253
FXUS61 KCTP 060245
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1045 PM EDT Fri Jul 5 2024

.SYNOPSIS...
* Persistent heat and humidity stick around through next week
* Aside from a few isolated showers and storms on Saturday, a
  dry weekend is expected
* Trending wetter toward the middle of next week with daily
  chances for showers and thunderstorms.

&&

.NEAR TERM /UNTIL 8 AM SATURDAY MORNING/...
Still remarkably muggy out there this evening with temperatures
holding in the middle 80s and dewpoints in the middle 70s across
southeast PA. The persistence of heat/humidity with no real
relief overnight has prompted the extension of the Heat Advisory
until 8PM Saturday for the Lower Susquehanna Valley.

Mid level ridge axis overhead combined with a strong cap
(9.5-10.5C at 700 mb) and earlier widespread and relatively
thick, layered cloud cover has minimized development of much
shower/storm activity thus far. Conditions have become more
favorable for shower activity this evening across the west and
will spread east overnight across the Central Zones and much of
the Susq Valley as a subtle shortwave/few deg C of cooling aloft
moves NE up the Ohio Valley. Showers could still linger until
daybreak in the far NE. A few rumbles of thunder are possible,
but recent trends indicate the threat for severe weather is
very low overnight.

Sfc dewpoints in the upper 60s to mid 70s and the increasing
cloud cover advecting in with the decaying storms from the SW
will lead to a very warm and muggy night with min temps
similarly in the upper 60s to mid 70s. Localized, briefly cooler
temps in the mid 60s may occur where rain falls. Saturday
morning will epitomize the phrase "air you can wear".

&&

.SHORT TERM /8 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
Focus for t-storms will shift to the eastern third of the
Commonwealth (Mainly Saturday PM) along and ahead of a weak
cold front. A second area of SHRA/Low-topped TSRA are possible
along the boundary of the Lake Erie Breeze that should reach NW
Warren County and perhaps NW McKean Cty.

HREF and its members suggests limited storm coverage likely
owing to neutral height falls and weak llvl convergence. Cold
front passage has trended a bit faster, so majority of storms
should remain east of the area tomorrow and keep most locations
dry. Ahead of the front, surface temperatures in the middle 90s
will combine with dewpoints still in the upper 60s to middle
70s to produce heat index values near or above 100F Saturday
afternoon where a Heat Advisory remains in effect. With little
to no chance of rain/storms, only limiting factor for heat index
will be the frontal passage. Behind the cold front, dewpoints will
trend a bit lower (lower 60s) and cap heat index in the 80s
(north & west) and 90s (outside the Lower Susquehanna Valley).

High pressure builds in Saturday night and provides a slightly
less humid and dry (rain-free) end to the first weekend of July.
Lows by Sunday morning will dip into the upper 50s in northwest
but stay in the low 70s in the southeast. Clearing skies and
ideal radiational cooling should support valley fog in the
northwest on Sunday morning. Plenty of sunshine expected Sunday
with clear skies Sunday night and temperatures similar to
Saturday/Saturday night with slightly lower humidity.
It may be worthwhile to find a pool or body of water near which
to participate in outdoor activities this weekend.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Diurnally driven showers and thunderstorms appear possible on
Monday with easterly/southeasterly flow bringing an increase of
moisture to central Pennsylvania. Surging PWATs into Tuesday
will promote higher chances of precipitation later in the
evening and into Wednesday morning as a surface cold front
approaches the region. Precipitation is expected to continue
through late Wednesday when the cold front shifts east of the
area, but have retained PoPs through the end of the Wednesday
timeframe based on some remaining uncertainty with regards to
timing.

Some divergence in model solutions on Thursday and into the end
of the week with the North American suite of models outlining
surface high pressure taking hold across the region while the
European suite of models outline a continuation of showers and
storms throughout the period, so have capped chances to SChc
outside of peak daytime heating hours where slightly higher
probabilities emerge.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Scattered showers, and possibly some thunder, will approach
from the Ohio Valley later this evening and should push
northeastward across the area through the overnight.

Ensemble guidance suggests that we will see a period of MVFR
cigs later tonight into Saturday morning over the western (BFD,
JST) highlands and the central mountains (AOO, UNV, and possibly
IPT). The western highlands may see cigs dip to IFR for a few
hours centered around daybreak (~60% chc).

Improvement is expected areawide on Saturday, with all
airfields returning to VFR conds by afternoon.

Outlook...

Sun...AM fog possible; otherwise, no sig wx expected with
slightly lower humidity.

Mon...Predominantly VFR w/ no sig wx expected.

Tue-Wed...Scattered showers/storms and restrictions possible.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM EDT Saturday for PAZ036-056-057-059-
063>066.

&&

$$

SYNOPSIS...Banghoff
NEAR TERM...Lambert/Banghoff
SHORT TERM...Lambert/Banghoff
LONG TERM...NPB
AVIATION...Evanego