Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
830 am EDT Friday Oct 24 2014
mainly dry weather and seasonal temperatures for the weekend. A
warm up into the 70s is expected early next week before a cold
front impacts the region Wednesday.
Near term /through tonight/...
with 830am update...tweaked hourly temperature trends...but no
other changes were needed.
Early morning update to again adjust sky grids for stratus that
has expanded a bit before daybreak north and east of Pittsburgh.
With cirrus quickly moving into region this may delay mixing
somewhat so have kept more overcast/broken skies across the east
into middle morning. Where skies have remained clear very patchy fog
has developed...but this should lift quickly and have not
mentioned. No other changes.
Stubborn area of stratus from Oil City to Indiana and down the
ridges should mix out by middle morning as northwest flow in the
boundary layer relaxes. Mainly thin cirrus will then overspread
the region as a weak trough aloft crosses the region.
Temperatures a blend of model MOS.
Tonight middle and high clouds will be increasing as a somewhat
stronger shortwave approaches. Temperatures tonight near seasonal
Short term /Saturday through Monday/...
shortwave crosses region Saturday with very limited moisture. Only
isolated showers at best. Warm advection ahead of system will push
temperatures into the low and middle 60s. Drier and a bit cooler
temperatures behind system Sunday as high pressure builds east
with breezy northwest winds.
Long term /Monday night through Thursday/...
upper ridging across the eastern Continental U.S. Will begin to shift east Tuesday. This will
allow for the approach and passage of a middle weak...weakening shortwave and it/S
associated surface cold front. Timing specifics and amount of upper spprt remain in
qn so only forecast chance probability of precipitation at this time. High pressure is prognosticated Thursday before genl
upper trofg sets up by lt weak. With operational model differences...
preferred an ensemble/wpc solution throughout the period. Well above average temperatures Erly
in the weak will be replaced by seasonably cool levels after frontal passage.
Aviation /13z Friday through Tuesday/...
areas of low MVFR and IFR St is expd to affect ports north and east of pit
through Erly morning where moisture is trapped under an inversion. In
addn...patchy IFR fog will continue until just after sunrise across Ohio and the
WV Panhandle. Elsewhere...VFR conds are expd into tonight under high
pressure...though VFR SC is epxd to increase overnight ahead of an approaching weak
Outlook.../Saturday through Tuesday/...
brief rstrns are possible for northwest PA as the weak cold front crosses Sat.