This is going to be a close call

Let's talk about the certainties of this next weather system on Monday and Tuesday. We know it is going to be considerably colder. By 00z Wednesday (7pm Tuesday) Temperatures drop to -14C at 850mb. The cold air advection continues into Wednesday as 850mb temperatures drop to -18c by the end of the day. Hint: It doesn't look like a lot of warming Wednesday. We also know we will see snow, but how much. That of course is the one-hundred dollar question! You may know by reading this blog that precipitation and precipitation amounts are one of the most difficult calls to make. One of the most difficult things to do is to pinpoint where the snow is going to fall. Many times we are correct on the amount of snow that will fall but the track changes and the snow ends up 50 miles away. Right now the NAM-Cobb output has us at about 2.5" of snow. I think this is good call to begin with as I really don't like the track of this system. It's too far north for my taste right now for a heavy snowfall. I'll show you a couple of examples here: The placement of the low here is about 100 miles too far north if you follow it I think it moves through just north of Indianapolis That's a lot of sleet for our area and diminishes the snowfall totals.
The east coast better watch out this has nor easter' and 'bombogenesis' written all over it!

I like the track on this model a little better. This is the GFS it has the low about 50 to 75 miles south of the above track on the European.
This is the 54 hour GFS which has the system crossing southern Illinois and going through Terre Haute.
This is the final graphic where the system phases across the east coast and makes a huge storm.

This storm also phases with the northern jet stream across Missouri so that makes it more interesting for us as far as energy and snowfall. Here's the 'fly in the ointment' for me. The first model that I've shown above (European) has been more consistent and is certainly the model of choice here. That would indicate a small snowfall of 2 to 3 inches. The National Weather Service has already considered one their famous 48 hour ahead time watches. I am so glad they did not issue it here because it saves me headaches today and tomorrow I really think it's too early to issue anything on this storm as it's still out in the Pacific. We'll have fun following it though!