Some snow and rain tonight-early Monday; more rain at times Monday with areas of freezing rain along the North Shore

A mixture of snow and rain with some areas seeing all snow will develop or move into the Northland this evening and overnight with some slushy snow accumulations possible late tonight which could lead to some slick travel conditions overnight/early Monday morning.
Occasional rain and drizzle are likely in the Northland on Monday, and there may even be an isolated thunderstorm as we see a slight increase in elevated instability along with a plume of steeper mid level lapse rates advecting into our area.
Surface temperatures along the North Shore of Lake Superior (higher terrain) will be slow to climb above freezing on Monday which increases the chances that periods of freezing rain will occur with some ice accumulations possible inland from Lake Superior along the North Shore.

Note: A mixture of rain and snow possibly changing over to all snow at times will develop in Duluth and Superior this evening (~8-10 PM) Warmer air moving in aloft will cause any wintry precipitation to change over to mostly rain during the day Monday, however, if surface temperatures are slow to climb above freezing, then we could be dealing with some sleet and freezing rain during the day Monday. It will also be breezy in the Twin Ports as east winds gust to around 20 to 30 mph tonight through Monday night.

18z NAM 3km model simulated radar forecast thru 1 AM Tuesday.

Blue=Snow

Green=Rain

Pink/Purple=Mixed precipitation

Precipitation totals of around a half inch are possible over northeast Minnesota and northwest Wisconsin through Monday night with higher amounts approaching an inch possible along the North Shore of Lake Superior.

Note: 2.24″ of precipitation has fallen so far this month at Duluth, Minnesota which is a little over a quarter inch above normal to date, or some 115% of normal. Will be adding to this month’s precipitation total over the next 24 hours.

National Weather Service ice accretion forecast valid through Monday evening shows generally <0.10″ amounts over parts of the Northland, mainly along the North Shore, and also over portions of north-central and northeast Wisconsin.

Here’s my snowfall accumulation forecast.

Note: Most of this snow falls tonight, except over the Arrowhead or in that 3-5″ zone where snow could linger into Monday afternoon.

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Look at this temperature contrast this afternoon, ranging from the teens along the eastern shores of Hudson Bay Canada, to around 100 degrees in southwest Texas (Laredo, TX)

A big time temperature contrast will be in place on Monday with well below normal temperatures in the 30s in northeastern Minnesota and well above normal temperatures in the upper 80s and lower 90s in eastern Nebraska and western Iowa.

An active weather pattern will be in place through midweek as a large trough over the western US moves to the east. Southwest flow aloft is in place ahead of the approaching trough from the west which will lead to increasing amounts of moisture and precipitation across much of the Northland through Monday evening, with some more rain possible Tuesday and early Wednesday especially in parts of northwest Wisconsin.

Water vapor loop from Sunday, April 25, 2021.