ICY SUNDAY UPDATE...
Warmer air and moisture has been on the move this morning and that has pushed temperatures in the Midwest to the warmest levels since Christmas Eve. The one change that has happened is a little bit of a northern progression of the warmth.
Because of the lack of snow in southern Iowa the chances for a glaze of ice has increased near and south of I-80. Temperatures as of 10 AM:
Some areas in Missouri are climbing above freezing for the first time in over two weeks. Temperatures will continue to climb into the 20s and 30s but the snowpack in Iowa, Wisconsin and Minnesota will likely prevent temperatures from going above freezing there today. The northern extent of the warmth has lead to Winter Weather Advisories being extended to just south of I-80 in Iowa and along 80 in Illinois:
Here's a radar snapshot right before 10 AM -- a lot of this is not hitting the ground just yet because of how dry it is at the surface:
This winter system will be moving through the Midwest today and tonight. This is the latest run of the hi-resolution NAM:
The big challenge today is precipitation type. And even though there will be some locations that get above freezing, the ground is still very cold and will likely lead to ice accumulating at the surface. Now I think the model above is a little too aggressive with the freezing rain, as this is what it's putting out for amounts:
Some amounts, especially in southeastern Iowa are a bit too high. Here's the latest NAM - pretty similar:
And the least aggressive - the GFS:
Here's the consensus from the NWS offices --
In general a glaze to 0.10" of ice possible through much of Missouri, southern Iowa and portions of southern and central Illinois. Some sleet and snow accumulation possible late in the afternoon and evening up to an inch.
Further north into Iowa and extreme northern Illinois some freezing rain will be possible. But sleet/snow mix will be more likely with colder temperatures. Minor accumulation expected.
Precipitation will wind down by midnight but with temperatures below freezing overnight the potential exists for slick roads through the night into Monday morning.