Scientific Forecaster Discussion
fxus61 kpbz 180225
Area forecast discussion
National Weather Service Pittsburgh PA
925 PM EST Wed Jan 17 2018
high pressure should maintain dry weather through Saturday. The
next chance for rain is expected with a warm front Saturday
night and Sunday.
Near term /until 6 am Thursday morning/...
the remaining stratocu and flurries should continue to slowly
erode tonight as an upper trough exits, low level ridging
builds, and winds back to the SW. A few mid and high clouds
could cross the area overnight in warm advection. Should see
most temperatures become steady after the initial drop this
evening as the warm advection begins and winds remain sufficient
to preclude widespread decoupling. The wind and cold
temperatures should result in advisory level wind chills in the
higher terrain of WV and Maryland. Maintained the Wind Chill Advisory
there. Otherwise, lows in the single digits are expected, with
some of the coldest locations just below zero.
Short term /6 am Thursday morning through Saturday/...
a return to zonal flow or even ridging aloft will be temporarily
stunted by a fast moving shortwave trough cruising through the
Great Lakes Thursday. Even still, temperature moderation is
expected Thursday falling just shy of average values. Otherwise,
this quick trough should result in little more than additional
clouds across northern zones.
Heights will then begin to build further into Friday as a very
broad ridge slides eastward. Further temperature moderation is
expected, and should begin to do work on the remaining snowpack.
Drying and warming will carry through Saturday as trough digs
into the western Continental U.S. And we maintain zonal flow aloft.
Eventually this flow will stream moisture back into the area
from the west, and an increase in cloud cover is expected.
Long term /Saturday night through Wednesday/...
warm advection will strengthen through the weekend ahead of the
next system approaching from the west with temperatures climbing
to around 15 degrees above normal on average across the region.
Increasing cloud coverage on Sunday as moisture advection ramps
up...with light precipitation possible.
Latest model consensus progs frontal passage on Monday
afternoon...with the best chance for rain along and ahead of
the cold front. Temperatures on Tuesday will lower back to near
normal behind the front.
Aviation /02z Thursday through Monday/...
the back edge of the stratocumulus deck that has plagued most
sites from fkl-pit-mgw and points to the east is starting to
erode from the west. With increasing SW flow by morning, this
will continue to be the case with most sites likely going VFR
and clearing out in the next few hours. Mgw will likely be the
last to clear. Gusty SW winds will develop on Thursday, but all
sites will remain clear. Fries
restriction potential returns over the weekend with approaching
Maryland...Wind Chill Advisory until 9 am EST Thursday for mdz001.
WV...Wind Chill Advisory until 9 am EST Thursday for wvz512>514.