Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 172358

Area Forecast Discussion
National Weather Service Duluth MN
558 PM CST Wed Jan 17 2018

Issued at 558 PM CST Wed Jan 17 2018

Please see the 00Z Aviation Discussion below.


.SHORT TERM...(This evening through Thursday)
Issued at 404 PM CST Wed Jan 17 2018

At 4 PM, sunny skies prevailed across the Northland. Temperatures
had jumped into the middle 30s in a few locations along the North
Shore, namely Two Harbors and Silver Bay. Temperatures elsewhere
ranged from the mid 20s to around 30 with southwest winds.

The focus for tonight continues to be the vigorous, compact,
shortwave moving into the region from the northwest. Water vapor
imagery shows this feature well across south central Canada. The
models are generally in agreement in bringing this system very
quickly through the Northland, with the best consensus on bringing
a quick shot of precipitation to the region later tonight and
Thursday morning. While the system will be quite strong, it will
be rather moisture-starved and fast moving. This should mean snow
accumulations of generally an inch or less, along with some patchy
freezing drizzle at times as well.

The system will move out of the region on Thursday, leaving
partial sunshine for the afternoon. High temperatures are expected
to be even warmer on Thursday, with most locations settling into
the 30s for daytime highs.

.LONG TERM...(Thursday night through Wednesday)
Issued at 404 PM CST Wed Jan 17 2018

The late week warmup for the Northland still looks to be on track.
The last push of warm air with 850 hPa temperatures of 8 to 11
degrees will arrive Thursday night into Friday. This will result in
surface temperatures in the upper 30s for most of the CWA. Some
western areas may reach 40 early Friday afternoon before a cold
front pushes through during the late afternoon hours. This clipper
system won`t have too much effect on the CWA, other than bringing in
some cooler air. There may be some freezing drizzle or sleet Friday
morning along the International Border, with perhaps some light
drizzle in the same areas ahead of the cold front, but most of the
activity will end up north of the border. Highs Saturday will still
be on the mild side with readings in the low to middle 30s.

The main concern in the long range continues to be the snow
potential for Sunday into Monday. The GFS, Euro and GEM continue to
show a Colorado Low moving from the Central Plains and into the
western Great Lakes and today`s 12z runs are no exception. This
latest run has shifted the storm track slightly to the north,
putting more of the Northland into the area of potential snowfall.
This northward shift also shifts the potential heaviest snowfall
into northwestern Wisconsin back into east-central and southwestern
Minnesota. However, more changes are expected until the system moves
onshore and enters into the upper-air network Friday evening.
Regardless, parts of the forecast area will see snow with this
system and the potential is there for heavier amounts. Another shot
of colder air will arrive behind this system, but temperatures look
to be pretty close to seasonal normals.


.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 558 PM CST Wed Jan 17 2018

The main concern over the next six hours is low level wind shear
at all terminals due to light winds at the surface, and strong
winds aloft. There may be a brief break in the low level wind
shear late tonight as the winds aloft weaken. However, there will
be a second round of wind shear into the morning hours as winds
increase due to the low moving in from the northwest.

Ceilings will gradually lower to 1500-4000 ft as the low moves in
from the northwest late tonight. Expect INL and HIB to see MVFR
ceilings develop as snow spreads in after 06Z per the GFS/NAM.
Precipitation will remain on the periphery of DLH/HIB, and should
stay well to the northeast of BRD. Forecast soundings show that
freezing drizzle is possible as precipitation wraps up, due to the
loss of ice aloft. After precipitation ends, high pressure will
build in and gradually scatter out ceilings.


DLH  18  33  22  37 /  40  60   0  10
INL  17  33  20  39 /  60  60  10  30
BRD  18  35  22  40 /  10  10   0   0
HYR  15  33  20  39 /  20  20   0   0
ASX  18  33  22  40 /  40  50   0  10




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