-- Discussion containing changed information from previous version are highlighted. --
819
FXUS61 KCTP 032018
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
418 PM EDT Thu Jul 3 2025

.SYNOPSIS...
* Scattered storms late this afternoon and very early evening as
  a cold front moves through. Some may be accompanied by strong
  gusty winds and hail.
* Drier/less humid/more comfortable conditions are likely for
  Independence Day.
* Trending warmer and more humid but rain-free this weekend
* Hot and unsettled weather returns next week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Surface cold front extended from the Finger Lakes of NY to NW PA
at 19Z. Isolated to SCT TSRA developed over the past few hours
and are moving rather quickly to the ESE at 35 to 40 mph.

Plenty of morning sunshine has allowed sfc based CAPE to grow
to around 2000 J/KG across much of the CWA, just ahead of the
cold front.

The left exit region of the Glakes Jet max will brush across
the NE third to half of the CWA late this afternoon and early
this evening, interacting with the approaching sfc cold
front/Lake Erie Breeze and accentuating UVVEL for some fast,
southeast- moving discrete TSRA (Supercells and mini-bows)
capable of producing localized 60-70 mph downburst gusts and a
few instances of quarter sized hail. Strong low level storm
relative inflow and slightly curved 0-3 KM hodographs along
relatively cool mid level temps and a Wet Bulb Zero level of
about 9 KFT AGl supports the threat for large hail.

Severe Thunderstorm Watch #484 is in effect for the NE quarter
of the CWA until 02Z, but since we`re at the western edge of
this watch area, the effective time for it in our CWA should be
through about 22-23Z.

Some lingering SHRA (and maybe a brief, low-topped TSRA will
last until just after sunset in the SE, but it`s only worth a
15-20 PoP for isolated coverage. After the front passes, which
will be early this evening in the S, the air will dry out
substantially with sfc dewpoints into the 50s by sunrise
Friday (likely to between 45 and 50F over the Northern Mtns with
PWAT values across the north dipping to under 0.50 of an inch).

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
Friday looks like a stellar Independence Day.

No risk of any precip, and humidity dipping to bone dry levels
in the afternoon. Will continue to deviate to the low side from
the NBM dewpoints for Fri and Sat afternoons, with Friday being
the largest diff in Td.

Light N wind and plenty of sunshine Fri. Very dry air just
above the sfc in the AM and mixing to ~5kft in the aftn could
drop dewpoints into the 40s across the Allegheny Plateau and
M50s in the SE. That may not be enough of a move, but will start
with that.

High temps Friday in the U70s to M80s are very seasonable, and
we`ll probably see temps a few deg F higher Sat aftn.

High pressure building SE over the Commonwealth will provide
dry conditions for both days.

Patchy 1/2SM fog will develop in the valleys of Central and
Northern PA since temps dip close to 50F in the nrn mtns Fri
AM with air/water delta Ts exceeding 20F in some places.
However, the dry airmass will work against more widespread fog
formation.

Dewpoints are going to be low enough on Sat AM that there won`t
be much, if any, fog. Then, the wind turns Swrly, and humidity
levels start to creep upward during the long holiday weekend,
but no rain.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Most of the day Sunday looks hot and mostly sunny with highs in
the upper 80s. PoPs increase into Monday and Tuesday as a
trough arrives and taps into some tropical moisture off the
East Coast. Very warm weather will continue on Monday with highs
in the mid to upper 80s. Temps will fall a few degrees into
Tue. PoPs drop into the 20-40 pct range on Wed as heights
briefly rise over the area, before the PoPs rise again Thursday
with the approach of another shortwave trough.

&&

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
Late afternoon update.

Adjusted TAS for current showers and storms and trends with
winds.

Held onto TEMPO group at LNS, nothing much down that way,
but still some chc of a storm working southward into that
area next few hours.

Earlier discussion below.

The main focus through the 12Z Friday will be a shortwave that
will traverse the region and bring mainly isolated showers and
thunderstorms to portions of the area into early this evening
(across mainly the eastern half of the CWA) as a surface cold
front (associated with this upper level shortwave) pushes SE
across the SE half of the state.

This cold front will be largely moisture starved, However,
given the instability in the eastern portion of PA it is
possible isolated to scattered storms may cause some flight
impacts.

These thunderstorms will have the best chance of impacting IPT,
MDT, and LNS, while areas farther to the west likely remain
dry.

Generally VFR tonight and for the entire long holiday weekend,
but a brief few hour period of fog is possible at KBFD and at
other airfields in the valleys of central and eastern PA.

Outlook...

Sat-Sun...AM fog possible; otherwise VFR.

Mon-Tue...Thunderstorms developing in the afternoon.
-- End Changed Discussion --

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Lambert/Dangelo
NEAR TERM...Lambert/Dangelo
SHORT TERM...Lambert/Dangelo
LONG TERM...Colbert
AVIATION...Lambert/Martin