A winter storm is expected to impact the upper Midwest starting Sunday evening. A winter storm watch will be in effect from late Sunday night through Tuesday afternoon. A mix of freezing rain and sleet will be possible tonight, especially for southeast Nebraska and southwest Iowa. This may cause travel problems with icy roads. Due to this icing, a winter weather advisory has been issued for a few counties across southwest Iowa, which will be in effect through 6am Sunday.
Precipitation will then increase in coverage and intensity by Sunday night, with a mix of rain, freezing rain, sleet and snow.
Timing: Light snow will begin Sunday night across northwest Iowa, with heavy snow occurring on Monday and Monday night. Further to the south across southwest Iowa, a mixture of precipitation will occur. Freezing rain, sleet and snow should develop Sunday night, then continue Monday into Monday evening. The most likely time for snow and ice accumulations is Monday and Monday evening. Light snow will then linger well into Tuesday.
Accumulations: Snow totals of 6 to 10 inches are expected across northwest Iowa with this long duration snowstorm. Areas east of the James River Valley, especially across southwest Minnesota and northwest Iowa could see upwards of a foot of snow in some locations. Across west central and southwest Iowa, 3 to 6 inches of snow will be possible, with up to one quarter inch of ice.
Impacts: Northerly winds between 10 and 15mph will be likely Sunday night and Monday. By Tuesday, northwest winds will increase up to 15 to 25mph. Snow covered roads are expected with this storm and will create hazardous travel conditions Monday into Tuesday. Blowing snow by Monday night, may lead to drifting of the snow.
As we showed earlier this afternoon on our Facebook page, there still remains some uncertainty with the track of the low as shown above. The NAM and high res NAM show a big time east/southeast shift in the track, which would shift the area of heavy snow. The GFS has also shifted things east, but a less dramatic shift compared to the NAM. At this current time, it is something that is closely being monitored since the European and Canadian model continue to focus on northwest Iowa. The winter storm watch that is currently out has taken into account a slight shift in track.
We will continue to keep an eye on the very latest developments and will provide updates when there is new information to pass along.