Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 201139

Area Forecast Discussion
National Weather Service Green Bay WI
639 AM CDT Tue Mar 20 2018

Updated aviation portion for 12Z TAF issuance

.SHORT TERM...Today...Tonight...and Wednesday
Issued at 330 AM CDT Tue Mar 20 2018

High/mid clouds continued to gradually thicken over the region
early this morning, in advance of a weak upper trof. The trof is
expected to slowly move through the forecast area tonight into
Wednesday, but Hudson Bay high pressure is expected to feed dry
air into the region and hold off any precipitation. Northeast flow
was causing lake-enhanced clouds to develop near Lake Michigan
this morning, but radar was not showing any returns, despite
being in the more sensitive VCP 31. Thus, not real concerned about
lake-enhanced flurries today or tonight.

Under mostly cloudy skies, expect highs to reach the lower to
middle 30s today, with lows ranging from the single digits far
north central to the lower 20s southeast tonight. Partial
clearing and mixing through 825-800 mb should support highs in
the upper 30s and lower 40s on Wednesday.

.LONG TERM...Wednesday Night Through Monday
Issued at 330 AM CDT Tue Mar 20 2018

Generally dry weather can be expected for this part of the
forecast, though 00Z models start to show significant differences
by late this weekend.

A large surface high over Canada and an approaching mid level
ridge should keep the area dry through at least Friday. A surface
low is forecast to pass far enough to the south to keep
precipitation chances out of most of the area. There is a chance
for light snow late Friday night into Saturday morning, mainly in
central Wisconsin. Any snow should change to rain as temperatures
warm during the day. A change back to snow is expected Saturday
evening as precipitation chances end. The model blend had a
chance for rain and/or snow Sunday night into Monday morning. This
was left alone due to significant model differences by this time.
The GFS QPF had more than 2 tenths of an inch in parts of east
central Wisconsin while the ECMWF and Canadian were both dry
through Monday and had a system moving into the region about 24
hours later.

Temperatures are expected to be near or a little below normal
most days.

.AVIATION...for 12Z TAF Issuance
Issued at 624 AM CDT Tue Mar 20 2018

Lake-enhanced clouds with MVFR ceilings were affecting parts
of the Fox Valley and lakeshore areas this morning, though
observations were oscillating between SCT and BKN. Will carry
TEMPO groups for MVFR conditions for a few hours this morning.
There is a chance that lake-enhanced clouds will occur again late
tonight, so mentioned some low clouds at GRB/ATW and especially
MTW again. Otherwise expect middle and high clouds over the
region, with no VSBY restrictions.

Gusty northeast winds will continue in the Fox Valley and
lakeshore areas today.




SHORT TERM.....Kieckbusch
AVIATION.......Kieckbusch is the U.S. government's official web portal to all federal, state and local government web resources and services.