Area Forecast Discussion
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FXUS61 KPBZ 070009
Area Forecast Discussion
National Weather Service Pittsburgh PA
709 PM EST Tue Dec 6 2016
Low pressure is expected to spread precipitation across the
region through early tonight. A Thursday cold front will return
snow shower chances and much colder temperatures for the end of
the week and into the weekend.
.NEAR TERM /THROUGH WEDNESDAY/...
Precipitation dissipating quickly from west to east and expect
this trend to continue through the evening hours. In addition to
the decaying precipitation, seeing a surge of warmer air at the
surface, especially over Ohio and Northern West Virginia. The
evaporation of rain is due to the fact that the inland surface
low, responsible for today`s activity, is phasing toward the
coast and the main surface low near the Chesapeake Bay will soon
take over. The push of warmer air is the last of the warm air
advection around the inland low, as surface winds swing to the
south and southwest. This final surge of warmer air will likely
end soon with the loss of the inland low. For this update, have
removed PoPs faster and also adjusted temperatures to more closely
represent current conditions and those overnight.
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
Lingering low level moisture over the eastern zones may cause
light precipitation early Wednesday. Otherwise, dry weather is
forecast for as surface high pressure builds across the region
The next cold front is still expected to cross on
Thursday, bringing the coldest air of the season so far. Have
increased PoPs for snow showers behind the front in the
developing mid-level trough. Latest guidance shows favorable lake
enhancement snow to develop mostly over the the north for a short
period of time. After the initial onslaught of the cold front and
blustery snow showers late Thursday, inversion heights will
gradually lower and decrease the snow accumulation rate by late
Friday. Nonetheless, stagnant low level moisture and lowering
dendritic growth zone is expected to keep snow chances lasting
through the start of the weekend, especially over the higher
Temperatures will lower to below normal values by the end of the
period and wind chill values are expected to decrease to near
.LONG TERM /SATURDAY THROUGH TUESDAY/...
The cold-supporting upper trough over the Eastern CONUS is
progged to fill rapidly early next week as another low develops
toward the Great Lakes. Flow over the Upper Ohio will thus
deamplify and temperature moderate back toward the seasonal
Best precip chances look to be on Sunday night and into Monday as
that Great Lakes low drags a front across the region. With the
low-center forecast well north of the region, precip timing will
depend on eventual frontal progress. Superblend guidance was
used for long term forecast construction.
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --IFR cig restrictions look likely to persist through the night
despite building high pressure with ample low-level moisture and
cooler air moving in aloft. TAFs were constructed with a nod to
all short-term guidance which shows improvement to low IFR
shortly after midnight but may opt to amend and extend IFR cigs
to mid-morning and improvement to VFR to mid-afternoon if rapid
update models and upstream trends support the idea.
Periodic restrictions are likely for the rest of the week as a
strong cold front sweeps the region.
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MD...Winter Storm Warning until midnight EST tonight FOR MDZ001.
PA...Winter Storm Warning until midnight EST tonight FOR PAZ074-076.
WV...Winter Weather Advisory until 10 PM EST this evening FOR