Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 120256 AAC

Area Forecast Discussion...UPDATED
National Weather Service Green Bay WI
856 PM CST Sat Nov 11 2017

New Information added to update section

Issued at 855 PM CST Sat Nov 11 2017

Area radars show the primary region of freezing drizzle or drizzle
departing southeastward over Manitowoc County. Canceled the
winter weather advisory. Scattered slippery roads will linger
tonight with temperatures just below the freezing mark this

Issued at 735 PM CST Sat Nov 11 2017

At 730 pm, radar suggests the back edge of the freezing drizzle
and light freezing rain extended from around Oshkosh to Kaukauna
to Kewaunee. Areas northwest of this line will likely not see any
more light freezing precipitation. Areas southeast of this line
can expect the light freezing type pcpn to linger this evening.
Will try to let the the entire advisory expire at 10 pm to account
for any remaining slippery roads. Web cams showed plenty of wet
roads and air temperatures were still just below freezing.

Issued at 621 PM CST Sat Nov 11 2017

Freezing drizzle becoming more of a problem this evening with
pockets of light freezing rain at times. Anticipate this will
wind down this evening but slippery roads will linger until
treated since temperatures will be near the freezing mark. Ice
starting to collect on some objects and since an early season
event, will issue a short term winter weather advisory for
freezing drizzle.

.SHORT TERM...Tonight and Sunday
Issued at 236 PM CST Sat Nov 11 2017

Snow that moved across much of the area today was mainly in
eastern and parts of central Wisconsin at 20Z, and continued to
push eastward as a mid level trough passed north of the state.
Plenty of low level moisture and some lift behind the departing
snow resulted in areas of freezing drizzle. 12Z model time/height
plots showed weak or no lift across most of the area by 00Z so
any freezing drizzle should come to an end by then in most of the
forecast area. Snow may linger into the evening across eastern
Wisconsin before the trough departs and a surface ridge begins to
build into the state.

Another mid level trough and surface low are forecast to pass
south of the area on Sunday. Have kept the forecast dry for
now, but it is possible that precipitation associated with the
system could impact the far southeast part of the forecast area.
Highs should be near or above freezing on Sunday.

.LONG TERM...Sunday Night Through Saturday
Issued at 236 PM CST Sat Nov 11 2017

High pressure will bring dry conditions Sunday night through
Monday night. A weak short-wave and jet streak will pass through
the region Monday night, but a lack of significant lift or deep
saturation should prevent precipitation development.

Strong return flow and associated WAA will bring a chance of light
rain or drizzle on Tuesday. Rain chances will increase Tuesday
night as a cold front and short-wave trof move into the region.
The rain should end from west to east Wednesday morning as the
cold front exits the forecast area. A brief mix of rain/snow is
possible northwest early in the day.

High pressure will bring another brief period of dry weather
Wednesday night into Thursday.

Forecast confidence is lower on days 6/7 (Fri/Sat), as models
exhibit timing differences with a phasing low pressure system that
is expected to rapidly deepen to our east. The GFS is faster than
the ECMWF, but otherwise trends are somewhat similar. Aside from
a period of mixed precipitation changing to snow, there is
potential for strong northwest winds as the low deepens and pulls
out. Will mention a possibility of gale force gusts in the
Hazardous Weather Outlook for our marine areas.

.AVIATION...for 00Z TAF Issuance
Issued at 425 PM CST Sat Nov 11 2017

A band of Freezing drizzle will linger over parts of east central
Wisconsin this evening, which includes Taf sites GRB, ATW and
MTW. Otherwise mainly MVFR ceilings will prevail tonight into
Sunday morning. Some improvement to VFR levels can be expected
later Sunday morning as high pressure settles into the area.



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