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Area forecast discussion...updated 
National Weather Service Duluth Minnesota
736 PM CST sun Dec 28 2014

issued at 736 PM CST sun Dec 28 2014

Lowered min temperatures to reflect current trends.


Short term...(this evening through monday)
issued at 251 PM CST sun Dec 28 2014

Much colder through middle-week following a cold front which moved
through the Northland this morning. Behind this cold front an
anomalously strong Arctic high pressure will move south from
Alberta into the northern rockies and northern High Plains early
this week. This will lead to northwesterly flow across the region
through mid-week. Lake effect snow showers will be possible along
the South Shore of Lake Superior today through tomorrow...though
confidence is below average.

Today...skies were clearing through the morning as the colder and
drier air moved in from the north behind a cold front. Some stubborn
stratus held on in parts of the Iron Range as of 1 PM
CST sunny skies were prevailing across almost all of northern
Minnesota. In northwest Wisconsin clouds were clearing in most
locations except for along northern portions of
Bayfield...Iron...and Ashland counties due to bands of lake effect
clouds/snow showers. This cloud cover was not very persistent as
cloud streaks wavered in the low level flow...and spotters reported
being able to see blue skies most of the time even while under a
burst of snow. With the push of colder and drier air throughout the
afternoon expect the lake-effect clouds to diminish for the the time
being and elsewhere temperatures were begin to drop. Highs in the
single digits north of Highway 2 in northern Minnesota...elsewhere in
the teens to near 20. Light northwesterly winds throughout the day.

Tonight...temperatures dropping below zero for the first time since
Dec 1st for Duluth and many locations outside of the international
border region. Clear skies and light winds. Lake effect snow showers
along the South Shore will decrease in the evening due to dry air
entrainment...but ramp back up again towards sunrise as low level
winds better align to reduce directional shear and allow for lake
effect bands to develop/intensify.

Monday...sunny and cold with high temperatures in the single digits
above zero...about 15 degrees below normal. The exception to the
sunny skies will again be along the South Shore of Lake Superior
where lake effect clouds/snow showers will lead to up to an inch or
two of snowfall in a few spots by the end of the day. Most locations
will just see a coating of fluff...with the higher terrain of Iron
and Ashland counties being the focus for most of the measurable

Long term...(monday night through sunday)
issued at 251 PM CST sun Dec 28 2014

Considerably different flow pattern and weather regime during the
extended period from what we have experienced for much of the past
month..with temperatures and sensible weather resembling something much
closer to seasonal norms as we remain in primarily northwest/west-northwest flow
aloft..with low level Arctic air mainly in place across the

By Monday evening..Arctic high pressure should be firmly in control
of the weather across the Northland with 850 temperatures below -20c. This
should lead to one of the coldest morning of the winter season..
with widespread low temperatures Tuesday morning in the minus teens with some
of the favored locations in interior northern Minnesota dropping
well into the 20s below zero. Winds do not look to be particularly
strong..but should be of sufficient strength to prompt the need for
wind chill advisories across parts of the Duluth County Warning Area Monday night
through middle morning Tuesday. Northwest low level flow normally would be
favorable for some lake effect snow on the South Shore..but ambient
upstream airmass appears to be extremely dry in the low levels and
this appears to be a significant limiting factor. There will still
likely be some snow showers with some light accums..but we do not
anticipate anything too terribly significant at this point.

Weak wave will slide southeastward toward the area Tuesday night/Wed..which may
bring low chances for some light snow. More importantly to sensible
weather..the increase in clouds and onset of weak low level warm
advection will likely lead to lows occurring before midnight..with
steady/slowly rising temperatures thereafter. The exception will be over
parts of northwest Wisconsin where the far southeast part of the Duluth County Warning Area will
likely experience the coldest temperatures Wednesday morning where the longest
period of light winds and clear skies will exist on top of somewhat
deeper and more fresh snowpack.

The weak disturbance Tuesday night/Wednesday will be followed by another brief
reinforcing shot of Arctic air before a better chance of light snow
affects the region late in the week with a somewhat stronger and
better organized warm advection pattern.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 548 PM CST sun Dec 28 2014

A prolonged period of VFR conditions will continue tonight through
Monday afternoon. Drier air will continue streaming into the
region near the surface and aloft resulting in clear skies
overnight. Winds may become gusty beginning Monday morning...but
peak winds of less than 20 knots are anticipated. With continuing
cold air advection...weak instability may develop Monday leading
to areas of scattered stratocumulus and a potential for snow flurries.


Preliminary point temps/pops...
dlh -9 5 -10 0 / 0 0 10 0
inl -16 0 -14 -6 / 0 0 0 0
brd -6 5 -9 1 / 0 0 0 0
hyr -6 7 -9 3 / 0 10 10 0
asx 2 9 -2 4 / 20 20 20 10


Dlh watches/warnings/advisories...


short term...jjm
long term...Miller

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