Scientific Forecaster Discussion
fxus61 kctp 252308
Area forecast discussion
National Weather Service State College PA
708 PM EDT sun Aug 25 2019
dry weather and comfortable humidity continues through Monday.
Clouds and humidity will increase through midweek with spotty
light rain on Tuesday and scattered thunderstorms on Wednesday.
The second half of the week looks mainly dry with near to above
Near term /until 6 am Monday morning/...
fair weather cumulus already beginning to collapse as we
approach sunset. Radiational cooling under mostly clear skies
will likely yield patchy valley fog late tonight. Also, model
guidance continues to hint at low clouds developing over the
Laurel Highlands toward dawn, the result of an increasingly
moist southeast flow and orographic lift. Latest model blend
supports low temps mostly in the low to mid 50s.
Short term /6 am Monday morning through Monday night/...
ridging at the surface and aloft will result in another dry day
Monday. Model soundings indicate any morning low clouds or fog
will mix out by late morning, with a mix of sun and cumulus to
follow for the afternoon. Have leaned cooler than the nbm
and closer to the superblend/NAM guidance, which tend to perform
better in southeast flow scenarios.
Low clouds may expand over the area Monday night with models
again targeting areas to the east of the alleghenies into early
Long term /Tuesday through Sunday/...
models are in decent accord in bringing a cold front into the
County Warning Area for mid week. The system is made to degenerate as it moves
east and encounters unfavorable low level shear associated with
a sprawling offshore low. Showers will still be widespread with
mainly daytime chances for sct tstms, but overall quantitative precipitation forecast should
remain on the light-moderate side.
Dry weather will return for the end of the week. From there some
model timing differences arise with a cold front for the
weekend. The GFS/Canadian are in accord with this weak feature
sparking some new showers, while the European model (ecmwf) holds showers off
until Sunday. Given the low confidence, I used blended pops for
the Sat-sun timeframe.
Aviation /00z Monday through Friday/...
widespread VFR through late tonight. Low clouds and patchy fog
may result in some restrictions early Monday - but confidence
is low. Low level southeast flow pattern may plague the airspace
with sub-VFR cig restrictions into midweek.
Tue...am low cigs possible central and eastern airspace. Spotty
light rain possible.
Wed...am low cigs possible. Sct PM showers/T-storms.
Thu-Fri...no sig wx expected.