Scientific Forecaster Discussion
fxus61 kpbz 192116
Area forecast discussion
National Weather Service Pittsburgh PA
416 PM EST sun Nov 19 2017
snow showers will diminish after midnight as the upper low moves
east. Dry and seasonal conditions are expected through midweek
before another cold front crosses.
Near term /through Monday/...
periods of snow will continue with sufficient lift from a
passing shortwave and strong cold advection through midnight.
Saturation through the snow growth zone will provide for a brief
period of efficient snowfall production, which could produce 2-3
inches of snow north of I-80 and in the WV/Maryland mountains.
Considering the short window and the borderline amounts, will
opt not to issue a Winter Weather Advisory at this time.
Shortwave will depart tonight, though NW flow will likely keep
some snow shower activity into the early morning before upper
level and surface high pressure builds overhead. The
aforementioned high pressure will help to shunt moisture below
efficient snow growth, thus, with minimal accumulation expected
after midnight. Cloud cover will start to diminish, but wind
will remain elevated enough to keep radiative cooling at a
Dry conditions are expected Monday with some moderation in
temperature due to sunshine and warm advection.
Short term /Monday night through Wednesday/...
high pressure will remain in control through Tuesday, with highs
getting closer to seasonal norms ahead of an approaching cold
front, progged for passage Tuesday night. The models have been
hinting to a slightly more amplified shortwave passage, but this
would still keep moist of the lift focused over the northern
half of the region. Kept pops rather consistent for now, with
adjustments needed as guidance comes more in line with a
Temperatures will cool back down - and run about 10 degrees
below average Wednesday.
Long term /Wednesday night through Sunday/...
broad troughing pattern will remain in place through the weekend
with fast moving systems progged Friday and Saturday. Similar
to Wednesday, most of the lift remains situated north so other
than some continued colder than average temperatures, pops were
kept rather low.
Aviation /21z Sunday through Friday/...
scattered to numerous snow showers will continue into the
evening hours. Expect general MVFR with LCL IFR in decent snow
cells. Sfc wind has diminished, but gusts to around 20kt can
be expected during the eve.
Improvement is forecast on Monday with building high pressure.
restriction potential returns with a Tue cold front and subsequent
upper troughing through mid week.