Area Forecast Discussion
Issued by NWS State College, PA-- Remove Highlighting --
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FXUS61 KCTP 291047
Area Forecast Discussion
National Weather Service State College PA
647 AM EDT WED JUN 29 2016
High pressure will bring a period of mainly dry weather with
comfortable humidity for Wednesday and Thursday. A cold-frontal
system will approach for the end of the week. The holiday weekend
is looking mainly dry with temperatures close to or just slightly
below normal for early July.
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
The few srha in the N have pretty much dissipated. Will keep a
mention in there in case the heating and cyclonic flow decide to
team up later this morning. Clouds over the NW will start to break
up this morning as the trough axis slides to the east.
Upper low and good dynamics over western NY are helping to
generate lake effect showers which are sneaking into the far NW.
The deepest part of the trough should slide eastward through the
rest of the night and during the first half of the day. Will just
nudge POPs into the 15-20percent range to mention the possibility
that it may sprinkle right along the NY border. These may be gone
by mid-afternoon, but daytime heating may re-generate convection
or at least keep it going. Again, just a slight chc and mainly in
the morning. Some fog is forming in the eastern valleys where some
heavy rain fell yesterday. Expect the fog to linger for a few
hours after sunrise.
Off to the south...a cluster of showers is dissipating as it
reaches the Lower Susq. All this should be done in the next hour
or so. Drier air is on the way to the eastern zones. They have
been languishing in the U60s to L70s for dewpoints for a while
and a drop into the 50s will make it feel so much more
comfortable/refreshing. Will keep the forecast dry for the
balance of the area today as the dry airmass will make it
difficult to make any diurnal cu grow to any more than just a few
kft. 8H temps dip 3-5C over much of the area but hang close to
current numbers around +10C in the NW. This should bring the maxes
in 2-5F below normals.
.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM THURSDAY/...
A really comfortable night is in store tonight. It is not out of
the question that the valleys in the northern mountains could get
to 40F. Most of the area will be in the 50s for mins. A few
clouds over the southern third of the area could keep temps from
getting below 60F there.
Thursday is an interesting forecast with the potential for a very
minor short wave trough to move across during the daytime. The air
is pretty dry and very few triggers will exist - other than the
hill tops. Most if not all of the area should stay dry with
little moisture. There is just a slight chance of a shower popping
up in the aftn across the srn hill tops where dewpoints will be
closer to 60F. Maxes will warm 3-6F over Wed as a light south wind
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
The mean upper trough over the Northeastern CONUS loses amplitude
through the period, as a closed 500mb low dropping southward near
James Bay shifts eastward and a subtropical ridge off the Southeast
coast retrogrades slowly westward into the Gulf of Mexico. The
large scale pattern will have a decidedly summertime look to it
as we turn the calendar page to the month of July, with the main
belt of polar westerlies located along the U.S./Canadian border
and expansive upper ridge covering the southern 1/2 of the Lower
While much of central PA could use some rain, odds are that most
of the period will be a dry one. A frontal system moving through
the area on Friday will likely provide the only opportunity for
rain (scattered showers/T-storms) until the second half of next
week /beyond July 6th/. The upside to this will be a seasonably
warm and dry period expected to last through Independence Day
with seasonal temperatures and tolerable humidity.
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
Most of the fog is gone. Very clean airmass in place now.
Some lower clouds now at JST.
09Z TAFS sent.
Earlier Decussion below.
Most of the showers and thunderstorms have moved eastward and/or
dissipated with the only remaining cluster east of AOO. The
eastern areas received copious amounts of rainfall on Tuesday.
Considering this, and that there remains a weak boundary over the
region with calm winds, there remains a higher probability for
reducing cigs early today...mainly across eastern areas. Did trim
back the fog some.
So far it looks like IPT will be foggy place overnight.
With the cold air aloft...and strong June sun...expect any low
cigs and fog to quickly mix out this morning.
Next chc for showers and storms will be Thursday Night across
the east. Maybe across the entire area on Friday...if both
Thu...No sig wx expected.
Thu Night-Fri...Isold tsra impacts possible.
Sat and Sun...No sig wx expected.