Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 230946

Area Forecast Discussion
National Weather Service Green Bay WI
346 AM CST Fri Feb 23 2018

Forecast discussion for routine morning forecast issuance

.SHORT TERM...Today...Tonight...and Saturday
Issued at 345 AM CST Fri Feb 23 2018

The combination of an strong upper jet at 500mb and
low level warm advection was producing mixed precipitation across
the region at 09z. There was a lull in the activity during the
late evening and early morning hours, and now there will be a few
hours of steadier precipitation before it ends from southwest to
northeast shorty after sunrise. There is potential for a tenth of
an inch or more of ice across parts of central and east central
Wisconsin with a couple inches of additional snow in the north.

West winds will bring mild and somewhat drier air this afternoon,
with temperatures rising above freezing in most places. Partial
clearing is expected tonight, with the coldest temperatures in the
north where there is fresh snow on the ground. Lows will be within
a few degrees of normal in most places. Clouds will increase
Saturday as the next system approaches. Low level dry air will
probably keep any rain or snow away until Saturday night. Highs
Saturday will be close to normal.

.LONG TERM...Saturday Night Through Thursday
Issued at 345 AM CST Fri Feb 23 2018

Flow aloft is forecast to be out of the southwest for the weekend
and much of next week. This will result in warmer than normal
temperatures and occasional storm systems ejecting out of the
southwest trough and approaching the region.

The main concern during this part of the forecast is the system
that will impact the area Saturday night and Sunday morning.

The 00Z versions of the NAM/GFS/ECMWF/Canadian were much more
consistent than they were the previous couple of days. The GFS
still had the strongest surface low but its track was similar to
those of the other models. This system will bring mainly snow to
north central Wisconsin, with more of a rain, wintry mix or
freezing rain event farther to the south and east. It appears that
parts of north central Wisconsin will receive advisory criteria
snow, and possibly even warning criteria, but will wait for the
winter weather advisory that is currently in effect to expire
before issuing any new headlines. Ice accumulations from the
system are forecast to be 0.1 inch or less.

A system is forecast to pass north of the state during the early
part of the upcoming work week, but the next chance for
precipitation should hold off until Tuesday night. Warm advection
to the northeast of a surface low and a weak mid level short wave
passing through the area will bring precipitation chances back to
central and eastern Wisconsin. Rain will gradually change to snow
as the boundary layer cools during the night. There is another
chance for precipitation late Wednesday night and Thursday ahead
of an approaching surface system and mid level trough. This should
start as snow but rain or a mix of rain and snow is expected later
on Thursday as temperatures warm.

Expect high temperatures to be mostly in the 30s to middle 40s
and lows generally in the 20s.

.AVIATION...for 06Z TAF Issuance
Issued at 825 PM CST Thu Feb 22 2018

A rapid deterioration to low-end MVFR or IFR conditions is
expected in the next several hours as a band of snow lifts into
the forecast area. The snow will change to mixed precipitation,
especially over central and east-central Wisconsin. The east will
probably further transition to just -RA/DZ by late tonight. LLWS
will also develop. Precipitation will diminish and end Friday
morning, but low ceilings will probably linger well into the

Winter Weather Advisory until 9 AM CST this morning for WIZ005-


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