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FXUS63 KFGF 150044

Area Forecast Discussion
National Weather Service Grand Forks ND
644 PM CST Thu Dec 14 2017

Issued at 644 PM CST Thu Dec 14 2017

Received some reports of freezing mist/drizzle up near Sarles that
was making roads slick. Other reports across the CWA indicate
light snow and roads are a mix of snow/ice/wet from todays precip
as well as previous events. Model soundings have the dendritic
growth layer saturating so think FZDZ should be transient and
short lived. Will include some mention in the grids and social
media but will leave off any headlines for now unless we start
getting more reports.


.SHORT TERM...(This evening through Friday)
Issued at 320 PM CST Thu Dec 14 2017

Expecting it to remain cloudy through the entire short term
period. Along with that, flurries or very light snow remain
possible throughout as well. Currently think more flurries will be
around early this evening. Then models indicate a little better 
chances for light snow will develop by mid evening, mainly over 
the Devils Lake region and northern Red River Valley. This 
activity may expand further south and east after midnight. 
However, really only talking about a dusting of snow with this. 
Next system still on track for Friday into Friday night. This next
system brings most of the area some light snow, but the main band
looks to be from the northern Red River Valley over toward 
Bemidji, where up to 2 to 3 inches of snow are possible. Lesser 
amounts are expected to the west. Wind speeds do not look very 
strong, which should lessen the impacts.

.LONG TERM...(Friday night through Thursday)
Issued at 320 PM CST Thu Dec 14 2017

Friday night and Saturday...Our northerly upper flow will 
transition to zonal heading into the weekend. As this occurs deep 
warm air advection snowfall should set up along a northwest-
southeast oriented baroclinic zone. The swath should cover a tract
from Devils Lake through the north and central valley to west 
central Minnesota with little or nothing over SE ND. Upper level 
support is lacking and there is the though that vigorous WAA will 
trim some of the available ice to the point of a possible mix of 
pcpn types, first over Devils Lake before propagating toward the 
valley later Fri night. Nevertheless, still favoring SN as main 
pcpn and sticking with the inherited 1 to 3 inch amounts. Impacts 
should be diminished by the lack of wind during this event. 
Forcing should be over by Saturday afternoon. 

Sunday through Thursday...Zonal flow will likely persist much of 
the week, with a stronger system likely affecting the region later
Mon and Mon night. The cyclone will likely move across Central 
Canada while the surface and upper trough swings through the 
forecast area dropping small snowfall amounts. But here the wind 
will be stronger behind the front, possibly creating blowing snow 
impacts. It appears that we'll go more NW flow midweek as temps 
drop to near and then below average values. Then a phasing trough 
could make things more interesting later in the week, with the 
early money on a more southern track, but we'll have to keep an 
eye on it with time. 


.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 644 PM CST Thu Dec 14 2017

Most areas are MVFR although a few have scattered out to VFR.
Think this will be short lived and all locations will be MVFR or
IFR by morning. Scattered snow showers moving through have brought
-SN to the central and eastern TAF sites at various times this
 evening, with the snow coming in an out but remaining above 6SM
 for the most part. A stronger band of snow will begin to move
 into the area tomorrow morning, spreading from northwest to
 southeast across the forecast area. Think the better chances for
 significant snow will be at the northern TAF sites. Visibilities
 in the snow band will be in the 3-5SM range early on with some 
 sites seeing 1-2SM late in the period. Light and variable winds 
 will steady out of the southeast, but remain below 12 kts. 




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