Scientific Forecaster Discussion
Area forecast discussion
National Weather Service State College PA
852 am EST Sat Dec 27 2014
high pressure will bring dry weather and mild afternoon
temperatures to the region today. A weak cold front will bring
scattered rain showers tonight and Sunday. The showers will
become mixed with a little snow across the western mountains by
Sunday morning. Colder and drier air will continue to filter into
the area next week with temperatures returning back to seasonal
normals...which will feel quite cold considering how warm it has
Near term /through tonight/...
9 am update...
temperatures should soon start to rise quickly...especially in the east where
the calm air had settled in early this morning. Full mixing will
be pretty shallow today...but 9h temperatures so mild that currently forecast
maxes are well on track.
high clouds will continue to gradually increase from the west
overnight...as the relatively flat upper level ridge axis over
the state slides to the middle Atlantic coast. Across the eastern
half of the County Warning Area skies have remained clear enough to permit enough
radiational cooling to drop temperatures into the upper 20s and
Mild air aloft combined with weak southerly flow and filtered sunshine
will bring another day of very warm temperatures for this late in
the year. Many areas across the eastern half of the County Warning Area will top
out above 50 degrees.
Short term /Sunday through Sunday night/...
clouds increase quickly tonight ahead of approaching frontal
system. Probability of precipitation will increase as well with rain showers accompanying
the frontal passage on Sunday. Most of the area will have their
warmest reading overnight or during the morning with falling
temperatures during the afternoon.
Long term /Monday through Friday/...
Sunday night and Monday begins with some uncertainty as to how the
frontal system exits the County Warning Area and whether a southern stream wave
that develops on the front moves far enough north to impact the
area. With cooling 850 temperatures...a mix of r/S is possible if this
wave does indeed develop and track far enough north. At this point
most of the guidance only gives the southeast zones a brief period of
mixed precipitation...and will continue with that as our forecast
at this time.
High pressure will build over the middle of the County by midweek
and slowly drift off the East Coast by the end of the
workweek...bringing an extended period of fair weather to the
forecast area. However...waves of colder air diving down from the
north will help temperatures will return to normal for the last week
Guidance is showing a more organized weather system developing by
next weekend...however there is much uncertainty in the
track given that this system is still a week out.
Aviation /14z Saturday through Wednesday/...
VFR conds will continue into Saturday as high pressure moves off
to our south. Some weak stratocu has formed over the northwest
mountains...however it will linger around MVFR ceilings but should
dissipate and clear by middle morning. Tonight into Sunday will be
the next chance for reduced conditions as a new frontal system
sags slowly south across the area. It should begin at bfd between
ooz and 06z. Then at jst between 06z to 09z...before affecting
aoo...ipt and unv 09z to 12z. MDT and lns should remain above
restrictions until Sunday morning. Expect mainly MVFR ceilings and
visibilities in light rain showers. IFR at bfd and jst is probable...but
mainly after 09z. Reducing conditions shouldn/T last to
long...with skies lifting by Sunday afternoon.
Sat nite-sun...MVFR/IFR with scattered rain or snow showers.