State College, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

579
FXUS61 KCTP 161807
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
207 PM EDT Thu Jul 16 2026

.WHAT HAS CHANGED...
* Code Purple air quality alert issued for northwest PA today
* Lowered temperatures and dewpoints into the weekend to account
  for smoke layer, clouds/t-storms, and systematic model bias

&&

.KEY MESSAGES...
1) Wildfire smoke from Ontario and northern Minnesota will
result in unhealthy air quality and reduced visibility today
and Friday

2) Monitoring potential for strong thunderstorms across the
southern tier of central PA late this afternoon/early evening

3) Strong to severe thunderstorms with heavy rainfall are
possible Saturday afternoon and evening

&&

.DISCUSSION...
KEY MESSAGE 1: Wildfire smoke from Ontario and northern
Minnesota will result in unhealthy air quality and reduced
visibility today and Friday

Widespread smoke continues to reduce visibility (generally 1-3
miles in FU and HZ) and drop AQIs from north to south this
afternoon. PA DEP will upgrade a portion of northwest PA to code
purple for very unhealthy air quality (AQIs 201-300). Code red
air quality alert continues for the rest of the Commonwealth
through the remainder of today. Code orange air quality is
forecast for Friday, but may be upgraded later today. These
alerts are based on predicted 24 hour averages. Individual hours
may see worse air quality.

Incremental adjustments to daytime temperatures: 1) lower
through Friday due to the extensive smoke layer 2) lower on
Saturday due to projected early arrival of clouds and rain
showers. Lower adjustments were made to dewpoints across the
board due to systematic NBM model bias.

Max heat index values may briefly touch 100 degrees in parts of
the Lower Susquehanna Valley early this afternoon before
dewpoints mix out a few degrees behind NW downslope flow.

KEY MESSAGE 2: Monitoring potential for strong thunderstorms
across the southern tier of central PA late this afternoon/early
evening

Mesoanalysis shows plenty of MLCAPE available in southern PA
with hot temps and rich low level moisture in place. Sfc front
is about to push southward through State College/KUNV with
dewpoints in the upper 50s to the NW. Forecast soundings show
30-40 kt of effective bulk shear and steep low-level lapse rates
present south of the front. This environment would generally
support organized cells/line segments. However, overall
thunderstorm coverage remains uncertain given that stronger
forcing for ascent should remain mostly north of the warm
sector. Additionally, it is uncertain to what extent that smoke
may continue to have a negative impact on an otherwise favorable
environment for severe thunderstorms.

KEY MESSAGE 3: Strong to severe thunderstorms with heavy
rainfall are possible Saturday afternoon and evening

A potent cold front trailing a deepening sfc low tracking up
the St. Lawrence River Valley is expected to trigger one or more
rounds thunderstorms Saturday afternoon and evening. Southwesterly
low-level flow ahead of the front will transport a very moist,
high PW airmass into CPA. Strong synoptic forcing, driven by an
amplifying trough over the Northeast and favorable upper jet
dynamics, will support the potential for heavy rain rates to
produce isolated runoff/flash flooding concerns. WPC may update
the D3 excessive rainfall outlook one category from level 1 MRGL
to level 2 SLGT with the late afternoon cycles.

SPC level 2/5 severe thunderstorm risk continues cover most of
central PA for day 3/Saturday. As thunderstorms initiate along
the front, outflows may eventually congeal into one or more
linear clusters posing a threat for damaging winds. Reduced
instability may be a limiting factor if clouds and showers
persist from early in the day.

A drying trend is expected Sunday with noticeably lower
humidity allowing for a pleasant day and relatively cool night.
Additional bouts of rain/t-storms are possible into the
workweek. Temperatures will trend near to below historical
averages through late week with some noticeable cooler nights
possible.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
The primary concern during the 18Z TAF period will be
visibility restrictions due to wildfire smoke from Canada and
northeastern Minnesota, with brief visibility improvements
(MVFR-VFR) possible along a cold front moving south across the
Commonwealth before visibility once again deteriorates. While a
stray shower or thundershower cannot be ruled out this
afternoon/evening across our southern tier, mainly dry
conditions remain favored, especially given the smoke coverage.

Tonight may bring the most widespread restrictions as winds
lighten behind the front with high pressure moving in, with the
HRRR/RRFS models showing IFR to LIFR visibilities across much of
Central PA. Improvements from overnight IFR-LIFR on Friday is
favored across the northeastern edge of the smoke plume
(currently forecast to be KBFD/KIPT/KLNS), where the wind`s
northerly component may linger enough to bring smoke south of
those sites, with improvements looking less likely over
southwestern Pennsylvania (KJST/KAOO) where the winds may lighten
as the core of the smoke plume moves overhead.


Outlook...

Sat-Sun...Chance of showers and t-storms, mainly during
the afternoon hours on Saturday into early Sunday aft.

Mon...Mainly VFR.

Tue...Restrictions possible in showers/t-storms.

&&

.EQUIPMENT...
GOES-19/GOES-EAST recovery update: operations resumed at 1630Z.
Engineers are currently working to restore the Advanced
Baseline Imager (ABI) with imaging expected to resume by 19-20Z.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Air Quality Alert until midnight EDT tonight for PAZ004>006-
010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066.

&&

$$

WHAT HAS CHANGED...Steinbugl
KEY MESSAGES...Steinbugl
DISCUSSION...Steinbugl
AVIATION...Teare
EQUIPMENT...Steinbugl