Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 170909

Area Forecast Discussion
National Weather Service Green Bay WI
409 AM CDT Fri Mar 17 2017

Forecast discussion for routine morning forecast issuance

.SHORT TERM...Today...Tonight...and Saturday
Issued at 408 AM CDT Fri Mar 17 2017

A band of snow and freezing rain continues to slowly track east
through the cwa early this morning. Despite very dry dew points
across the area, this band of mixed precipitation has steadily
marched eastward early this morning. County dispatch has reported
the wintry precipitation has caused some area roadways to become
ice covered and slippery in the current Winter Weather Advisory
area, therefore will expand the current headline northeast another
few counties to account for this band of mixed precipitation as
it tracks east. Further northeast the precipitation is not
expected to reach Florence, Marinette and Door counties until
after sunrise, thus minimizing the effects of liquid hitting the
roadways. Therefore will leave those counties out of the current
headlines. The Winter Weather Advisory itself will have an
expiration time of 900 am as sunrise is expected to warm area
roadways sufficiently to mitigate the icing effects by that time.

Warming temperatures will change the precipitation over to all
rain or drizzle later this morning and into the afternoon hours.
However freezing drizzle could return tonight and Saturday as
another shortwave tracks through the western Great Lakes with
soundings showing limited moisture in the low levels and abundant
mid level dry air which are expected to introduce quite a bit of
liquid precipitation in the column as overnight temperatures fall
below freezing.

.LONG TERM...Saturday Night Through Thursday
Issued at 408 AM CDT Fri Mar 17 2017

Forecast concerns for this period revolve around precip chances
Sunday night into Monday.  The latest ensemble means indicate that
rather low amplitude flow early in the period will become split this
week, leading to a rather large cyclone to move into the center of
the country by next Thu-Fri.  Have a slight preference for the ecmwf.

Saturday night through Sunday night...Scattered to broken low clouds
look to linger into Saturday evening but should be in the process of
clearing out as the surface ridge axis moves east across the state.
Could see a brief period of clear skies before mid and high clouds
increase relatively quickly late.  Sunday continues to look dry with
periods of broken mid and high clouds.  As a cold front moves into
Minnesota, forecast soundings point towards saturation occurring
below 775mb late in the afternoon into early in the evening across
region.  This should lead to an increasing chance of showers through
the evening into the early overnight with the passage of a cold
front. Temps should be warm enough for precip to fall as mostly
rain, but amounts look meager due to a lack of moisture and
subsidence aloft in the right front quad of a jet streak.  Chances
will be highest over eastern WI.

Rest of the forecast...The cold front will continue to march east on
Monday, but skies will likely remain partly to mostly cloudy behind
the front with some low clouds over eastern WI in the morning, and
mid and high clouds overhead in the afternoon.  These clouds will
depart Monday night into Tuesday with incoming Canadian high
pressure.  Temps will cool off to near or slightly below normal on
Tuesday through Wednesday.  The next chance of precip will ramp up
Thursday and Friday ahead of the next cyclone.

.AVIATION...for 06Z TAF Issuance
Issued at 1003 PM CDT Thu Mar 16 2017

Cigs will continue to lower overnight as mixed precipitation
moves into the area. A mix of mvfr and ifr cigs and vsbys
expected by Friday morning. Conditions expected to gradually
improve to a higher end MVFR or lower end VFR Friday mid afternoon
in the wake of the surface front. Scattered mvfr cigs due to snow
showers will return over northern Wisconsin with colder air
returning to the region.

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


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