As much as a foot of snow could fall Sunday night and Monday morning across Northwestern Wisconsin, according to the National Weather Service in Duluth, while the Twin Ports could see 6-10 inches.
Much of the Northland is under a winter storm warning until 6 p.m. Monday. The warning area, which has been expanded, stretches from just south of Ely to Pine City and west to Fargo, and from Superior to Hurley and south to Spooner in Wisconsin.
The warning does not include Cook and Koochiching counties and northern Itasca and northern St. Louis counties. In Lake County, the warning only covers areas near Lake Superior. These areas are under a winter weather advisory and could still receive anywhere from 1-6 inches of snow.
As of 9 p.m. Sunday, snow was reported in Grand Rapids and Hibbing, while freezing drizzle was falling in the Twin Ports, Cloquet and east toward Ashland, the Weather Service reported. The snow will spread north and east across the region by early Monday morning.
The snow could be heavy at times, the Weather Service reported, and travel will become difficult, with slippery roads, blustery winds and reduced visibility, which are likely to affect the Monday morning commute. The worst conditions are expected between midnight and 6 a.m. in Northeastern Minnesota and between 6 a.m. and noon in Northwestern Wisconsin.
Weather Service forecasters described the area from Superior to Ashland as a bull's-eye, with high confidence of 10 inches of snow or more. Strong winds could cause isolated power outages along the South Shore of Lake Superior, they said.
Away from Lake Superior, snowfall totals will be lower, with 6-8 inches expected in Grand Rapids, Two Harbors, Silver Bay, Hinckley and Hayward; and 4-6 inches in Ely, Virginia and Grand Marais.
Small-craft advisories on Lake Superior are posted through Monday afternoon and evening from Taconite Harbor to Duluth and from Duluth into the Upper Peninsula of Michigan, with winds of 20-25 knots (23-28 mph) and waves between 4 and 8 feet expected.
Lakeshore flooding is possible along the South Shore but unlikely in Duluth, forecasters said Sunday afternoon.
After the storm moves out, temperatures are expected to plummet.
In Duluth, Monday’s high should be about 17 degrees, with readings falling throughout the day, the Weather Service reported. Tuesday will be partly sunny and cold, with a high of 3 degrees above zero.
By Wednesday morning, temperatures could be 15-20 degrees below zero with wind chills in the 30s below zero. Wednesday's high should be about zero, according to the Weather Service.
Temperatures should rebound into the 20s toward week’s end, with another chance of snow showers in the Twin Ports on Thursday.