Area Forecast Discussion
Issued by NWS State College, PA

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800
FXUS61 KCTP 090215
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1015 PM EDT Sat Aug 8 2026

.WHAT HAS CHANGED...
* Expect current near-severe storms to continue to weaken, but
  one or two may still end up producing wind damage.
* Expanded mentions of fog to much of the area overnight.

&&

.KEY MESSAGES...
1) Near-severe scattered thunderstorms over the NW will be on a
gradual down/weaking trend for the rest of the night.

2) Mainly dry for Sunday, though daily chances for showers and
thunderstorms return to the forecast for next week.

&&

.DISCUSSION...
KEY MESSAGE 1: Near-severe scattered thunderstorms over the NW
will be on a gradual down/weaking trend for the rest of the
night.

Storms continue to roll in from western PA at 10 PM EDT. Some
were more-potent over the last 3 hours, but have been on the
down-trend as we have lost the heating of the day. Synoptic
forcing is generating additional storms at this time, and a
flash flood threat has begun for the places that recived heavier
rain earlier iun the evening. Rain gauge in Grand Valley has
over 4" this evening. If that is accurate, the radar estimates
are underdoing what has fallen. Too sparse of coverage to go
with a flood watch at this point. Will cover what needs to be
covered with timely warnings.


KEY MESSAGE 2: Mainly dry for Sunday, though daily chances for
showers and thunderstorms return to the forecast for next week.

Upper level flow becomes more zonal for Sunday which should
result in a mainly dry day, outside of an isolated shower or
storm that develops on the higher terrain of western PA. The
break from the rain will be short-lived, however, as multiple
shortwaves moving through will bring daily chances for showers
and storms as we head into the coming week.

Machine learning ensembles suggest that there will be some
severe weather potential for at least a couple of days next week
and SPC has much of the region outlooked in a marginal risk for
Monday. There will also be some potential for flash flooding as
well, and WPC has placed all of central PA in a marginal risk
for both Monday and Tuesday. There is still some uncertainty
regarding the severe and flash flood risks, but the details will
be worked out over the coming days.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
Scattered showers and thunderstorms across NW PA will gradually
track eastward over the next couple of hours before decreasing
in intensity. Current shower/storm activity appears to be
tracking towards BFD; however, lower confidence on whether
lightning will make it that far east base on similar storms in
the area. Thus, have kept the PROB30 group and narrowed down the
timeframe for an hour where TSRA/SHRA will be most likely.
Radar does outlines some SHRA/TSRA along and just south of the
I-80 corridor; however, guidance continues to struggle these
making it much further east and impacting UNV/IPT this evening.

Potential still exists for low cloud and patchy fog development
overnight with highest potential at BFD where SHRA/TSRA is most
likely over the next couple of hours. Guidance does indicate
some potential at UNV; however, 25th percentile members of the
HREF ensemble outlines VFR conditions for the airfield. Thus,
have kept UNV and IPT VFR throughout the TAF package,
especially given relatively dry low-levels at 00Z with a light
breeze possible overnight. An additional area of fog/low cloud
development is likely across south-central Pennsylvania but
impacts at AOO/MDT/LNS appear unlikely at this time. A slight
uptick in low-level moisture at JST does warrant some mentions
of MVFR-to-IFR ceilings and have highlighted this potential
based on a HREF/GLAMP model guidance blend.

After sunrise, fog/low clouds likely mix out quickly and lead to
widespread VFR conditions through 00Z Monday. Some isolated
showers will be possible; however, best chances for any
precipitation mentions likely come after 00Z Monday, thus have
decided to keep any SHRA mentions out of the 00Z TAF package.

Outlook...

Sun...Mostly dry, some isolated showers across far W PA.

Mon-Thu...Scattered showers/storms. Restrictions possible.

&&

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

&&

$$

WHAT HAS CHANGED...Dangelo
KEY MESSAGES...Dangelo/Bauco
DISCUSSION...Bauco
AVIATION...Beaty