A CHANGE OF PLANS, MAKE THAT TRACK...
Before we get into the next storm, just a little recap of what went down in many parts of my area with the last storm. I'll start you off with a couple shots from my meteorologist Rebecca Kopelman, my weekend contributor here on TSwails. She is better known to you and especially me as RK. Look at the happy face outside her place in Marion, Iowa. Snow halfway to her knees!. So exciting for a girl from Florida!
This is RK's makeshift measuring stick which came in just short of a foot. Storms like this are pretty rare in SE Iowa. Knowing RK she probably calculated it in centimeters and reported it as 30 inches. Just kidding! Thanks for all you do buddy.
Here's the heavy snow swath where those big 6-12" totals were common.
Another perspective showing the bullseye near and north of I-80. There was some impressive banding with thunder and lightning in spots that produced 2" per hour snowfall rates. That's a beautiful thing!
After another chilly but quiet New Years Eve day and night the next weather maker ejects into the Midwest from the south New Years afternoon and night. The important change from yesterday is a less phased system. That implies a weaker intensity and track that is further southeast. That does reduce overall ice and snow amounts but it also means the axis of wintry weather is now further east involving more of my counties in Illinois. It also means my far northwest counties may be missed or have minimal impacts with little to no snow where 3 or 4 inches was indicated yesterday.
Here is the latest track which could still deviate north or south. If there is further weakening ( a recent trend) I could see the track going further southeast leaving much of my Iowa counties (but the far SE) and NW Illinois dry. That's a concerning trend that I will be monitoring in future model runs.
Assuming the latest guidance holds there is a long swath of wintery weather that the Weather Prediction Center shows running from the Texas Panhandle to Wisconsin and Michigan the next couple of days.
By New Year's night you can see much of my area from the Quad Cities north with 50-70 percent odds of 1 inch of snow or more.
Of more concern is a period of freezing rain, especially in SE Iowa and WC Illinois that could lay down a hazardous glaze. The WPC odds for that are around 80-90 percent.
Due mainly to the ice threat the winter storm severity index does show some moderate impacts in Missouri and Kansas with only minor impacts currently indicated in my local area.
Models are still struggling a bit with phasing and I still have only moderate confidence in the overall track and that should be clearer later today. I'll feel better about pinpointing precipitation type, location, and amounts once we see the system eject northeast Thursday afternoon. Meantime, here's some model guidance on snowfall totals. These are not forecasts, just guidance that is used to make forecasts. As it stands now the best chances for accumulating snow looks to be southeast of a line from Des Moines to Cedar Rapids and near Dubuque. There will be a very sharp cut-off to the northwest extent of the snow band.
The Canadian GEM
The 12 NAM
The 3k NAM
That's the latest and greatest on where we stand going into the last day of 2020. A year I'll never forget but would like to. Don't let the door hit you in the rear! Have a happy and safe New Years Eve and of course, roll weather...TS