Mesoscale Discussion 2064

Issued

Dec 27, 2021, 6:56 AM CST (12:56 UTC)

Expired

Dec 27, 2021, 1:00 PM CST

In force

6 hr

Issued by

the Storm Prediction Center

Concerning

Blizzard

County Cook County, MN

The Duluth radar (KDLH), 78 km from the middle of the area, began a volume at 12:57 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

643 
ACUS11 KWNS 271256
SWOMCD
SPC MCD 271256 
MNZ000-WIZ000-271900-

Mesoscale Discussion 2064
NWS Storm Prediction Center Norman OK
0656 AM CST Mon Dec 27 2021

Areas affected...Portions of the MN Arrowhead/North Shore

Concerning...Blizzard 

Valid 271256Z - 271900Z

SUMMARY...Blizzard conditions appear probable through the rest of
the morning, with heavy/blowing snow and strong wind gusts greatly
reducing visibilities.

DISCUSSION...Recent surface observations show an occluded low near
the intersection of the ND/SD/MN borders. A shortwave trough
embedded within a broad swath of strong west-southwesterly mid-level
flow will continue to advance northeastward across northern MN/WI
this morning. The primary band of ongoing moderate to heavy snow
over northern MN will continue to shift northward across the MN
Arrowhead over the next several hours. Snowfall rates of 1-2 inches
per hour may occur within the strongest portions of the band, as
large-scale ascent associated with the shortwave trough will likely
help to maintain the snow band through the rest of the morning. An
enhanced surface pressure gradient exists between the occluded low
and high pressure centered over Ontario/Quebec. Strong
east-southeasterly winds, with gusts close to or above 35 mph,
appear likely to occur along/near the lakeshore this morning. These
winds will lead to greatly reduced visibilities of 1/4 of a mile or
less, and blowing/drifting snow. Some localized lake-effect
enhancement to snowfall rates may also occur along the North Shore
with a somewhat favorable fetch off of Lake Superior. This
combination of moderate to heavy/blowing snow, strong wind gusts,
and reduced visibilities should support near-blizzard to blizzard
conditions through the rest of the morning and continuing into the
early afternoon as the snow band gradually shifts northward.

..Gleason.. 12/27/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...DLH...

LAT...LON   46709247 46889286 46979266 46969233 47109196 47549135
            47919075 48128979 48018939 47828975 47629052 47149136
            46669226 46709247

Mesoscale Discussions in Minnesota, 2021Every mesoscale discussion in 2021

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.