Monday, November 30, 2015

Winter Storm Delphi Bringing More Snow to Northern Plains, Upper Midwest, Including Minneapolis

Jon Erdman
Published: November 30,2015

Winter Storm Delphi continues to dump snow, heavy at times, along with some sleet and freezing rain on the northern Plains and Upper Midwest. Snowfall rates of one to locally more than two inches per hour have been reported from Delphi at times on Monday.
(LATEST NEWS: Delphi's Impacts in the Midwest)
The snow will create potentially dangerous travel conditions in those regions, impacting metro areas such as Minneapolis/St. Paul, Sioux City, Iowa, and Sioux Falls, South Dakota. Locally up to a foot of snow is possible in some areas by the time the heaviest snow winds down later Tuesday.
(MORE: Science Behind Naming Winter Storms)

Current Radar
As of Monday evening, the National Weather Service had posted winter storm warnings in parts of four states, including northeastern Nebraska, eastern South Dakota, southwest/south-central Minnesota and the northwestern half of Iowa. Winter weather advisories are in effect across a larger area from central Nebraska to northern Wisconsin and northeast Minnesota, where somewhat lower snowfall totals are anticipated.

Current Alerts

Winter Storm Delphi Snow Forecast


Snowfall Forecast

With some uncertainty remaining in the forecast depending on how the storm system evolves, here is the general snow total outlook through Tuesday night:
  • At least 5 inches of snow possible (locally up to 12 inches): parts of northeast Nebraska, eastern/central South Dakota, extreme southeast North Dakota, the northwest half of Iowa, southern/central/northeast Minnesota, and northwestern Wisconsin. This includes Sioux City, Iowa, Sioux Falls, South Dakota, Watertown, South Dakota, Mankato, Minnesota, Duluth, Minnesota, and Minneapolis/St. Paul.
  • Lighter snowfall possible: Northern Minnesota, eastern Colorado, northern Kansas, western/central/southern Nebraska, western South Dakota, southern North Dakota, northeast Wisconsin and the Upper Peninsula of Michigan. This includes Fargo, North Dakota, Omaha, Nebraska, La Crosse, Wisconsin, Bismarck, North Dakota, and North Platte, Nebraska.
  • Ice: Light ice accumulations are possible from central and northeast Kansas to central Iowa, extreme southeast Minnesota, west-central/northern Wisconsin, and the Upper Peninsula of Michigan.
(FORECASTS: Omaha | Sioux Falls | Minneapolis/St. Paul)
Parts of southeast South Dakota, northeast Nebraska and northern Iowa just finished digging out from Winter Storm Bella, which dumped up to 18 inches of snow near Sioux Falls Nov. 20.
At the same time, Minneapolis/St. Paul finally picked up its first measurable snowfall of the season on Thanksgiving Day, their seventh latest "first snow" of the season on record.
The last snowstorm of 6 inches or more in the Twin Cities (airport) was April 3-4, 2014. The last official 10 inch snowstorm at the airport was Dec. 9, 2012 when 10.5 inches accumulated.

Winter Storm Delphi Snow Timing

Into Early Tuesday Morning

Snow, possibly heavy, continues in parts of the northern and central Plains, including South Dakota, North Dakota, northern Nebraska, parts of northwest Iowa, as well as Minnesota. Mixed wintry precipitation is expected from central Iowa into far southeastern Minnesota and into northeastern Wisconsin and the Upper Peninsula of Michigan.
Some blowing and drifting snow is also possible in the Dakotas and Nebraska Monday night.
Travel should be avoided in the areas mentioned above, including I-35, I-94, I-90 and I-29.
Dark blue shading indicates areas where snow is most likely. Pink areas indicate either rain or snow may fall. Purple-shaded areas indicate sleet or freezing rain is possible.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Tuesday

Leftover snow is possible in the northern Great Lakes and Upper Midwest, from Michigan's Upper Peninsula to northern/western Wisconsin, Minnesota, Iowa, northeast Nebraska and parts of the Dakotas.
This has the potential to disrupt both the morning and afternoon commutes in Minneapolis/St. Paul, and leftover snow and wind in the morning could also pose problems in Sioux Falls.
Snow lingering snow or a rain/snow mixture may pivot through the Great Lakes on Wednesday, however any accumulations will be minor.

Tuesday's Forecast

Snow and Ice Reports

Late Monday morning and into Monday afternoon, heavy snow was reported in parts of northeast Nebraska, southeast South Dakota, southwest Minnesota, and northwest Iowa. 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 9 p.m. 8 inches had piled up just south-southeast of Sioux Falls.
Farther south, 8 inches of snow has accumulated in Sioux City, Iowa, as of just before 4 p.m. CST. Nebraska has also measured some decent snowfall totals with 7.5 inches near Grant and 7 inches south of Valentine as of 1 p.m. CST. South Sioux City, Nebraska reported 6.5 inches of snow through 4 p.m. CST. In southwestern Minnesota, Luverne reported just over 7 inches of snow through 6:30 p.m. CST.
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. St. Paul measured 4 inches of snow through 9 p.m. CST.
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. As it does so, moisture in the atmosphere will be lifted, and cold air in place will yield a swath of snow into Tuesday night from the High Plains to the Corn Belt, Upper Mississippi Valley and northern Great Lakes.

MORE: Winter Storm Delphi (PHOTOS)

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