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Area forecast discussion 
National Weather Service Green Bay WI
550 PM CST Monday Jan 26 2015

Updated aviation portion for 00z taf issuance
and new information added to update section

issued at 545 PM CST Monday Jan 26 2015

Quick check with Wood County indicated roads just snow covered...
with no major travel problems reported. Will allow the advisory
to expire at 600 PM.

Short term...tonight and Tuesday
issued at 245 PM CST Monday Jan 26 2015

The latest rap analysis and satellite/radar imagery show a weakening
low pressure system moving south-southeast as it approaches far northwest
Wisconsin. Ahead of the low...modest warm advection and middle-level
fgen are contributing to a band of snow...but the best returns
appear to be exiting central Wisconsin early this afternoon. The
latest data show that the middle-level fgen will continue to weaken as
the best warm advection pulls should see only very light
snow or flurries for a period until better returns over Western Lake
Superior arrive. Still seeing observations at Marshfield and
Medford of freezing drizzle or unknown no plans to
change the advisory. Some possibility that it could get extended
into the evening...but no indications of freezing drizzle elsewhere
though. Snowfall accums and impacts remain the main forecast

Tonight...clipper low pressure will continue to weaken as it tracks
across far SW Wisconsin early this evening and into western
Illinois. Another area of light snow associated with warm advection
will move across north-central and eastern Wisconsin that will
prolong the light snow for much of the evening. The snow will
likely diminish over central Wisconsin by middle to late evening...but
saturation will remain deep enough for patchy freezing
left that possibility in the forecast on the western edge of the
precipitation. The highest accumulations will be over eastern Wisconsin
where a half inch or inch will likely fall. Light onshore flow from
southeast winds may locally boost totals higher over the Door Peninsula
from lake enhancement. Most guidance supports light precipitation
diminishing late tonight across the east...though flurries could
continue in the east due to the light onshore flow. Lows mainly
between 19-24 degrees.

Tuesday...because weak low level convergence will be
continuing...think overcast conditions will persist through much of
the morning hours. As Arctic high pressure tries to rebuild into
the region during the afternoon...should see the low overcast erode
from the west and also the east which will lead to increasing
sunshine. Highs will range from the upper 20s to lower 30s.

Long term...Tuesday night through Monday
issued at 245 PM CST Monday Jan 26 2015

A couple of weak upper troughs will approach from the west
Wednesday night and bring some light snow to the region. Not
much moisture available but there is pretty good low level warm
advection and convergence in northeast Wisconsin. Think we will
get 1 to 3 inches with the greatest amounts over door Marinette
and Florence and Forest counties.

Lake effect snow showers possible in northcentral Wisconsin
Wednesday afternoon and Wednesday night but accumulations should
be light. Dry and colder Friday and Saturday. An Arctic cold
front will approach the area Saturday night and Sunday and should
be able to produce some light snow as it moves across the area.
Monday should be quite cold with subzero highs possible in
northern Wisconsin.

Aviation...for 00z taf issuance
issued at 545 PM CST Monday Jan 26 2015

Although the system producing the snow will slowly shift off to
the southeast tonight...MVFR/IFR ceilings will linger in the moist cyclonic flow
remaining behind the departing system. Ceilings in central WI may even
drop into the LIFR category for a while overnight.

Grb watches/warnings/advisories...
Winter Weather Advisory until 6 PM CST this evening for wiz035.


short term.....Mpc
long term......rdm

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