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Area forecast discussion 
National Weather Service Duluth Minnesota
1123 PM CST Wednesday Dec 17 2014

Update...
issued at 1018 PM CST Wednesday Dec 17 2014

Even though high pressure is building across the forecast area...a trough
remains over northwest WI to the twin ports at 04z. Clouds were
developing/spreading across northwest WI into the twin ports along this
trough. There were some high clouds over The Arrowhead and clear
skies elsewhere. Updated sky grids as a result and lowered min
temperatures a bit where the clear sky prevailed.

Update issued at 513 PM CST Wednesday Dec 17 2014

Dropped the headlines in northwest WI as the snow has ended. Still expect
a snow shower or two...but no accumulation. Rest of the forecast
unchanged.

&&

Short term...(this evening through thursday)
issued at 303 PM CST Wednesday Dec 17 2014

A ridge of high pressure was building across northern Minnesota
this afternoon resulting in partial clearing over north-central
Minnesota. Clouds had redeveloped from the Brainerd lakes into
northwest Wisconsin. Lake effect snow and associated clouds
continued along the South Shore. The ridge will shift farther east
overnight yielding a diminishing trend in cloud cover. Drier air
near-aloft will continue spreading southeast over Western Lake
Superior...allowing the lake effect snow to end this evening.
Temperatures tonight will trend cooler over northern and portions
of central Minnesota tonight as the result of the clearing
skies...while milder temperatures remain over northwest Wisconsin.
Thursday will be drier as the ridge axis advances east into
Wisconsin. High temperatures will nudge a few degrees warmer with
light winds.

Long term...(thursday night through wednesday)
issued at 303 PM CST Wednesday Dec 17 2014

There are growing concerns that a winter storm could affect the
Northland during the middle of next week...prime Holiday travel
time. Read towards the bottom for more information.

Thursday night...high pressure over the eastern forecast area will
provide another night of light winds and mostly to partly cloudy
skies. There will be increasing clouds from the west...but the lack
of cloud cover in the east could result in some fog. Added patchy
fog for late Thursday night in the far eastern area of northwest Wisconsin.

Friday through Sunday...there will be a weak upper level low
drifting east over southern Manitoba and northwest Ontario. Its trough will
move through the northern plains and then the Northland. Model
soundings indicate that the sustained low/middle level south-southwest flow will
result in increasing saturation and cloud cover. This could result
in snow flurries and very light snow accumulations over NE
Minnesota. Increased the overnight lows since the cloud cover should
bolster the temperatures.

Next week...the GFS and European model (ecmwf) are indicating an Alberta clipper will
move into the northern plains late Sunday and early Monday...then
stall over the upper Midwest late Monday and early Tuesday. The
Northland could see some snow with this clipper. The greater concern
is that the models are indicating a 140 to 150 knot jet in the
western US will dig a more potent wave into the Southern
Plains...which will then lift and merge with the Alberta clipper
over the central/eastern Great Lakes region by midday Wednesday.
This could form a very large and deep low pressure system near Lake
Huron by Wednesday evening or early Thursday. The GFS and European model (ecmwf) both
have the center of the low approaching 960 hpa. This could result in
significant snowfall over the Northland...especially over the
eastern forecast area. Colder air would likely move into the
northern plains and upper Midwest on the western side of this
system...which could result in heavy amounts of lake effect snow
over northwest Wisconsin and large waves over Lake Superior. The models
have the low slowly drifting northward into James Bay and far
western Quebec Thursday night and Friday...and showing middle/late week
cold snap for the Northland and upper Midwest. This storm is still
quite a ways a way...but we will need to provide a close watch on
run to run model trends and how this system could affect the
Northland.

&&

Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1123 PM CST Wednesday Dec 17 2014

A surface trough over northwest WI into the twin ports was the focus for MVFR
ceilings and a few flurries near dlh/hyr. Expect the MVFR ceilings to
prevail through the forecast. Elsewhere...VFR. MVFR ceilings arrive at
brd by 16z and hib/inl around 02z.

&&

Preliminary point temps/pops...
dlh 8 25 18 26 / 0 10 0 10
inl -1 21 13 26 / 0 0 0 20
brd 4 23 16 27 / 0 0 10 20
hyr 12 26 15 28 / 0 10 0 0
asx 15 26 16 29 / 10 10 0 0

&&

Dlh watches/warnings/advisories...
Minnesota...none.
WI...none.
Ls...none.

&&

$$

Update...gsf
short term...huyck
long term...grochocinski
aviation...gsf

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