865
FXUS61 KCTP 051121
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
721 AM EDT Fri Jul 5 2024

.SYNOPSIS...
*Very warm and humid summertime pattern with above average
 temperatures continues into next week
*Showers and thunderstorms are possible in spots today and
 Saturday followed by a rain-free end to the first weekend of
 July

&&

.NEAR TERM /THROUGH TONIGHT/...
7AM/11Z: Sfc obs and MRMS radar show a weak wave of low
pressure moving east northeastward across north central PA
early this morning. Expect leading edge of main rain area to
to pivot through the northeastern quadrant of the CWA through
12-13Z.

The latest hires guidance continues to favor a suppressed
convective scenario for today - leaning bearish for t-storms and
potential severe risk - with very limited development through
the afternoon and into the evening hours. Early day cloud cover
and shower activity (leading to reduced instability) appear to
be the primary contributors. CAM signal remains consistent in
ramping POPs higher across the NW zones closer to 00Z.

Previous Discussion Issued: 423 AM EDT Fri Jul 5 2024

Hires models are in good agreement tracking a cluster of
rain showers/embedded thunder with brief heavy rain across the
northern half of the forecast area through 18Z. We will adjust
precip probs upward based on this bullish signal. Lingering
cloud cover and subsidence behind the early day rain appears to
result in a lull/min in precip this afternoon. CAMs suggest
some additional convection could develop later this
evening/closer to 00Z over the western into the central zones,
but overall confidence is low. CAPE and shear profiles are
supportive of isolated severe t-storm potential with a large
MRGL risk SWO covering most of the CWA. However, timing remains
a wildcard and could end up being to late in the day/after dark.

Another hot and humid summer day across CPA with highs in the
85-95F range. With the humidity (dewpoints 70-75F), it will feel
like 100-102 degrees across portions of south central PA
particularly in the lower Susquehanna Valley. Max HX values
ticked higher above the century mark and we coordinated with
WFO PHI on the issuance of heat advisory from noon to 8PM. A
couple of showers/t-storm will could linger overnight which
will be very warm and muggy with low temps 65-75F.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Focus for t-storms will shift to the eastern periphery of the
CWA on Saturday PM along and ahead of a weak cold front. Despite
a very moist/unstable environment, most model guidance suggests
limited storm coverage likely owing to neutral height falls and
weak llvl convergence. That said, still can`t rule out a couple
of strong t-storms over eastern PA.

High pressure builds in Saturday night and provides a slightly
less humid and dry (rain-free) end to the first weekend of July.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
All medium range guidance supports fair weather and above
average temperatures into early next week with upper level
ridging indicated over the northeast. At the surface, high
pressure is progged to build over Pennsylvania Sunday, then pass
off of the east coast early next week. The return southerly
flow should result in an uptick in heat/humidity early next
week.

Diurnally driven showers and thunderstorms appear possible on
Monday based on recent GEFS plumes but guidance continues to
suggest a better chance of precipitation on Tuesday with the
arrival of a cold front during the afternoon hours. There is
still a fair amount of uncertainty with regards to the cold
front clearing eastern Pennsylvania later on Wednesday, so have
retained PoPs through this timeframe. Towards the end of the
period, deterministic guidance begins to outline high pressure
influence into the region; however, given so much uncertainty
earlier in the forecast period have opted not to deviate from
NBM PoPs at this time.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
An area of showers are continuing to linger across NE PA this
morning at sunrise. Many sites across the region are
experiencing category reductions due to fog development, low
stratus, and the aforementioned showers. Most sites are
borderline MVFR to IFR with low cloud decks drifting towards
the east.

Conditions will likely improve to VFR fairly quickly after
sunrise across most of the area, though it could take until late
morning for BFD and IPT to see the low ceilings improve.
Scattered showers and thunderstorms will be possible again later
this afternoon, though coverage looks to be more limited than
what occurred Thursday. VFR will likely persist through Saturday
morning with the only restrictions coming in the form of a
scattered shower or thunderstorm.

Outlook...

Fri...Sct TSRA w/ possible impacts; Mainly PM w/ highest
coverage across the west.

Sat...Sct to Nmrs TSRA areawide, highest chances SE in PM.

Sun...AM fog possible; otherwise, no sig wx.

Mon...SHRA possible SE late PM; otherwise, no sig wx.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from noon today to 8 PM EDT this evening for
PAZ026>028-035-036-056-057-059-063>066.

&&

$$

SYNOPSIS...Steinbugl
NEAR TERM...Steinbugl
SHORT TERM...Steinbugl
LONG TERM...Fitzgerald/Martin/NPB
AVIATION...Bauco/Bowen