Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 300350

Area Forecast Discussion
National Weather Service Green Bay WI
1050 PM CDT Wed Mar 29 2017

Updated aviation portion for 06Z TAF issuance

.SHORT TERM...Tonight and Thursday
Issued at 254 PM CDT Wed Mar 29 2017

Mostly cloudy skies prevailed across the region this afternoon.
Temperatures ranged from the upper 30s near the Lake Michigan
shoreline to the upper 40s across the far north where the cloud
cover was not as thick.

Main concern for tonight will be snowfall totals across portions
of central and east-central Wisconsin. Many complicating factors
to deal with including drier air advecting in from the east,
boundary and ground temperatures, and precipitation intensity and
qpf amounts. The 12z ECMWF has backed off on the heavier qpf
amounts across the Fox Valley and lakeshore region. Surface and
road temperatures should be a few degrees above freezing
overnight. With road and air temperatures slightly above freezing,
will need more intense precipitation to get snow to accumulate. At
this time, think an inch or two of snow is possible from Wisconsin
Rapids east to Appleton to Kewaunee, with lower totals to the
north and south. If a strong east-west band of precipitation can
set up for a period of time over the same area, locally higher
snowfall amounts are possible in this region. Also, the far north
is expected to get little or no precipitation with this system.

A mix of rain/snow should change over to mainly rain by late
morning on Thursday as temperatures warm into the upper 30s to
lower 40s. The warmest readings will be across the far north.

.LONG TERM...Thursday Night Through Wednesday
Issued at 254 PM CDT Wed Mar 29 2017

Precipitation type Thursday night, a generally dry weekend and the
track and precipitation trends with two significant low pressure
systems next week, are the main forecast highlights.

Low pressure tracking into the Great Lakes will continue to bring
gusty northeast winds and precipitation to most of the forecast
area Thursday night. RH timesections show a lack of mid-level
moisture and ice crystals through the night, so precipitation
type should be mainly rain or freezing rain, depending on surface
temperatures. Have kept temperatures a little above freezing in
the Fox Valley and lakeshore areas, so anticipating mainly rain
there. Any ice accumulations that occur farther northwest should
be light. Lingering precipitation should exit our southeast
counties Friday morning.

High pressure will arrive for the weekend, bringing primarily
dry weather to the region. Clouds will be on the increase Saturday
night into Sunday, and a few light showers could arrive Sunday

Low pressure will develop in the Southern Plains Sunday night and
track northeast Monday and Monday night. The GFS and GEFS take the
low into the northern Ohio Valley, while the ECMWF takes if
farther south, through Tennessee. The eventual track will
determine whether or not this only has a glancing blow on the
forecast area, but the best chances should be in southern
counties. Temperatures look warm enough for mainly rain.

Another low develops in the Central Plains on Tuesday and
tracks into central IL on Wednesday. The models are in better
agreement with the track of this system, and suggest that most
of GRB CWA should see at least light precipitation, with the
highest pops again in the south. The primary precipitation type
should be rain.

.AVIATION...for 06Z TAF Issuance
Issued at 1049 PM CDT Wed Mar 29 2017

ceilings and visibilities will fall to IFR roughly
south of a Wausau to Green Bay line tonight as light rain and
snow moves in from the west. IFR conditions will likely continue
Thursday with continued light rain or snow. MVFR or VFR
conditions are expected further north with little precipitation.



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