Here we are, the 10th day of January and my shovel sets quietly in the corner, waiting for the day I shake off the dust and cob webs to scrape the driveway. That's right, nearly half way through the winter and I've lived shovel free. A blessing for most of you, a curse for me.
The lack of snow to date can be a seasonal indicator (in other words It's not your year), that's the reason why I'm being cautious about the next system and its threat of accumulating snows over parts of the central Midwest Saturday. Here's where the system is located Wednesday night. The energy just entering the data rich west coast.
From here things get tricky as the storm advances towards my area. What concerns me is the strength and depth of dry surface air that will act as a wall to the northern extent of the snow shield. On this surface depiction you can see the east winds delivering the dry air and the sharp cut-off to the snow near HWY 20. The late December blizzard was similar in this respect with a very hard edge to the accumulating snow near and along I-80. This is going to make for a very difficult forecast in my local area. Chances are you are either in or out....little if any transition zone.
So, the big challenge is not if it will snow, it's how far north it gets into Iowa and Illinois. To help with that issue we go to the latest available snow forecasts. Here's the 0Z NAM.
Now the 0Z GFS.
The 0Z Canadian GEM
The 0Z EURO
A regional perspective of the EURO.
Here's the probabilities of at least an inch of snow, which are significant for a large part of the central U.S.
The big take away from tonight's data is the fact Missouri is really under the gun for heavy snow, especially the area near and southwest of St Louis. Undoubtedly winter storm watches are going up there. They could extend into far southern Iowa and parts of central Illinois. Winter weather advisories will eventually be posted on the north edge of the snow band and could extend up to I-80 in Iowa and Illinois.
Keep in mind that the upper air date really improves Thursday and that will improve forecast accuracy. We will have a better handle by evening where that sharp cut-off line to the northern edge of the snow sets up and whether or not I will need to use the shovel.
Last but not least, I've been harping on the impending change to a colder and snowy pattern since before Christmas, especially late January and February. I'm passing on this jet stream forecast for January 24th on the GFS. This my friends is an ugly look with bitter cold air surging into the U.S.
Just look at the temperature anomalies at that time.
The GFS has this for lows.
And this for wind chills.
That's the real deal and what I've been fearing since back in the fall. I actually hope the model is wrong. Even I hate frigid conditions like that! Roll weather...TS