Accumulating Snowfall Likely for the Weekend

The winter season got off to a slow start at the beginning of December with mild weather lasting through much of the month, as well as into the beginning of January.  But a pattern change in the atmosphere will lead to a colder air mass moving southward, helping to bring temperatures down quite a bit as we enter into the beginning of January.

Often times when these big pattern changes take

place, strong storm systems develop as the atmosphere tries to balance itself out.  This upcoming pattern change means our weather pattern turns a lot more active heading into the weekend, as well as into next week.  A cold front moving in from the north late Tuesday will keep the threat for patchy freezing drizzle during the evening and early overnight.  A Winter Weather Advisory remains in effect for Stephenson, Jo Daviess, Carroll and Whiteside counties until Midnight.  Untreated surfaces may become slick early Wednesday.  Wednesday will be our only 'quiet' day this week as another low pressure system moves through southern Illinois Thursday morning and afternoon.  This system doesn't look overly strong but could still bring some flurries or light snow across northern Illinois through the afternoon.

A stronger storm system is set to develop east of the Rockies Friday before moving into the Mid-Mississippi River Valley Saturday and up the East Coast by Sunday.  This storm system will likely bring accumulating snowfall to much of northern Illinois and southern Wisconsin late Friday and much of Saturday.  Exact totals are still in question as the storm track continues to shift, but we can say with a decent amount of confidence that we'll see accumulating snow from this system.

Strong dynamics in the atmosphere will allow the wind field to strengthen quite a bit around the low pressure system Friday night and Saturday.  This means gusty northeast winds will develop, with gusts likely over 30mph during the day Saturday and Sunday.  The snow that comes down will be a dry snow because temperatures will be falling through the 20s Friday night and Saturday afternoon.  Blowing and drifting snow will be more than likely during the day Saturday, as well as for Sunday.

Once the system passes its the cold that takes front seat for the end of the weekend and early next week.  Highs will struggle to make it out of the teens Sunday with wind chills falling below zero Saturday night through Monday morning.