A MANITOBA MAULER

Before we get into the winds and associated Arctic front to come. Here's a refresher on our recent transition to winter weather. Let's start with the average 7-day temperature departures over the past week.

The past 3 days locally have been even colder, running 15–17 degrees below normal to start December.

To date, we haven't seen much for snow anywhere in the Midwest so far this season. You can see below the seasonal snowfall totals as of December 3rd around the Midwest. That's pretty anemic.

Here's a larger perspective of the nation's snowfall as a whole.

Now compare that to what we had at the same time last year, and it's obvious 2023 was not much better.

However, I would be remiss if I did not mention that after our slow start last year, we went to town in the first 2 weeks of January with some areas seeing nearly 30 inches of snow in a week with back to back storms and Arctic air. By the time winter was over, many of us ended up with 2–4 feet of while gold and an above average snow season. Take a look.

By the way, the skiff of snow we experienced Monday morning was enough to allow Steve Gottschalk, my weather folklore guru, to break out 5 long-time formulae used to predict seasonal snow by our ancestors. He sent me this:

Hey Terry, here are the 5 snowfall formulae I have to work with:

Date only (December 2nd) - 2 more snows.

Days since the New Moon - 1 more snow.

Days since the New Moon + date - 3 more snows.

Days since the Full Moon - 17 more snows.

Days until Christmas - 23 more snows.

The average of all 5 is 9.2 snows, or you can throw out the high and low projections of 1 and 23 that skew averages, and get 12 more snows. I'd say it's more like we end up with an average of 17 to 23 snows?

Thanks to Steve for the insightful methods and numbers. Just for kicks, let's say we split the number he is thinking between 17 and 23. That gives us 20 more snows. If all told, the average per snow was 1.5 inches, that would get us 30 for the season. Not a great year for snow but only a few inches below normal. Right now I would take it and be somewhat happy.

THE MANITOBA MAULER

Fortunately, it's not January, or what's coming could be even worse. As it is, it won't be pretty as a tentacle of Arctic air breaks loose and plows through the Midwest tomorrow night. Known as a Manitoba Mauler due to its origination area, this thing means business. Ahead of it, a deceptive day sets up, with SW winds and highs that reach the upper 30s north to the low to mid 40s south. Around 3:00 in the afternoon, the Arctic air hits the north and surges through the entire area in several hours time. When the front hits, you will know it by the howling north wind that rapidly comes to life. In a snap, gusts will reach at least 40 mph (potentially stronger). Look at the packed isobars over the region around 6:00 Wednesday evening.

Here's a closer perspective. If the powerful momentum found aloft can reach the ground, 50 mph gusts are possible in the north Wednesday night.

Stout cold air advection and strong forcing will whip up some snow showers that could initially be mixed with rain. It is possible that some snow squalls form that could produce some minor accumulations. A few areas in the north could see up to an inch, with most spots areawide witnessing a dusting in brief but intense snow showers. Models suggest this for accumulations. Notice on the CAMS such as the 3k NAM and HRRR, the narrow plumes produced by what appear to be stronger squalls moving rapidly from NW to SE late Wednesday or early Wednesday evening.

The EURO

THE CANADIAN GEM

The 3k NAM

The HRRR

Temperatures are going to crash behind the front as well. At Independence, Iowa, the temperature is shown going from 39 at 2:00pm to 9 at Midnight. A 30 degree drop in just 10 hours. The EURO indicates this for lows.

With that wind cranking, wind chills reach ugly levels Wednesday night, down around 11 below in the north to 5 below south.

Fortunately, this is a quick hitter and the cold and winds gradually ease off by Thursday afternoon. Highs should eventually reach the upper teens NE to lower 20s elsewhere. Unfortunately, wind chills will remain in the single digits most of the day despite a fair amount of sunshine.

HOORAY FOR THE WEEKEND

I am happy to say the weekend will see substantial improvement as the upper level winds turn more westerly, allowing a more moderate brand of temperatures Saturday and Sunday. Highs should get into the 40s both days, with a 50 possible in the south Sunday. Conditions look high and dry!

Have a nice day but keep a watch over your shoulder. That mauler is on the march and a nasty night is ahead. Roll weather...TS