Significant blizzard to impact High Plains/Northern Plains

"There is high confidence that a major winter storm will affect a large part of the central U.S. Wednesday into Thursday. Severe blizzard conditions are expected in some areas. You risk becoming stranded if you attempt to travel through these conditions."-NOAA's NWS Weather Prediction Center

"A strong spring snowstorm is expected to develop across the central to northern Great Plains on Wednesday and Thursday. This system will likely bring snow to most areas both days. There is a potential for very heavy snow to fall across portions of the area. However, there still remains a lot of uncertainty with this storm, so specific details are still being worked out. The potential for seeing totals of 6 to 12 inches of snow is increasing across portions of western and central South Dakota. There may also be a period of freezing rain on Wednesday across south central South Dakota, which may produce light to moderate ice accumulations. Strong northwest winds are expected with this system, which will result in significant blowing and drifting of snow. Travel may become hazardous to impossible." -NWS Rapid City, SD

Wind gusts (in knots) for Wednesday as the Low deepens

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
1249 AM EDT Mon Mar 11 2019

Valid 12Z Mon Mar 11 2019 - 12Z Wed Mar 13 2019

...Heavy snow expected in the Colorado Rockies Monday & Tuesday...

...Severe weather and heavy rainfall across the Southern Plains Tuesday &
Wednesday...

...Wind driven snow for portions of the central and northern Plains
Wednesday into Wednesday night...

Snows persist across the portions of the central Rockies and Great Basin
through Monday night as an occluded low moves out of the subtropical
Pacific and jumps northeastward into the Intermountain West.  Portions of
Colorado are expected to receive up to 10-20 inches of new snowfall Monday
and Tuesday.  A strengthening system to its northwest, responsible for its
ejection, brings a new round of coastal rains to the Pacific Northwest
Monday night into Tuesday, with interior snows expected near and behind
the system's cold front.  With time, this system merges in with the
deepening cyclone developing in the Colorado High Plains which greatly
increases snow storm potential across Colorado.  Temperatures across much
of the West and into the Plains should be below to well below normal with
expansive surface high pressure across the Central U.S. and the Pacific
system moving into the Southwest.

"WPC is monitoring a low pressure system currently located off the coast of Baja California. This system is forecast to track across northern Mexico into the southern Rockies before intensifying rapidly over the central High Plains on Wednesday. Potential exists for significant amounts of wintry precipitation to develop from the central Rockies into the northern Plains Wednesday into Thursday as the intense storm tracks northeastward through the central Plains." -NOAA's NWS Weather Prediction Center

Ahead of the systems impacting the West, a stationary front across the
Gulf Coast states and into the Southern Plains brings the promise of
showers and thunderstorms in the forecast on Monday and into Tuesday.  As
the low in the subtropical Pacific enters the Southwest by Tuesday,
showers and thunderstorms increase in coverage across the Southern Plains.
Atmospheric conditions could be favorable to support potentially heavy
rainfall and severe weather, especially late Tuesday afternoon into
Wednesday.  Both WPC and SPC have highlighted parts of this region within
a slight risk for flash flooding and severe thunderstorms, respectively,
from Tuesday into early Wednesday. This system is forecast to consolidate
into a significant storm by Wednesday morning as it organizes in southeast
Colorado, bringing wind driven snow to portions of northeast Colorado on
Wednesday and into the central and northern Plains Wednesday night. 
Temperatures across the Upper Midwest are expected to moderate enough to
support rainfall over an area with a deep snow pack which could accelerate
snow melt Wednesday night.

In the East, near or above normal temperatures on Monday should moderate
by Tuesday as the Central U.S. high pressure area expands eastward.  Snows
across the Great Lakes and New England slowly decrease in coverage and
intensity as cold, cyclonic flow slowly diminishes Monday into Tuesday.

Roth/Santorelli

Wednesday evening depiction of precipitation, fronts and low pressure centers. Graphic by the National Weather Service's Weather Prediction Center