Area Forecast Discussion
Issued by NWS State College, PA
FXUS61 KCTP 190330
Area Forecast Discussion
National Weather Service State College PA
1030 PM EST Sat Feb 18 2017
An extended period of mild, spring-like weather with above
normal temperatures is expected through the end of next week.
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
The evening water vapor loop is showing two features of interest
to central Pa this evening. The first is an upper low tracking
across the southeast states. Radar trends and near term model
guidance indicate the northern edge of showers associated with
this system could graze southern Pa overnight. Based on latest
HRRR, will maintain a low chance of measurable rain south of the
turnpike and west of Chambersburg. Second feature of interest
is approaching shortwave near Lk Superior this evening, which
will help push a weak back door cold front into Pa on Sunday.
Skies will range from mostly clear across northern Pa overnight,
to mostly cloudy across the south. An active westerly breeze
should hold temps up tonight over most of the area. Readings at
dawn expected to range from just the upper 30s north to mid 40s
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
Upper low and associated threat of showers should have passed
east of the region by 12Z Sunday. However, based on upslope flow
and nearly saturated soundings below 850mb, can`t rule out a bit
of drizzle over Somerset Co to start the day.
A weak back door cold front will deliver slightly cooler air,
but it will still be much warmer than normal. GEFS mean 850mb
temps about 2-4C cooler than today, likely translating to maxes
from around 50F over the northern tier, to the low and mid 60s
in the southern valleys. Model soundings suggest Sunday could
dawn a bit gloomy over the NW Mtns/Laurels with low level
moisture/upslope flow beneath inversion resulting in low clouds.
However, SREF probability data strongly suggests these low
clouds mix out by midday, resulting in mostly sunny skies across
the entire region for the afternoon.
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
The mild temperatures will continue through the extended
forecast as no cold air push is in sight. High temperatures in
general will be 10 to 20 degrees above normal with min
temperatures mainly above freezing.
a rather strong ridge builds in for early next week. Surface
ridge axis splitting the region will bring a bit of northerly/
northeast flow to eastern sections, suppressing temps a bit (but
still remaining well above average).
Weak system slides by to the north Tue night, and brings quick
chance for showers. Flow turns SW by Wed as temps rebound.
Pattern becomes more amplified late week as a system over the
central plains deepens and lifts into the Great Lakes. Clouds
will increase late week, with warm front lifting through Thu
into Fri - bringing increasing rain chances heading into the
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
00Z TAFS sent.
Dewpoints are quite low. Fcst dewpoints not expected to be
real high, and are often fcst too high by guidance. Thus
hard to see much in the way of fog or lower clouds for
Mon...VFR/No sig wx.
Tue-Thu...Sub-VFR psbl with chance of rain showers.
SHORT TERM...Fitzgerald/La Corte