A storm system will intensify rapidly as it moves from the central plains toward Wisconsin Saturday night and Sunday. Snow, sleet, freezing rain and rain are all expected from late Saturday night through Monday. It is possible that many locations will experience significant ice accumulations in addition to moderate to heavy snow on Sunday.

As the precipitation initially breaks out late Saturday night or early Sunday morning it will be all snow. The snow will gradually transition to freezing rain or rain south of a line from roughly Port Washington to West Bend to Beaver Dam. North of that line, it's likely the precipitation will remain in the form of snow throughout Sunday. Late in the day on Sunday or Sunday night, areas receiving freezing rain or rain will see the precipitation transition back to all snow.

Since the transition zone from snow to freezing rain to rain will be located directly through southern Wisconsin, even a slight change in the storm system's track from that currently expected could lead to dramatically different conditions.

Here is my county-by-county forecast as of Saturday afternoon:

Milwaukee and Waukesha Counties

Sunday -- Snow in the morning, changing to freezing rain or rain in the late morning and afternoon. Accumulation of 3 to 4 inches ... Ice accumulation of less than one quarter of an inch ... Highs in the mid-30s ... East winds 10 to 20 miles per hour.

Sunday night -- Snow or freezing rain or rain until around midnight ... Light snow likely after midnight ... Windy with areas of blowing snow after midnight ... Snow accumulation of 1 to 2 inches ... Total snow accumulation 4 to 6 inches ... Ice accumulation of less than one quarter of an inch ... Lows in the mid-20s ... Northeast winds 15 to 20 miles per hour.

Racine and Kenosha Counties

Sunday -- Freezing rain or snow in the morning ... Rain or freezing rain in the afternoon ... Snow accumulation of 2 to 4 inches ... Ice accumulation of up to one quarter of an inch ... Highs in the mid-30s ... East winds 10 to 20 miles per hour.

Sunday night -- Freezing rain or rain or snow through around midnight ... Light snow likely after midnight ... Snow accumulation up to 1 inch ... Ice accumulation of less than one quarter of an inch ... Lows in the mid to upper-20s ... Northeast winds 15 to 20 miles per hour.

Ozaukee County

Sunday -- Snow in the morning with rain or freezing rain or snow in the afternoon ... Snow accumulation of 4 to 7 inches ... Ice accumulation of less than one quarter of an inch ... Highs in the low-30s ... East winds 10 to 20 miles per hour.

Sunday night -- Snow or freezing rain through around midnight ... Snow after midnight ... Windy with blowing snow after midnight ... Snow accumulation of 2 to 4 inches ... Total snow accumulation 6 to 10 inches ... Lows in the mid-20s ... Northeast winds 15 to 25 miles per hour.

Washington County

Sunday -- Snow in the morning ... Rain or freezing rain or snow in the afternoon ... Snow accumulation of 4 to 7 inches ... Ice accumulation of less than one quarter of an inch ... Highs in the low-30s ... East winds 5 to 15 miles per hour.

Sunday night -- Snow or freezing rain through around midnight .. Snow after midnight ... Windy with blowing snow after midnight ... Snow accumulation of 2 to 4 inches ... Total snow accumulation 8 to 12 inches ... Lows in the low-20s ... Northeast winds 15 to 20 miles per hour.