Numerous communities across the Upper Peninsula, including Ironwood, have issued water let-run notices to prevent homeowners' pipes from freezing.
With frost already more than 7 feet deep across the U.P., homeowners are struggling with frozen water lines, especially where there is little snow cover.
Many U.P. water customers are being asked to run their water at a pencil eraser width until further notice and keep the snow cover over the lines.
Bob Richards, of the Ironwood department of public works, said Monday just because warmer weather has arrived, it doesn't mean the frost that is causing the frozen pipes will disappear any time soon.
Hooray for 40!
On Tuesday, Gogebic Range residents were enjoying the first day above freezing for 2014. The thermometer had already shot up to 43 degrees by 2 p.m. Tuesday at the Hurley tourist information center. It was a balmy 42 on Wakefield's Sunday Lake.
Sub-zero weather is forecast to return later in the week, however, beginning on Friday.
On Thursday, the high will be around 34, with a low of 12 and 90 percent chance of snow.
The National Weather Service warns it could be a significant storm that will "take aim at the upper Great Lakes region" through Thursday night, and possibly into Friday morning.
As it stands now, the storm could include heavy snow and freezing rain over the U.P.
The heaviest snow is predicted for the western U.P., with 8 to 10 inches possible.
NWS officials said they'll have more predictions about the strength of the storm as the week progresses.
Ironwood received another 3 inches of blowing, drifting snow for the 24-hour period to 7 a.m. Tuesday, increasing the on-the-ground level to 26 inches.
Some areas of Minnesota received from 6 to 10 inches of snow Monday, according to the weather service.
The most snow in the U.P. Monday was 4.8 inches in Painesdale.