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Area forecast discussion 
National Weather Service Duluth Minnesota
634 am CST Friday Nov 28 2014

Short term...(today and tonight)
issued at 400 am CST Friday Nov 28 2014 elevated warm front...associated with a low in north
central Montana...will continue to slowly lift through the plains
and upper Midwest towards the Northland. This front and middle level
frontogenetical banding has brought snow to much of the southern
half of the forecast area this morning. The far southern forecast
area can expect the highest accumulations through this
afternoon...about 2 to 3 inches. The snow will gradually diminish
from west to east this afternoon. Earlier forecasts were calling
for potential sleet to develop later this afternoon as warmer
temperatures aloft move into the forecast area from the
south...but the latest model runs keep the threat of sleet just
south of the forecast area until this evening. Cancelled the
Winter Weather Advisory for the SW forecast area early since most
of the snow is over and sleet is no longer expected this
afternoon. Kept the advisory going for the south central and southeast
forecast area since the snow will continue with up to around 3
inches of accumulation. We might be able to cancel this advisory
by this afternoon if most of the snow has moved out of the area by

Tonight...there will continue to be warm air advection aloft as
the elevated warm front lifts through the Northland and the
surface low moves into the northern plains. Model soundings
indicate a transition from light snow to light sleet from south to
north. Much of the forecast area could see light ice accumulation
due to the sleet. While some models indicate a potential for
freezing rain...soundings suggest any falling precipitation should
refreeze in the very cold layer near the surface. Therefore...left
freezing rain/drizzle out of this forecast. We might need another
Winter Weather Advisory tonight for the light sleet. There will be
east to southeast flow over Western Lake Superior later tonight...and the
WRF models are suggesting the potential for up to a couple inches
of snow accumulation tonight before the transition to sleet.

Today will be 10 degrees colder than normal with highs in the
middle to upper teens. Temperatures will not fall much this
evening before being bolstered or rising later tonight due to the
warm air advection.

Long term...(saturday through thursday)
issued at 400 am CST Friday Nov 28 2014

A warm front associated with a 850 mb low in Canada...will lift
across the region and into Ontario Saturday. This will position
the Northland in the warm sector...with a layer of above freezing
temperatures aloft to support a period of sleet or freezing drizzle. At
this time...the main area of focus for light ice accumulations
will be across the Iron Range/arrowhead...near the warm
front/low...where latest NAM bufr profiles suggest the best
moisture and precipitable water values are expected to exceed a half inch. Winds
will remain easterly Saturday morning ahead of the cold
front...bringing a potential for slightly higher snow/ice amounts
values along the North Shore of Lake Superior...mainly east of

Saturday evening...a strong baroclinic zone/cold front will sweep
across the region...bringing a transition to northwest
winds...caa...and plummeting temperatures for the remainder of the
weekend. The coldest readings are on track to arrive Sunday
night/Monday morning as the h50 trough swings across Ontario and
over the Lake Superior region. The latest 00z runs of the
GFS/ecm/Gem bring the core of coldest air further south than the
past few runs and suggest 850 mb temperatures around negative 30s c dip into
the Borderland by Monday morning. This extremely cold air mass
will allow for steep lapse rates and gusty winds
overnight...potentially producing some very chilly wind chill
values in the negative 30 to 40 range by Monday morning. A Wind
Chill Advisory may be needed for portions or all of the Northland
Sunday night/Monday morning.

There will be a brief return to srly flow/warm air advection early in the
week...ahead of yet another clipper/cold front that tracks over
the region middle week.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 630 am CST Friday Nov 28 2014

Light snow or flurries will persist over the region this
morning...mainly affecting kbrd...kdlh...and khyr with periods of
MVFR ceilings. A warm front will lift into the forecast area this
afternoon...pushing into Ontario overnight. A period of a
snow/sleet/fzdz mix with very light ice accumulate possible is
expected to accompany the warm front across central Minnesota and
northern Wisconsin late today into the early evening...shifting
northward into the kinl and khib areas after 06z.


Preliminary point temps/pops...
dlh 17 16 32 12 / 80 40 20 10
inl 15 10 27 2 / 50 70 60 20
brd 18 16 34 9 / 60 20 10 10
hyr 18 16 35 18 / 90 20 10 10
asx 19 15 36 21 / 80 30 20 20


Dlh watches/warnings/advisories...
Minnesota...Winter Weather Advisory until 4 PM CST this afternoon for mnz038.

WI...Winter Weather Advisory until 4 PM CST this afternoon for



Short term...grochocinski
long term...graning

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