One more quiet day ahead for Tuesday which will be followed by a brief period of active weather for Wednesday into early Thursday as a powerful area of low pressure moves quickly to the northeast out of the Rockies and Western High Plains — This system looks to bring a variety of potential hazards to northeast Minnesota and northwest Wisconsin from late Wednesday into early Thursday.
1: Rain and areas of fog (possibly dense)
2: A quick drop in temperature which may lead to a flash freeze
3: A narrow band of snow (possibly heavy)
4: Freezing rain and or sleet
4: Strong winds
5: Isolated thunderstorms Wednesday night
With so much warm air pumping north ahead of an approaching low from the southwest there’s no doubt that precipitation will begin as rain in northeast Minnesota and northwest Wisconsin late Wednesday afternoon or Wednesday evening, but given the dynamics of this storm plus strong cold air advection pushing in from the west, we may see a narrow strip of rain changing to snow with several inches of snow accumulation possible over a portion of the Northland for late Wednesday night/early Thursday morning.
A look at the temperature forecast valid from 6 PM Wednesday to 6 AM Thursday.
Temperatures are expected to range from the 40s to around 50 in northwest Wisconsin to the mid 30s in northern Minnesota Wednesday evening, but temperatures are expected to fall to the mid-teens to the 20s by 6 AM Thursday.
For Duluth: Temperatures around 40 at Midnight Thursday falling to 25 to 30 by 6 AM Thursday.
How quick the colder air rushes in and how much rain falls prior to the arrival of the cold air will determine if we see a flash freeze occur in parts of the Northland early Thursday morning, but the risk is definitely there.
Future radar valid 6 AM Wednesday to 6 PM Thursday.
Snow in blue
Rain in green
Mixed precipitation types in pink
Areas of drizzle are possible in the Northland during the day Wednesday with a steadier and potentially heavy band of precipitation lifting quickly NE across the area Wednesday night. Some precipitation which should be all snow may linger into the day Thursday.
Note: Areas of fog may develop in the Northland from Tuesday night into Wednesday evening, and some of this fog could become dense.
Widespread precipitation amounts of around a half inch, or more are possible in northeast Minnesota and northwest Wisconsin late Wednesday into early Thursday.
Parts of north-central Minnesota into the Arrowhead have the greatest chances for seeing snowfall accumulations of 3 or more inches for early Thursday morning but keep in mind this area may shift farther north or south in coming days, and snow totals may trend lower or higher as well. Stay tuned.
Strong winds are likely over much of the Plains, upper Midwest and western Great Lakes from late Wednesday into Thursday.
Wind gusts of 45 to 60 mph or stronger are possible in parts of southern Minnesota, Iowa and Wisconsin, with potential for northwest wind gusts of 25 to 45 mph in northeast Minnesota and northwest Wisconsin on Thursday.
Widespread High Wind Watches in effect for Wednesday-early Thursday stretching from parts of Colorado and Wyoming to southeast Minnesota and southwest Wisconsin, to as far south as north Texas.
Whenever you have a temperature contrast like the one will have on Wednesday this typically leads to a rather strong low-pressure system which tracks between the arctic air to the NW and the real warm stuff to the SE.
Here’s the 500mb forecast valid for Wednesday — Our system ejects NE out of the Central Rockies on Wednesday and is expected to be north of Lake Superior already by daybreak on Thursday.
The computer models continue to show some elevated instability pushing north/east out of southern Minnesota into eastern Minnesota and Wisconsin for Wednesday evening which may lead to the development of a few fast-moving thunderstorms over the aforementioned areas. It wouldn’t even surprise me if we see an isolated severe thunderstorm risk develop late Wednesday afternoon or Wednesday evening especially in the black outlined area on the animation below.
A major ridge over the Gulf of Mexico and an equally strong upper-level trough just offshore of the Pacific northwest today — The Northland is currently in a mild west to slightly southwesterly flow aloft with the upper ridging to our south, and the trough off to the west.
Well, the arctic air has returned to northwest Canada and much of Alaska today where temperatures are only in the teens, 20s and 30s below zero this afternoon.
Temperatures are running +10 to +25 degrees warmer than normal across the Central U.S. today and expect this trend to continue through Wednesday.