The changes in the jet stream pattern appear to be on track to push moisture into southeast Minnesota later tonight through Satuday evening. As the moisture meets up with the colder temperatures, accumulating snow is likely to occur from Austin through Dexter, Wabasha and on into Black River Falls, Wisconsin. Snowfall could be four inches or more in the region.
At this time, the continuity of the model data is holding firm in keeping the Twin Cities metro on the fringe of the snow band. We'll track the developing precipitation on radar as the system advances toward Iowa and Minnesota later tonight.
Confidence has heightened on the potential for significant snowfall and a Winter Storm Watch has been issued for portions of southeast Minnesota.
Blue shading highlights the Winter Storm Watch for Satuday. See more details from the La Crosse NWS Office.
Here is NOAA's Environmental Prediction Center's probability of snowfall of greater than four inches.
The forecast map from the NAM for 6PM Saturday places the surface low pressure in a good spot for snow over southeast MInnesota. The pressure gradient is not strong, thus the winds should remain on the order of 10 to 15 mph.
In case you missed it, the temperature dropped to four degrees below zero last evening in Ely before recovering to near ten degrees this morning.
Statewide it looks to be a quiet day with seasonal temperatures. Traveling southeast on Saturday from the Twin Cities? Keep tuned for updated weather forecasts.
By late Saturday evening some locations in southeast Minnesota could be enjoying such a lovely snowfall.
As I commented on Morning Edition, you really don't rush a good snowstorm. On Saturday afternoon we should be seeing snow falling at a moderate rate from Mankato through the southern extent of the Metro and on into west central Wisconsin.
Moisture was beginning to concentrate to our southwest as depicted in this water vapor satellite image from mid afternoon. Tonight will remain quiet, but the main event kicks in during the late morning hours on Saturday.
The blue coloring indicates colder cloud tops.
Winter Weather Watches/Advisories and warnings extend from southwest to northeast, from New Mexico to Wisconsin.
Click on this link to weather.gov to navigate for detailed forecasts.
Snow could accumulate four or more inches Saturday afternoon from near Fairmont through Waseca, and Rochester to Red Wing and into western Wisconsin. For the Twin Cities metro, snow will be heaviest toward Lakeville, where three inches look to be a good bet for now.
By nature the heaviest snow falls roughly 150 miles north of the track of the center of lowest pressure. This is not a particularly strong surface system,thus the winds are expected to be tolerable.
Follow the details of this enfolding weather story here at mpr.org with the support of the National Weather Service Office in Chanhassen.