Scientific Forecaster Discussion
fxus61 kpbz 151818
Area forecast discussion
National Weather Service Pittsburgh PA
118 PM EST Fri Nov 15 2019
dry conditions and below normal temperatures are expected into
early next week.
Near term /through tonight/...
dry and relatively cool conditions are expected today in advance of a
weak cold front. Latest visible satellite shows a narrow swath of
cloud cover through cincy/Columbus/new philly/Oil City, as pre-
frontal moisture remains trapped under the inversion. These clouds
will continue eroding with mixing. Farther north, a more expansive
swath of cloud cover is located north of I-80. While some erosion is
expected, increasing lower-level moisture should allow these to
linger through later fropa.
The front will sag southwards across the area Friday
evening/overnight. Precipitation chances will be low due to limited
moisture and upper support. However, cross sections and forecast
soundings indicate a saturated boundary layer (sfc to 3-4kft) by the
evening, aided by northwest flow off of the lake. With no cloud ice
present, some patchy freezing drizzle is not out of the question with
weak lift ahead of the front during the evening.
Short term /Saturday through Sunday night/...
high pressure will build back in on Saturday and expect limited
cloud coverage by the afternoon as winds aloft veer east.
Temperatures are expected to remain 10 to 15 degrees below average.
Saturday/Saturday night will be the coolest of the period before a
gradual warming trend begins on Sunday.
Long term /Monday through Thursday/...
ridging should maintain dry weather heading into next week before
unsettled conditions return. Overall there is good agreement with the
idea of broad troughing being the dominant feature in the extended,
but confidence is relatively low in the details. The first in a
series of shortwaves is currently progged to cross the region later
on Monday and Tuesday...with potential lake enhanced shower activity
lingering into Wednesday across northern zones. The next low pressure
system will impact the region later Thursday and Friday.
A gradual warming trend is expected through the period, with
temperatures returning to near average levels by mid week.
Aviation /18z Friday through Wednesday/...
Fkl will continue to struggle to reach VFR as the leading edge of a
cold front moves south off of Lake Erie. Sites elsewhere shall
maintain VFR conditions for the next few hours as high pressure over
the southern Ohio River valley persists.
A weak cold front will move through the region early this evening.A
lack of deep lift will prevent precipitation development. However,
there may be enough low-level moisture trapped beneath the Post-
frontal to create MVFR cigs for a brief period late tonight for a
number of sites.
Building high pressure over northern New York early Saturday morning
shall clear skies quickly, VFR conditions is expected to return and
continue into Sunday.
Restrictions may return Monday as a new system moves over the Great