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Area forecast discussion 
National Weather Service Green Bay WI
629 PM CST Friday Nov 28 2014

New information added to update section

Update...
issued at 626 PM CST Friday Nov 28 2014

Will be issuing a Freezing Rain Advisory for wood...Portage...
Waushara and Winnebago counties through 11 PM. This matches up
with current radar trends and warm layer aloft of +3 c or
greater for most of the evg. Patchy freezing drizzle may occur
farther north later tonight...but should not be as much of a
concern.

Update
issued at 547 PM CST Friday Nov 28 2014

Currently evaluating whether or not to issue a Freezing Rain Advisory
for our far SW counties. Radar already indicating that some sleet is
occurring near Wautoma...and there may be a brief period of freezing
rain SW of a line from mfi-osh this evg. Tough call as most roads
should already have been treated...and freezing rain is usually not as big
of a problem when it falls on top of snow. However...there have
been reports of bad Road conditions and cars sliding off roads south
of our forecast area. Will make a final decision within the next
half hour or so.
&&

Short term...tonight and Saturday
issued at 226 PM CST Friday Nov 28 2014

Ongoing light precipitation event and temperatures tomorrow are the main short-term
forecast issues to deal with this afternoon.

Periods of light snow continued across mainly the northestern 2/3 of the forecast
area this afternoon. The snow was occurring in isent lift regime associated
with backing upper flow...in combination with weak shortwaves riding east-southeast
across the area. The consensus of the models was that light precipitation would
continue into the evening. Stuck with fairly high probability of precipitation into the
evening...then tapered back. The snow may become more showery in
nature during the late afternoon and early evening as middle-levels
destabilize.

Warmer air working eastward during the night combined with a decr in
middle-level moisture may result in a loss of ice crystals seeding
lower clouds...and a change to fzdz as the main precipitation type. Quite a few
observations of fzdz were received from Minnesota during the day...even in
some locations where the thermal/moisture profiles seemed more
favorable for snow. So...transitioned the precipitation over to mainly fzdz
fw SW-NE overnight. It never takes much fzdz to make a mess of
travel...but with forcing waning by later in the night and fzdz
likely falling into the snow that accumulated today...felt having it
in the forecast and having a mention in the severe weather potential statement and now products would
be sufficient to handle the sitn. Temperatures should continue to slowly warm
overnight.

Any lingering precipitation by Sat should be fzdz...and be mainly across the
far N/NE. Warmer air will be pushing eastward from the plains...but the
main push of warm air is expected to surge through above strong low-
level inversion. Went with blend of guidance products weighted toward
the European model (ecmwf) and it/S MOS product. That put temperatures above fzg across the
area...but still in the 30s. Would need to have seen stronger
boundary layer winds and a more westerly component to the boundary
layer wind before considering taking temperatures above guidance.

Long term...Saturday night through Friday
issued at 226 PM CST Friday Nov 28 2014

Fairly quiet in the long term...with the biggest focus on a cold
front sweeping through the state on Sunday and then the bitterly
cold temperatures for the beginning of the week.

Lets focus on the good news first...there are no major storm
systems forecasted to effect the County Warning Area through the end of the week.
Zonal flow sets up across the Continental U.S. By midweek which will keep our
weather quiet. Some chances for precipitation are possible as weak
disturbances move through the mean flow...however models differ on
the timing and anything that could fall should remain light and
uneventful.

Unfortunately...the forecast doesnt have beautiful weather either.

After a quiet Saturday night with above normal low temperatures and some
light lake effect snow in Vilas...a cold front will sweep through
the state on Sunday. No precipitation is expected ahead of the
front...however temperatures behind it will be bitterly
cold. Temperatures will drop through the day on Sunday as high
pressure builds southeastward out of Canada. By 00z Monday...the
cold front will be east of the area and 850mb temperatures will be around
-15c over the County Warning Area. Sunday night will be cold...however slow
clearing of clouds will keep temperatures for plummeting. Did drop
lows a few degrees as model guidance continues to trend colder.

Northern Wisconsin will See Lake effect snow through the day on
Sunday before coming to an end Sunday night as high shifts east
and the flow off of Lake Superior becomes less favorable.

On Monday the Arctic high will be centered over the state. With
the cold airmass in place...many locations will struggle to get out
of the single digits in north central Wisconsin. Dropped high
temperatures here too per model guidance trends. Dry weather is expected
with clearing skies on Monday.

Monday night will be colder than Sunday night as there will be
less cloud cover. Much of the area could fall below zero.

After Monday night...models begin to differ in light precipitation
chances through the end of the week. It will depend on the timing
of disturbances that edge through the flattened synoptic
flow...and models always have issues with strength and timing of
these features. Some hints on the long range models that the flow
becomes amplified again Thursday or Friday..however didnt get
cute with precipitation chances for the second half of the week. The good
news is models all have temperatures rebounding midweek to more
normal values for the beginning of December.
&&

Aviation...for 00z taf issuance
issued at 547 PM CST Friday Nov 28 2014

Light snow will taper off over NE WI this evg...followed by
scattered light snow...sleet...freezing rain (mainly central WI
and the southern Fox valley) and freezing drizzle through about
midnight. Patchy freezing drizzle may linger into the overnight
hours. Expect mainly MVFR conditions after the steadier snow ends
this evg. Some improvement is anticipated on Saturday afternoon...
and possibly even some clearing.
&&

Grb watches/warnings/advisories...
Freezing Rain Advisory until 11 PM CST this evening for wiz035-
036-045-048.
&&

$$

Update.........Kieckbusch
short term.....Skowronski
long term......Allen
aviation.......kieckbusch

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