Area Forecast Discussion
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FXUS61 KPBZ 020206
Area Forecast Discussion
National Weather Service Pittsburgh PA
906 PM EST Thu Dec 1 2016
A trough of low pressure across the Great Lakes will keep clouds
and near seasonal temperatures across the area into the weekend.
.NEAR TERM /THROUGH FRIDAY/...
-- Changed Discussion --Main change was to add possibility of drizzle or freezing drizzle
to areas north of Pittsburgh and along the ridges...although it is
not expected to be particularly impactful or widespread. Models
and the 00Z sounding show that cloud top temperatures are hovering
near or just below -10C, which brings the presence of ice crystals
in those clouds into question. Can already see this occurring with
DZ reported at YNG during the past hour. However, forecast low
temperatures will hover around freezing and relatively warm
ground and road temperatures are still in place. Thus, do not
foresee much impact from the possibility of FZDZ at this time,
even if it technically occurs. Will not be issuing a headline at
this time, leaving open the possibility of one if impact or
coverage is more than currently anticipated. Otherwise, only
minor tweaks to sky/PoPs/temps were performed.
Winds will shift closer to due westerly by Friday, bringing a
slight increase in chances for snow showers. With a solid overcast
expected, temperatures will remain slightly below normal.
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.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
As winds shift to the northwest Friday night, coverage of snow
showers will slightly increase, but any snow accumulations Friday
night into Saturday should remain minimal. As the low moves east
late Saturday, any precipitation should come to an end. Although
some partial clearing is expected Saturday night, clouds will
increase once again on Sunday as the next systems approach from
the west. Have slowed down the arrival of precipitation, which
should generally keep the area dry during the day. Temperatures
will remain a few degrees below normal.
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Still a bit unsure about precipitation chances Sunday night into
Monday as long range models are showing that two system may
bracket the area to the north and south. Stuck with chance pops.
Models are in better consensus bringing precipitation in with low
pressure Monday night into Tuesday, and have gone with likely pops
during this time period. A bit of model uncertainty continues once
again for precipitation later in the week, with the GFS not
showing a potent low pressure system that the ECMWF has remained
consistent with for the last couple days on Thursday. Although
temperatures will be above normal Tuesday and Wednesday,
Thursday`s cold front will bring in the coldest air of the season
Thursday night into Friday.
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Cold advection will maintain ceilings at VFR / low MVFR levels
through the period. Some colder air aloft is expected to arrive
by Friday morning with a weak wave to help lower ceilings. With
low level flow shifting to W-NW on Friday, anticipate periodic
snow showers over the northern terminals.
Brief restrictions are possible in showers through the weekend
especially N of I 80 with broad upper troughing and cold W-NW