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Area forecast discussion 
National Weather Service Grand Forks ND
928 PM CST Sat Nov 28 2015

issued at 928 PM CST Sat Nov 28 2015

Dropped lows a few degrees in the Devils Lake basin based on
latest trends. The latest hrrr model runs tend to favor fog south
of Devils Lake a little further. Updated fog extent slightly
further southward into northwest Griggs County. Fog is not out of the
question for the Grand Forks area according to the hrrr.
However...the new NAM MOS guidance removed mention of fog. Will
continue to keep fog north and west of ground fog.

Update issued at 547 PM CST Sat Nov 28 2015

Freshened up a few forecast grids with this update. Changed sky
grids based on latest trends and model data. All in all...the
forecast looks on track. Will keep an eye on northern Minnesota fog
potential tonight as latest hrrr model has some patchy fog across
parts of the north. May need to expand fog from northern ND and
far northwest Minnesota further east to Baudette. Will consider with next


Short term...(this evening through Sunday night)
issued at 300 PM CST Sat Nov 28 2015

Main forecast challenge will be upcoming snow event across the
southern forecast area later Monday into Tuesday. Confidence still on the low
side as models continue to differ on surface low track affecting
snow amounts and how far north snow shield will get. There has
been a model trend of delaying arrival of snow. Models also seem
to be trending a bit south this run with exception of the European model (ecmwf)
which is farthest north and this run an outlier. With plenty of
uncertainty will lean heavily towards consistency and National

Upper low will begin to shift into the central/northern rockies
overnight. An impulse rotating around the low later tonight should
spread band of middle/upper level clouds into the south half half of
the forecast area. Farther north under sky clear and light winds areas of fog are
possible and added to forecast. Warmest temperatures overnight
will be across the south under cloud cover.

Models have backed off on quantitative precipitation forecast Sunday with lobe rotating around
upper low so maintained dry forecast. Will actually see some
cooler spreading from S-north during the day and more clouds may limit
temperatures a couple degrees cooler than today but still close to

Continued increase in cloud cover will keep temperatures mainly in
the teens Sunday night.

Long term...(monday through saturday)
issued at 300 PM CST Sat Nov 28 2015

Models are in agreement in slowing up arrival of snow to southern
parts of the region with favored potential now more towards late
afternoon/evening. Did maintain some low probability of precipitation in the afternoon but
confidence low. Temperatures are still expected to range a few
degrees either side of freezing.

Best snow potential will be overnight Monday. Highest probability of precipitation still
expected along the ND/South Dakota Minnesota border regions with moderate
accumulations possible. With model uncertainty no headlines
planned at this point.

Snow should shift into the southeast forecast area Tuesday diminishing from west to east
during the afternoon.

Expect diminishing snow showers...cloudiness and northwest winds on
Tuesday a low pressure system moves away from the area
and into the western Great Lakes.

European model (ecmwf) and GFS guidance appears fairly consistent on a move towards
more dominant 500 mb ridging over the northern plains through the middle to
late week period. Wednesday into Thursday we can expect a seasonably
mild and dry northwest to westerly flow pattern aloft...with deep
southwesterly flow aloft developing over the area on Friday as
troffing digs deeply into the intermountain west. Late Friday into
Saturday could be our next chance for scattered light /mixed/
precipitation as a cutoff low reforms over The Four Corners area and
the 500 mb trough axis passes over the northern plains. Temperatures
throughout the middle to late week period should remain well above
seasonal normals.


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 547 PM CST Sat Nov 28 2015

Added hint of low ceilings/visible in kdvl for late tonight. Hrrr model
continues to have patchy low ceilings/visible tonight across the kdvl
area...but keeps the fog north of kgfk. NAM MOS guidance does hint
at low IFR ceilings for kgfk...and will watch closely for possible
amendment. Onset wouldn't be until after midnight local time. Less
of a chance at ktvf...but still possible. Otherwise...expect light
winds and high clouds moving in from the south tonight with
approaching low pressure.


Fgf watches/warnings/advisories...


short term...voelker
long term...gust/voelker

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