770
FXUS61 KCTP 041013
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
613 AM EDT Fri Jul 4 2025

.SYNOPSIS...
* Incredible weather for Independence Day with plenty of sun,
  seasonable temperatures and comfortable humidity
* Warming trend into the first weekend of July with hot/humid
  conditions expected to peak Sunday and Monday
* Isolated t-storms possible downwind of Lake Erie and over the
  Allegheny/Laurel ridgetops Saturday afternoon and evening;
  daily chances for showers and t-storms next week

&&

.NEAR TERM /THROUGH TONIGHT/...
Nighttime IR channel difference imagery is detecting fog in the
valleys across the northern tier of CPA into the Coal Region
and Poconos/NEPA. Radiational cooling along with spotty rainfall
last evening and air/water spread >= 20 degrees are all
contributing for fog formation. A quick check of mesonet obs
indicates some of the usual cool spots in the northern mtns
should dip into the upper 40s prior to sunrise; the last time
BFD had a low temp in the 40s was back on June 11th. Fog will
dissipate quickly between 7-8AM in most locations.

An incredible Independence Day for CPA with abundant sunshine,
seasonable temperatures, 0% chance of rain and low/comfortable
humidity. Max temps between 75-85F are within +/- 3 degrees of
4th of July climo. Continued to lean on the low-end of the
guidance for dewpoints which drops minRH AOB 40% in most areas.

Good viewing conditions for fireworks tonight with mainly clear
to partly cloudy skies and overnight low temps in the 50-60F
range. That said, very light wind and low level nocturnal
stability should impact/limit smoke dispersion. Some valley fog
is also possible again in a few spots late tonight into early
Saturday morning.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Warming trend expected over the first weekend of July along with
an uptick in humidity/dewpoints. Max temps on Saturday are +3-8F
warmer vs. Friday, but dewpoints/humidity levels remain generally
tolerable/seasonable in the 60-65F range. That changes by
Sunday by adding another 2-4 degrees to max temps (mid 80s to
low 90s) with Td climbing above 65F in the central and eastern
valleys. In other words, hot and humid by the end of the holiday
weekend with min temps also making a series of higher-lows.

In terms of precip, there is an emerging signal in the HREF for
isolated to scattered diurnal showers/t-storms downwind of Lake
Erie and over the ridgetops along the Allegheny Plateau and
Laurels. We coordinated with BUF & CLE to add low POPs across
the NW mtns Saturday afternoon and evening which also lines up
well with SPC general/non-severe thunderstorm outlook area.
Sunday still looks rain-free for now as CPA will be in the
squeeze play subsidence zone between approaching cold front to
the west and potential tropical/subtropical depression near the
Carolina coast. Warmer temps aloft @700mb should also suppress
any terrain induced convection.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
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 /10Z FRIDAY THROUGH TUESDAY/...
The little bit of valley fog that has developed overnight should
quickly dissipate over the next couple hours as the surface
begins to heat up. A beautiful day is on deck for this 4th of
July. Skies are expected to remain clear and winds will be light
and variable. Dry conditions and VFR will prevail throughout the
day and into tonight.

There will again be the possibility for some early morning
valley fog across the airspace, but impacts to airfields is
expected to remain limited. Overall confidence in fog
development remains low.

Outlook...

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

Mon-Tue...Potential for showers and thunderstorms.

&&

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

&&

$$

SYNOPSIS...Steinbugl
NEAR TERM...Steinbugl
SHORT TERM...Steinbugl
LONG TERM...Colbert
AVIATION...Bowen