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Area forecast discussion
National Weather Service Grand Forks ND
320 am CST Fri Dec 9 2016

Short term...(today and tonight)
issued at 320 am CST Fri Dec 9 2016

Cloud cover, temperatures, and wind chills the main
concerns/challenges. 00z model guidance is in decent agreement
with synoptic features. Satellite imagery indicates clearing
across the Devils Lake basin with temperatures responding colder.
Wind Chill Advisory area seems reasonable for early this morning.

Surface ridging continues to build into the region today, and with
minimal mixing expect temperatures in the single digits
below/above zero (mainly dependent on morning lows with a 5f- 10f
rise expected).

Upstream observations indicate clear sky and temperatures less
than -20f under the sfc high. These observations are closest to
CMC guidance (which typically performs best in these conditions
with fresh snow cover and light winds/clear sky). Main question is
sky cover, so only trended toward the CMC solution. Wind chill
advisories may again be needed for Saturday morning.

Long term...(saturday through thursday)
issued at 320 am CST Fri Dec 9 2016

Saturday-Sunday...kind of a complicated upper level pattern and
models are having difficulty finding which upper level features
will be key. All guidance continues to indicate heaviest snow
south of the region. With that said, the European model (ecmwf) and GFS both have
resolved an upper level shortwave that will propagate through the
region later Saturday and Sunday. The CMC also has this feature
but is a bit quicker, while the NAM is the outlier not showing
this feature at all. However the details with timing play out,
given zonal flow aloft feel confident enough to say that a high
pop/low quantitative precipitation forecast scenario appears likely. Raised pops into the likely
category where the European model (ecmwf) and GFS both agree on measurable quantitative precipitation forecast.
Very high snow ratios expected (>20:1), which would lead to a
longer duration 1-3 inches by Sunday evening. Winds will be
relatively light, so the main impact should be limited to light
snow on roadways.

Monday-Thursday...this time frame will feature a 500mb low
dropping from northern Canada southeast toward James Bay. This
essentially leaves the forecast area in northwest flow aloft throughout the
entire period. Temperatures will likely see some day to day
fluctuation, but overall they will continue to remain cold. In this
type of pattern, cloud cover will play a factor in how cold these
temperatures can get. Wind speeds will also be a factor. At this
point, these wind speeds do not look to become very strong and
clouds are difficult to forecast out that far. However, if the winds
can stay steady enough, wind chills could be an issue during some
of the overnight periods. Otherwise, there could also be a few
periods with light snow or flurries, but no significant systems in
sight.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1153 PM CST Thu Dec 8 2016

Satellite and surface obs show a trailing edge of clouds from near
Sarles ND to Pleasant Lake ND and from Wimbledon ND to lamars ND.
Some holes were over Rox and northern Beltrami County. Trailing edge
was moving to the southeast at about 10 knots. MVFR conditions cover
the rest of the area. Some IFR conditions were over the southeast
zones. Expect MVFR conditions to slowly move into northwest Minnesota
overnight. Cigs should lift during the morning and should be VFR by
afternoon.

&&

Fgf watches/warnings/advisories...
ND...Wind Chill Advisory until noon CST today for ndz006-007-014-015-
024-026-028-029-038-054.

Minnesota...none.
&&

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