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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
1214 PM CST Sat Feb 13 2016

Update...
issued at 1204 PM CST Sat Feb 13 2016

Aviation discussion for the 18z tafs has been updated below.

&&

Short term...(today and tonight)
issued at 340 am CST Sat Feb 13 2016

The short term concerns are morning wind chill headlines and
snow headlines for tonight.

High pressure ridge over western Minnesota will move slowly east during the
day. Winds have diminished or become light and variable over much
of the west and will trend that way into the morning east. Wind
Chill Advisory expires at 8 am...and is only marginal over
western central WI. Will let it ride for now.

The concern shifts to snow potential developing tonight over mainly
the Minnesota portion of the County Warning Area. Models continue to show trough moving
over the Pacific northwest this morning...diving to the southeast
over South Dakota later today and tonight. This spreads a shot of
snow into the southwest during the evening and to the Wisconsin
border through 12z Sunday. Forcing maximizes to the southwest by 06z
Sunday and then shifts off to the southeast. The upper trough
swings across southern Minnesota through Sunday...so it still looks like
much of the area will see some accumulating snow. Trend of the sref
and some deterministic models have shifted the main snow axis a bit
farther to the south. However...the 00z GFS continued its more
northern track...focusing along and south of the Minnesota River
Valley. The 03z sref indicated some Middle Range probabilities for 1
inch an hour snowfall rates over the far south as well...where the
dgz was maximized. We should see around 3 inches of snow fall over
the southwest through 12z Sunday. Perhaps an inch or two farther
east into east central Minnesota with additional accumulations into
Sunday morning. There will be a southeast wind as the system moves
in...and doesnt appear strong enough to generate widespread blizzard
conditions. We will see lower visibilities as the snow develops and
drifting snow is a good bet as the system moves through. We did
drop a Winter Weather Advisory on much of this region for tonight
and part of Sunday.

Long term...(sunday through friday)
issued at 340 am CST Sat Feb 13 2016

The snow will be ongoing Sunday morning across much of the
area...but by middle morning the forcing weakens further and snow
should be on the diminishing trend with only a chance of snow by
evening. Another couple inches are expected in spots Sunday.

After a dry Monday...the next system to watch continues to also
shift further south Monday night and Tuesday. It is becoming more
and more unlikely we will see much with this one as it tracks
southeast across the western Dakotas and into northern Missouri by
early Tuesday. The band of snow is favoring the weather forecast office fsd area...not
unusual this season with the city of Sioux Falls seeing almost
twice as much snow as the stc/msp/eau climate locations.

Another high will build south behind that system for midweek with
a shot of below normal temperatures.

The pattern will shift rather significantly for late week as the
ridge across the west shifts east to the central U.S. A large
system pushing onshore the coast of British Columbia and tracking
along the international border will draw much warmer temperatures
northward across the plains and into the middle Mississippi Valley.
Temperatures in the 70s are possible as far north as Interstate 80
Thursday and Friday...with snowpack modifying that airmass quickly
further north. The degree of moisture return is not too anomalous
with the Gulf being modified by a few preceding cold fronts...
but it will be enough to generate considerable cloudiness and
perhaps advection fog over the snowpack Friday. Temperatures were
increased to around 40...which should not be too difficult to
achieve considering we were in the 40s shortly after the last
winter storm 11 days ago.

&&

Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1204 PM CST Sat Feb 13 2016

VFR conditions through the rest of the afternoon...before far
western Minnesota sees the MVFR ceilings and -sn developing after 00z
tonight. Hi-res cams continue to indicate what the deterministic
models have been showing since yesterday...the heaviest quantitative precipitation forecast swath
from eastern North Dakota toward Iowa...clipping far western Minnesota.
Expect most of the area to see mainly MVFR type ceilings/visible overnight
and early Sunday. Rwf likely to see more sustained IFR and some
LIFR possible with 2 to 5 inches possible there.

Kmsp...the metropolitan looks to be on the eastern edge of the precipitation
shield...but still thinking 1-3 inches is possible. Heaviest snow
likely after 08z...weakening after 12z. Lingering light snow is
expected during the day on Sunday.

/Outlook for kmsp/
Sun night...MVFR with chance -sn. Wind south-southeast 15 knots.
Monday...MVFR/VFR ceilings. Wind west 10 knots.
Tuesday...MVFR/VFR with -sn possible. Wind northwest 10 knots.



&&

Mpx watches/warnings/advisories...
WI...none.
Minnesota...Winter Weather Advisory from 9 PM this evening to noon CST
Sunday for mnz047-054>057-064-065-067-073>076-082>085-
091>093.

&&

$$

Update...speed
short term...dwe
long term...borghoff
aviation...speed

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