Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
107 am EDT Tuesday Sep 23 2014
dry weather can be expected for the remainder of the week while
initially cold temperatures slowly moderate.
Near term /until 6 am this morning/...
with 1215am update...made minimal changes to hourly temperature
trends...as well as pulling nearly all cloud cover as skies have
quickly cleared after sunset.
dry advection off the surface will continue for a while though resulting in a
dry hydrolapse adjacent to the surface. Temperatures are thus expected to
drop quickly after sunset and most of the area is expected to
experience lows in the upper 30s as residual surface moisture dews...or
frosts out. Patchy frost mention has been continued for those lower
elevations of the western and southern counties...while more widespread
frost is anticipated adjacent to the ridges as elevated valleys
may see middle/isolated low 30s. Those areas remain undr a frost advisory.
Short term /6 am this morning through Thursday/...
high pressure will continue to dominate the short term period as middle/upper level heights
rise across the Midwest. Some moisture is projected to creep up the
Appalachians for the latter half of the week...but a prognosticated lack
of forcing and ovrall subsidence should keep it from being a decisive
player in the forecast. As such...dry conditions were favored
through the week with temperatures rising a few degrees above the
Long term /Thursday night through Monday/...
temperatures are expected to remain from 5 to 10 degrees above the avgs into
early next week as upper ridge axis slides over the eastern Continental U.S.. European model (ecmwf)
continues to hint at a weak trough developing over the middle Atlantic
coast this weekend...but that solution is again out of phase with the
GFS. Persistence remains the prudent response and a dry forecast has
Aviation /05z Tuesday through Saturday/...
VFR conditions expected overnight outside of any local visibility
restrictions near area rivers.
Outlook.../Tuesday night through Saturday/...
building high pressure will result in VFR conditions the remainder
of the week and into the weekend.
Maryland...frost advisory until 9 am EDT this morning for mdz001.
PA...frost advisory until 9 am EDT this morning for paz074-076.
WV...frost advisory until 9 am EDT this morning for wvz023-041.