Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 180109

Area Forecast Discussion
National Weather Service Bismarck ND
709 PM CST Sat Feb 17 2018

Issued at 654 PM CST Sat Feb 17 2018

Latest radar and surface weather observations show light snow
slowly moving eastward into eastern Montana. This widespread area
of snow will continue moving eastward, making it into extreme western
North Dakota later this evening. Latest model guidance trends have
the storm system moving in a bit slower than previous model runs,
and the forecast has been updated to reflect that. There is still
some uncertainty as to how long light snow will persist over
central North Dakota tomorrow. Although the bulk of the heaviest
snow will likely be moving out of eastern North Dakota by 12 PM
CST tomorrow, there may be some lingering light snow into the
early afternoon hours across central North Dakota.


.SHORT TERM...(This evening through Sunday)
Issued at 145 PM CST Sat Feb 17 2018

Widespread, accumulating snow likely late tonight through tomorrow

A progressive, but potent upper level wave will swing through late
tonight/tomorrow. Frontogenetical forcing in the lower levels
will overlap lift in the upper levels. A saturated dendritic
growth zone, coupled with the strong lift suggest a fairly potent
band of snow will setup somewhere between Interstate 94 and the
International Border, with the Highway 2 corridor being most
likely at this time to see the higher snowfall amounts. There is
still uncertainty with regards to placement of this band even this
close to the event. The ECMWF is much further north than the GFS.
Ensembles place a general area of accumulation between I-94 and
the Canadian Border.

With widespread two to four inches and isolated higher amounts
likely, a Winter Weather Advisory was issued from I-94 north to
the International Border.

As the wave departs, breezy winds will cause the potential for
some patchy blowing snow Sunday afternoon, mainly across the
James River Valley, where reduced visibility will be possible in
open country.

The latest model runs indicate less of a threat for freezing
drizzle across the south and therefore elected to remove it from
the forecast.

.LONG TERM...(Sunday night through Saturday)
Issued at 145 PM CST Sat Feb 17 2018

On Monday, another shortwave will swing through the Northern
Plains, bringing the potential for some more light snow across
southern North Dakota. Behind this wave, another shot of arctic
air will bring the potential for dangerous wind chills across
western and central North Dakota through the middle of the week. A
slight warmup is possible by the end of the work week.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 654 PM CST Sat Feb 17 2018

Snow is expected to spread across the state later tonight through
at least Sunday morning. All terminals should experience MVFR
ceilings and visibilities in snow with patchy blowing snow. IFR
visibilities below 1 mile are possible at times, with the
greatest chance for KISN and KMOT. Some improvement is expected
later in the period as the area of snow diminishes from west to
east Sunday afternoon.


Winter Weather Advisory from midnight CST /11 PM MST/ tonight to
noon CST /11 AM MST/ Sunday for NDZ003>005-011>013-019>023-025-

Winter Weather Advisory until noon CST /11 AM MST/ Sunday for



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