Winter Weather Update

Noon Update: Going forecast still looks to remain on track with the main surface low developing in the southern Plains early Tuesday and moving into Ohio by Wednesday morning.  I do have a feeling that totals are going have a significant range from north to south with this system with possibly southwestern Wisconsin picking up anywhere between 6"- 12" and further southeast across south-central Wisconsin and north-central Illinois totals could range closer between 8"- 14" (maybe higher).  With such a dynamic system there could even be a little thundersnow as the low passes to the south which could increase snowfall rates for some.  The very top image are winds several thousand feet above (300 mb) roughly around 6pm Tuesday night.  What I want you to notice are the darker blues across northern Wisconsin and southern Illinois.  These are areas of stronger winds, or jet streaks, within the main jetstream.  Typically when you have them positioned like that - one almost on top of the other - it's usually a good indication of strong lift that will be present in the atmosphere.  With this type of lift that is what could produce some of the heavier snows across the western Great Lakes.  Snow will likely begin to overspread the region beginning Tuesday afternoon with the brunt of the system coming after 8pm or 9pm.  It is after this time that winds will begin to pick up with gusts nearing 40mph after midnight and lasting through Wednesday morning.  After 8pm Tuesday night, travel will not be advised through Wednesday morning.  

8:00 am: A potentially dangerous and significant storm continues to threaten the Stateline beginning Tuesday night and lasting through Wednesday morning.  A very strong jetstream continues to dig out in the southwest part of the U.S. this morning and that will help develop a surface low in the southern Plains later this evening.  The current track of this system takes the low from eastern Texas Tuesday morning and quickly strengthens it as it moves northeast into the mid-Mississippi River valley before moving northeast of the Great Lakes by Wednesday morning.  With this current track the heaviest of the snow would fall right through southern Wisconsin/Northern Illinois and points southwest.  Some locations could stand to receive over 12" of snowfall.  This type of track would also favor thunderstorm.  Since this system is very dynamic from the surface all the way through the upper levels, we may actually see 'thunderstorms' develop Tuesday night which, just like in summer, could produce higher snowfall rates for a duration of time.  I do have a feeling that we are going to see a large gradient from north to south concerning snow totals with this storm. 

Since we are still roughly 36-48 hours away from the main event there is still a chance that this system could track either a little further north or south.  The track is something that we will monitor very closey throughout this evening and Tuesday morning and that's why we likely won't have a snowfall forecast for you until tonight.  The most critical time frame will be late on Tuesday and into Wednesday morning.  This will be when the heaviest of the snow is falling and the winds will also become very gusty which could create some blowing and drifting concerns.  Travel during this period will not be advised - so if you have any last minute errands you need to run I would suggest doing them today.

Stay with WTVO as we continue to monitor and update you on this winter storm.

Winter Weather Advisory remains in effect for Green, Rock and Walworth counties in southern Wisconsin from 3pm this afternoon until 3pm Tuesday afternoon.

Winter Weather Advisory remains in effect for Stephenson and Jo Daviess counties in northwest Illinois until noon Tuesday.

Winter Storm Watch will go into effect Green county in southern Wisconsin and Stephenson, Jo Daviess, Carroll and Whiteside counties from Tuesday afternoon until Wednesday afternoon.

A Blizzard Watch will go into effect for Rock and Walworth counties in southern Wisconsin and Winnebago, Boone, McHenry, Ogle, Lee and Dekalb counties in northern Illinois from Tuesday afternoon until Wednesday afternoon.