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fxus63 kdlh 191137 

Area forecast discussion
National Weather Service Duluth Minnesota
537 am CST Fri Jan 19 2018

Short term...(today through saturday)
issued at 326 am CST Fri Jan 19 2018

Today through Saturday will be quiet with warmer than normal
temperatures, with a weak upper level ridge over the area. A ridge
riding shortwave is moving out of Saskatchewan this morning and will
move into Ontario by this evening. This shortwave will not have
much of an effect on the forecast area, but may bring some showers
or flurries/sprinkles to the Iron Range on north from about mid
morning through the afternoon and early evening. Pops are very low
and little if any accumulation is expected. Another shortwave will
move along the top of the ridge for Saturday, but that feature is
much weaker and do not expect anything but an increase in cloud
cover for Saturday. Temperatures through the period to be above
normal, with highs today in the 35 to 40 range, though the extra
cloud cover will keep US in the 30 to 35 range for Saturday. Lows
in the 20s tonight put US well above normal, with our overnight low
at dlh warmer than the normal low temperature.

Long term...(saturday night through thursday)
issued at 326 am CST Fri Jan 19 2018

Still keeping a close eye on next winter storm that will begin to
affect the Northland Sunday evening.

The forecast period begin with a upper trough making landfall on the
West Coast then digging deep into the Desert Southwest. It
eventually closes off then moves east northeast across the Midwest
on Monday. In response a Lee low will develop over Colorado then
eject northeastward from The Four Corners region on Sunday. By
Sunday evening the surface low should be somewhere in the southeast
NE and northern Kansas vicinity with the warm front across Iowa and
central WI. With the strong warm air advection across the frontal
boundary, expect light snow to form north of the front Sunday
afternoon with the best chance closer to the front across northern
WI. As the low moves northeast into Iowa Sunday night the
precipitation will spread northward to cover northwestern WI and
into the Minnesota arrowhead. By this time the low will be nearly
vertically stacked and will support some very good snowfall rates
north of the front in the strong frontogenesis zone. At this time
there is still uncertainty where band of heaviest snow will be, but
the trend has been a shift to the south from the original axis
through Duluth. This puts northwest WI in the heaviest snow area.
But, pinpointing this area is tricky this far out and will continue
to monitor. The longer range models are still taking the low across
WI, with the European model (ecmwf) the most southern with the surface low center
forecast to move over the Milwaukee area while the GFS is taking a
more northern Route across the Door Peninsula with the Canadian
almost following suit. What we do know is that this storm will
generate strong east to northeast winds across Lake Superior and
make for a windy time late Sunday night and Monday, especially
closer to Lake Superior. The falling snow and the wind will also
make for low visibilities. Our first guess for snowfall amounts is 6-
12 inches across Pine County, Minnesota and all of northwest WI with much
lesser amounts over the northeast Minnesota. There will be a very sharp
snowfall gradient across the twin ports area to Aitkin with snowfall
amounts dropping off quickly to the northwest. Again, these snow
areas and amounts are a first guess and could change in the next few

Colder air will be advected south as the low moves away from the
Northland. This will set up a period of lake effect snow over
northern WI at least through mid week. Late next week another trough
is forecast to come ashore along the West Coast and bring another
low across the Midwest. This could bring another round of snow to
the Northland beginning Friday


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 530 am CST Fri Jan 19 2018

VFR conditions as of issuance time are expected to continue
through at least 00z. A brief period of low level wind shear to affect khib this
am, diminishing by 16z, with less shear at the other locations. A
weak front will move through the area and bring a few
sprinkles/flurries to kinl and khib in the 14z- 23z time range.
After 00z an area of MVFR stratus will flow into the area from the
north behind the front, moving into kinl, khib and possibly also
kdlh by 12z. For now do not expect any precipitation with this
stratus, though that may change.


Preliminary point temps/pops...
dlh 38 23 32 22 / 10 10 0 10
inl 39 23 30 14 / 20 10 0 0
brd 38 22 33 22 / 0 0 0 10
hyr 38 23 35 25 / 10 10 0 10
asx 40 26 35 24 / 10 10 0 10


Dlh watches/warnings/advisories...

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