Winter Storm Delphi Winding Down Across Northern Plains, Upper Midwest

Jon Erdman
Published: December 1,2015

Winter Storm Delphi will wind down through Wednesday morning across the northern Plains and Upper Midwest after dumping up to a foot of snow in parts of northern Nebraska and eastern South Dakota. Portions of southwest Minnesota and northwest Iowa have seen top snowfall totals of 9 inches.
(LATEST NEWS: Delphi's Impacts in the Midwest)
(MORE: Science Behind Naming Winter Storms)

Current Radar

(INTERACTIVE: Radar | Winter Alerts)

Winter Storm Delphi Last Bit of Snow

Snowfall Forecast

Here is the general outlook of additional snowfall expected through Wednesday morning:

• Locally up to 3 inches of snow possible: Northeast Minnesota, as a band of light to moderate snow lingers through early morning. Later in the morning, a band of snow may impact portions of northern Illinois with a couple of inches of snow, although downtown Chicago can expect rain or a wet snow that struggles to accumulate.
• Scattered flurries and snow showers: A broad area from Minnesota and Iowa, eastward to Lake Michigan can expect a few periods of light snow through the overnight. By the predawn hours, any lingering snow activity should be confined to southern Wisconsin and northern Illinois.

(FORECASTS: Duluth | Chicago)

Tuesday Night's Forecast

Snow and Ice Reports

As expected, the heaviest snow totals, so far, ranging from 8-12 inches, fell over parts of eastern South Dakota, northern Nebraska, southwest Minnesota and northwest Iowa.
The top snow totals from the storm as of Tuesday night are 12 inches near Valentine, Nebraska, followed by 12 inches near Mosher, South Dakota. Minnesota has seen up to 9.5 inches in Madison, while Iowa has seen up to 9 inches in Hull.
In Sioux Falls, South Dakota, 4.7 inches of snow had fallen as of 1 p.m. CST Monday, with 3.7 inches of that falling in just two hours and as of early Tuesday afternoon 9.3 inches had piled up at Joe Foss Field (Sioux Falls Regional Airport) on the north side of the city.
Incidentally, the combination of Delphi and Winter Storm Bella pushed Sioux Falls to its fourth snowiest November on record, with 17.3 inches of snow. This is already more than half of the snow that fell all last season (31.9 inches) and is snowier than the 2011-2012 season (15.9 inches).
A burst of moderate to heavy snow moved into the Minneapolis/St. Paul metro area early Monday morning, dumping 1-3 inches on parts of the Twin Cities and another band of snow moved through the area Monday evening. Mpls./St. Paul International Airport measured 3.8 inches of snow through midnight Monday night.
Sunday night into early Monday, Denver saw some light snow accumulations from Delphi, with 1.5 inches officially measured at the airport northeast of the city.

Snowfall Totals

Freezing rain has also been observed with 0.25" of ice reported in Carroll, Iowa through 12 p.m. Monday. Roads and sidewalks iced over in Fort Dodge, Iowa early Monday morning.

Winter Storm Delphi Setup

Forecast location of the upper-level low pressure system on Tuesday in the Great Lakes. This system stalled in the Great Basin over much of the Thanksgiving holiday weekend.

Low pressure in the upper atmosphere had been stuck swirling over the Great Basin during the Thanksgiving holiday, trapped to the south of a corresponding area of high pressure aloft in an atmospheric logjam known to meteorologists as a "Rex block".
As a result, the weather had been rather stagnant and unchangeable, with periods of freezing rain, sleet and snow in the Plains and West from Winter Storm Cara in recent days.
Now, that blocked-up jet stream pattern has finally given way.
The upper-level low mentioned above is now pivoting east into the Midwest and Great Lakes. As it does so, moisture in the atmosphere will be lifted, and cold air in place will yield a few remaining areas of snow from the Corn Belt through the western and central Great Lakes.

MORE: Winter Storm Delphi (PHOTOS)