Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
1048 am EDT Wednesday Jul 23 2014
a cold front will bring showers and thunderstorms to the area
Near term /until 6 PM this evening/...
late morning update was issued to adjust hourly trends of probability of precipitation and
temperatures...previous forecast of which was too conservative given the slow
frontal invasion and filtered sunshine.
Otherwise...the cold front will slide across the region today. Surface wind over
NE Ohio is already veering with passage of prefrontal trough...but
drier air should not be anticipated until tonight. Likely probability of precipitation were
adjusted southward with expectations of afternoon/early evening shortwave spprt and
higher instability via heating and surface dewpoints around 70f.
Short term /6 PM this evening through Friday/...
probability of precipitation diminishment from the northwest can be expected tonight...with lingering
slight...to chance numbers for areas S and east of pit through early
Thursday given the forecast of another shortwave across the stabilizing upper
Nevertheless...cooler and drier air will be advecting over the entire
region through the short term period.
Long term /Friday night through Tuesday/...
low confidence forecast for the beginning of the long term period.
Models exploring some different options with a shortwave trough
that will cross the area sometime on Saturday. This part of the
forecast will need to be refined once model run to run becomes
The next system will bring showers and storms to the area Sunday
and Monday and much cooler air for the end of the long term.
Aviation /15z Wednesday through Sunday/...
and approaching cold front will bring scattered showers and
storms from northwest to southeast across the region. For now MVFR
in showers with vicinity thunder still looks good and will need to be
refined in later terminals based on redevelopment as main line is
quickly weakening this morning. West to southwest wind near 10kt
ahead of the front will shift to the west northwest near 10kts with
frontal passage late this afternoon.
Outlook.../Wednesday through Sunday/...
the next chance for restrictions will come later Saturday and
Sunday as low pressure approaches.