shape Lake Winnebago’s future—and your next lake adventure.

Want more info right now?

• U.S. Army Corps of Engineers – Lake Winnebago Water Levels
• Lake Winnebago’s Dynamite Past
• Lake Winnebago Recreation & Fishing Information – Wisconsin DNR
• About Fox-Wolf Watershed Alliance