Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
520 am EDT sun Aug 2 2015
mainly dry weather and seasonal temperatures today. A cold front
will bring showers Monday...with cooler temperatures into the
middle of the week.
Near term /through tonight/...
isolated showers across eastern Ohio continue to trend southeast.
Have adjusted slight chance probability of precipitation to latest radar trends. No other
changes and previous discussion follows.
Only a few middle and high clouds today with seasonal temperatures.
Small and weak shortwave diving southeast across Ohio this
morning producing a couple showers over north central Ohio...and
have added isolated showers across far southern counties before
sunrise this morning.
Southwest flow ahead of an approaching cold front Sunday will
give increasing high clouds...with temperatures in the lower to
middle 80s. Cold front will gradually approach tonight with
increasing clouds...increasing deep moisture...and a chance for
showers before daybreak mainly north and west of Pittsburgh.
Short term /Monday through Wednesday/...
front will gradually slide southeast across region during the day
Monday. Used a blend of the GFS/European model (ecmwf) for timing. Newest Storm Prediction Center
outlook puts much of region in a slight risk for severe...but this
will be dependent on how much low level instability can actually
be realized. Bulk shear near 40 kts is forecast by models...so
will mention in severe weather potential statement. Gradually cooler with drying behind
front Tuesday. Timing issues Wednesday with strong shortwave
moving east along stalled boundary south of region. Used a model
compromise to slowly increase shower chances during the day
Wednesday with higher probability of precipitation south. Temperatures Wednesday will
remain below average.
Long term /Wednesday night through Saturday/...
there is good agreement in the long term forecast as an upper
trough remains parked over the eastern US. Several waves riding
through the upper flow will maintain the chance for showers and
thunderstorms through the period...with overall better consensus
between the GFS and European model (ecmwf) than in the previous days runs. With the
trough prognosticated to deepen by next weekend...expect temperatures to
trend a few degrees cooler than seasonal averages in northerly flow.
Aviation /09z Sunday through Thursday/...
general VFR will continue as surface high slides to the east. Wind
gusts to 15kts will once again be possible in the afternoon.
Outlook...Sunday night through Thursday...
restriction potential will increase with the approach and passage of
a Monday cold front. VFR will then return until the next upper
disturbance approaches Thursday.