Area Forecast Discussion
Issued by NWS Grand Forks, ND

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FXUS63 KFGF 141838

Area Forecast Discussion
National Weather Service Grand Forks ND
1238 PM CST Wed Feb 14 2018

Issued at 1230 PM CST Wed Feb 14 2018

With stronger sun temperatures in some areas are warming more than
forecast so upped temps by 5 deg or so in WC MN into the Bemidji
area where temps will be in the 40s today.


.SHORT TERM...(Today through Thursday)
Issued at 357 AM CST Wed Feb 14 2018

Snow and blowing snow with the cold front tonight/tomorrow morning
will be the main challenges for the period.

Mild temperatures and quiet weather will continue for much of
today as near zonal flow become southwesterly ahead of the next
upper trough. The surface low tracking across southern Canada will
allow southwest winds to shift from the southwest to the west, and
eventually northwest late in the day. There will be thermal
ridging for much of the day ahead of tonight`s cold front and with
a mild start we should manage to climb into the 30s across the CWA
even with increasing clouds. Some 40s are even possible in the
southwest counties.

Tonight, the cold front will begin to move into the northwestern
counties during the evening, pushing further south and east
throughout the night. The models are in fairly good agreement on
snow along and behind the cold front. There is some weak 850mb
frontogenesis along with the synoptic scale lift, but at this
point banding potential looks minor and think the 00Z NAM is
overdone on snow amounts. Other deterministic models have
accumulations in the 1 to 3 inch range around the Highway 2
corridor and this seems reasonable. Think the higher impact will
be increasing north winds behind the front and blowing snow. 925mb
winds are not horrible, generally around 25 to 30 kts but there
will be a decent amount of cold air advection which often boosts
our winds above guidance. Have sustained winds late tonight into
Thursday morning in the 15 to 20 kt range but that may have to be
bumped up a bit later on. Patchy to areas of blowing snow will be
possible with the winds and falling snow. Temps will be dropping
with the passage of the cold front, and Thursday could see some
non-diurnal curves. Some advisory level wind chills will be
possible again in the north Thursday morning.

.LONG TERM...(Thursday night through Tuesday)
Issued at 357 AM CST Wed Feb 14 2018

00Z Fri-12Z Sat

Northwest flow aloft continues across the region for the most part.
Split flow continues over North America with northern stream over
southern Canada/Northern Plains and the southern stream over the
Pacific Northwest to the Central plains.

Upper level low pressure over Hudson Bay will have short waves
rotate around the system. Arctic air will have already dumped into
the Northern Plains Thu night. The arctic air will shift east Fri.
Another short wave will approach the area Fri night and cooler air
will again move out of Canada but not as cold as Thursdays cold


Longwave upper level low pressure system remains over northern
Hudson Bay and does weaken through the period. Longwave upper level
ridge remains over the Caribbean and from AK south to the eastern
Pacific with little change. The ECMWF was the faster solution
through the period.

Flow aloft becomes more split as an upper trough over the Pacific
Northwest on Sat drops into the Desert Southwest. Flow transitions
to southwest flow aloft by Mon and Tue. However continued short
waves rotating around northern system will allow arctic air to edge
into the area yet on Mon and Tue.

High temperatures for Sat were decreased by one to three degrees.
Highs for Sun, Mon, and Tue were decreased by one or two degrees
from yesterdays forecast package.


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1230 PM CST Wed Feb 14 2018

VFR thru the early evening...then as the winds turn north-
northwest behind a cold front expect a sharp drop into low end
MVFR and possibly IFR cigs in the colder air behind the front
overnight into Thursday morning as it spreads from northwest to
southeast. Increasing north winds too with gusts in the 30-35 kt
range in the RRV later tonight/early Thu. Vsby reduction in light
snow and blowing snow expected as well as light snow spread south
and east. Timed front and low cloud/snow arrival in TAFs.




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