Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 261116

Area Forecast Discussion
National Weather Service Green Bay WI
516 AM CST Sun Feb 26 2017

Updated aviation portion for 12Z TAF issuance

.SHORT TERM...Today...Tonight...and Monday
Issued at 257 AM CST Sun Feb 26 2017

Light snow showers early this morning and today the primary forecast
issue through monday.

Warm air return over the cold ground producing light snow showers
over north central and central Wisconsin early this morning.
Radar shows these weak returns working over the forecast area
this morning. Snow showers were more numerous near DLH with the
weak short wave trough and frontal system. This frontal system
slides over northern Wisconsin today where higher snow shower
chances expected. Will also continue snow chances over most of the
area through mid afternoon due to steep mid level lapse rates.
Higher total total values in the lower 50s toward 18z before
tapering off from west to east later afternoon as the short wave
trough pulls away.

The weak surface boundary stalls over the central part of the
state this evening with a surface high pressure ridge building
into the area overnight. A few progs linger light pcpn along or
northeast of this boundary this evening. Will keep a diminishing
chc of snow showers across the northeast this evening as the
short wave trough departs eastward. Not confident conditions will
set up any fog for tonight at this time.

What is left of the weak boundary Monday morning is lifted north
as a weak warm front as upper heights build ahead of the next
system approaching the area. Warmer temps expected on Monday.

.LONG TERM...Monday Night Through Saturday
Issued at 257 AM CST Sun Feb 26 2017

A weak surface ridge should help to keep the forecast area dry
through Monday evening before precipitation chances return ahead
of an approaching surface system and some mid level short wave
energy. Snow can be expected across the northwest half of the
area, with a wintry mix to the southeast. The wintry mix, and
then rain, will spread across the forecast area overnight through
midday Tuesday in warm advection.

Rain is expected to slowly change back to snow from north to
south on Tuesday night as cold advection kicks in with the
departure of the surface system. A mid level trough is expected to
bring additional snow shower chances on Wednesday.

Generally no more than slight chances for precipitation through
the rest of the forecast period as a mid level ridge approaches.
North central Wisconsin will be the exception with chances for
lake effect snow showers into Friday.

Much warmer than normal temperatures are in store for Tuesday, but
a cooling trend is expected through the end of the work week as
colder air behind the departing surface system enters the area.
Highs on Friday should be around 5 degrees below normal. Strong
warm advection in return flow behind a departing surface high
will bring much warmer than normal temperatures back for

.AVIATION...for 12Z TAF Issuance
Issued at 516 AM CST Sun Feb 26 2017

Clouds will lower to a high end mvfr cigs or lower end vfr today
which will continue into tonight. The mvfr cigs will mainly be
associated with mvfr vsbys due to snow showers. The combination of
a weak front dropping into northern Wisconsin and an unstable air
mass, a few of the snow showers may briefly be moderate to heavy
with ifr conditions.



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