Slippery Overnight

The National Weather Service has issued a FREEZING RAIN ADVISORY for Winnebago, Boone, Ogle, Lee, and Dekalb counties until 5 am on Sunday morning.  There is a boundary across Illinois tonight with warmer air to the south riding up and over the cold air at the surface.  Light precipitation has developed on a widespread basis across all of northern Illinois from the Mississippi River eastward to Lake Michigan.  Because of temperatures above freezing aloft, the drizzle is coating surface features with a thin layer of ice.  Exercise due caution if you are driving tonight through the early daylight hours on Sunday.  On Sunday a stationary front will hang in place from northwestern Indiana across central Illinois through northeastern Kansas as low pressure moves out of the Rockies into Kansas.  The temperatures will warm enough by Sunday afternoon that any precipitation that falls will be in the form of rain. It appears at this time as if the heaviest rain will pass well  south of the Stateline.  Rain will continue through the evening hours, and then switch over to sleet, freezing rain, and snow by midnight, and all wet snow later on Sunday night.  Some light snow may linger into early Monday morning.  By Monday afternoon drier air will move in from the plains, and skies will become partly cloudy.  High pressure will move across the area on Tuesday leaving skies mostly sunny, and with a southwesterly wind developing, temperatures will top out close to 40 degrees.  The next push of Canadian air will be with the passage of a cold front early Tuesday night.  Wednesday will be colder, but not drastically so, with the center of the Canadian high pressure passing eastward north of the Great Lakes to southwestern Quebec by 6 am on Thursday morning.  That sets the stage for the next weather system moving eastward across the plains.  Skies will become mostly cloudy on Thursday, and there could be a light rain/light snow mix across the Stateline on Thursday night that will last through Friday.  Next Saturday looks partly cloudy and a little colder with a high in the low 30's with high pressure from Canada taking control of area weather once again.    Drive Safely!
By meteorologist
Eric Nefstead