As recently as Saturday, reports of vehicles falling through the thin ice on Wind Lake have underscored the danger of fluctuating temperatures on the surface of area lakes.
Tom Zagar, conservation coordinator with the city, confirmed that while much of the lake surface on Big Muskego was strong enough to support fishermen, the thickness can change depending on where you walk.
"Technically, a person can be supported on as little as two inches of ice, but it's when that ice thins that you have to be careful of," he said.
Most area lakes are recording approximate thicknesses of five inches, but as an early winter warm up is underway, the integrity of the ice is compromised. To make it dicier, rain is forecast for Thursday night, which can refreeze but create thinner layers of ice that aren't as strong.
According to the DNR, a number of factors can make ice unsafe: the depth of the water, a current, or an underlying weed bed. With the latter, the warm summer had created the perfect environment for the proliferation of weeds in spots on Big and Little Muskego Lakes, so where the ice may be solid in one area, it may be less so just a few feet away.
The recent snowfall may also have be a factor, as snow acts like an insulator against colder temperatures. The late cold snap meant that the ice didn't have much of a chance to thicken before our first snow on Dec. 20.
As always the best rule of thumb is to know the lake you're on, and if you're not sure, talk with local fishermen to determine if it's safe.