Area Forecast Discussion
Issued by NWS State College, PA-- Remove Highlighting --
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FXUS61 KCTP 180328
Area Forecast Discussion
National Weather Service State College PA
1028 PM EST Tue Jan 17 2017
A warm front will lift across the region this evening followed by
a cold frontal passage late tonight and early Wednesday. High
pressure will follow and bring mainly dry conditions with
temperatures several degrees above normal from the middle of the
week into the weekend.
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
The combination of cold dense air trapped in the valleys and
increasing moisture associated with the approaching occlusion/warm
front is causing areas of fog. The front appears to be so weak it
is sliding over the low level cold air, leading to diminishing
hopes that we will scour out any time soon. This suggests a
rather murky start to Wednesday with low clouds gradually lifting
and breaking up by late morning into the afternoon as a secondary
cold front brings a stronger push of cooler-drier air/
The new airmass will not be especially chilly, barely cold enough
to produce a flurry on the trough`s backside, but those will favor
the usual higher elevation terminals of the west.
Low temps early Wednesday will range from the mid 30s acrs the
northern mountains, to the lower 40s in the south.
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
Gradual improvement is expected as the Wednesday wears on...but
it will be a slow process as 5h low drops ESE to the Del Marva by
afternoon...helping a secondary front drop across the area to
signal improvement in the afternoon. Skies will be mostly cloudy
throughout with some brightening mid to late afternoon south
central and southeast. Highs will range from the upper 30s north
to around 50F southeast.
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
Ridge re-establishes itself over the eastern U.S. for late in the
week, as mild SW flow persists over the midwest. Guidance suggests
energy will dive south along the west coast eventually helping to
strengthen the building upper ridge over the east. We`ll be on the
eastern side of this, so subtle shortwaves sliding into the
Midwest will bring varying amounts of cloudiness to the west (less
in the east) with low end chances for light showers.
Another wave approaches/lifts into the OH valley late next weekend
into next Monday. Again, temps could be marginal at the start
of pcpn overnight Sunday for some ice or snow, but the bulk of
pcpn looks to be rain at this point. However, some guidance
suggesting enough presence of cold air to for wintry p-types
across northern PA.
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
Warm front lifting very slowly across the region is being caught
by the cold front as it pushes across Central PA this evening and
Thus, widespread MVFR to IFR conditions expected (with areas of
dense fog possible) through much of the overnight with
showery/drizzly conditions as flow not strong enough to scour
things out. Pockets of -fzra remain possible across the northern
airspace thru 15z but marginal surface temperatures should limit
icing impact. Even KJST which is currently VFR at 02z will
deteriorate behind the cold front in moist upslope flow.
Gradual improvement will begin toward sunrise as flow picks up
from the west. Should see improvement initially across the
southern mountains and spreading into the susquehanna valley by
mid morning. As always, improvement will be slowest across the
west, which may not see VFR reached until Thursday.
Wed...MVFR/IFR west. MVFR to VFR central-southeast. Rain showers
west ending Wed ngt.
Thu...No sig wx.
Fri...Sub-VFR possible with rain moving SW-NE.
Sat...No sig wx.
Sun...No sig wx.
Dense Fog Advisory until 6 AM EST Wednesday for PAZ004>006-
NEAR TERM...La Corte