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Area forecast discussion 
National Weather Service Green Bay WI
1052 PM CDT Friday Oct 31 2014

Updated aviation portion for 06z taf issuance

Short term...tonight and Saturday
issued at 331 PM CDT Friday Oct 31 2014

Winds and lake effect precipitation are the main concerns early in
the period...followed by temperatures.

The upper level trough that passed through Wisconsin overnight
continued to slowly move away from the state today...with a weak
ridge moving in during the evening on northerly flow aloft.

Surface high pressure to the west of the state was slowly making
its way to the east. Winds should taper off the rest of the
afternoon and during the evening due to the weakening surface
pressure gradient. The high is forecast to be centered over the
state by 12z Saturday so winds should be rather light from 06z to
12z Saturday...especially in north central Wisconsin.

Backing winds and warm advection at 850mb should bring an end to
lake effect precipitation in the area by this evening. Clouds in
the east may take a while to move out...as the ec had some high
925mb relative humidity values during the night across eastern Wisconsin. Gem-reg
cloud forecast from meteorological service of Canada showed clouds
clearing in central and north central Wisconsin late this
afternoon and early this evening...while clouds remain in the
Lakeshore counties until after midnight.

The clear skies and light winds across north central Wisconsin
later tonight...combined with fresh snow cover...should result in
rather cold lows tonight. Have trimmed a couple of degrees from
lows in that part of the state tonight...resulting in some single
digits. This still may not be cold enough for some parts of the
area.

Long term...Saturday night through Friday
issued at 331 PM CDT Friday Oct 31 2014

An upper ridge drifting over the region will provide dry
conditions for the rest of the weekend. Warm air advection on the backside will
provide moderating temperatures along with breezy conditions
Sunday afternoon. The air mass appears too dry for a precipitation
mention on Sunday into Sunday night with a warm front...but
clouds likely will be on the increase.

Next chance of showers pointing toward later Monday into early Tuesday
with the passage of a short wave and surface trough and weak cool
front. Slightly cooler air may produce a brief mix across the
north before the system pulls away late Monday night or Tuesday
morning. Models are starting to produce a swath of at least one
half inch across part of western Great Lake region...but will
focus on higher probability of precipitation over the southeast half of the forecast area
for now.

Nearly zonal flow expected through middle week...followed with a
trend to a gradually deepening upper trough over the Great Lakes.
Cold air advection pattern within this trough supports a shift to a mix over at
least the northern portion of the forecast area later in the week.

Will lower this Saturday night min temperatures a little across the far
north due to a snow cover may linger over this region...and
forecast clear skies. Otherwise seasonal temperatures return
Sunday into the first half of next week followed by cooler
temperatures later next week.
&&

Aviation...for 06z taf issuance
issued at 1052 PM CDT Friday Oct 31 2014

A cold northeast flow of air over the Great Lakes will
keep broken VFR ceilings between 3500 and 4500 feet across
northeast and east central Wisconsin through Saturday morning.
Elsewhere it should be mostly clear with patchy low clouds and fog
late tonight and early Saturday morning where snow is on the
ground north of Rhinelander. Saturday will be a nice flying day
with clearing skies and light surface winds.
&&

Grb watches/warnings/advisories...
none.
&&

$$

Short term.....Mg
long term......tdh
aviation.......rdm

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