472
FXUS61 KPHI 031030
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
630 AM EDT Thu Sep 3 2026

.WHAT HAS CHANGED...
Updated aviation discussion for 12z TAFs.

&&

.KEY MESSAGES...
1. Multiple rounds of heavy thunderstorms will affect the area
through today into tonight bringing the threat of both severe
weather and flash flooding. Additional thunderstorms are
possible on Friday.

2. Hot and humid conditions are forecast across the region on
Thursday.

3. The Labor Day Weekend will feature mostly dry weather with at or
below normal temperatures and lower humidity.

&&

.DISCUSSION...
KEY MESSAGE 1...Multiple rounds of heavy thunderstorms will affect
the area through today into tonight bringing the threat of both
severe weather and flash flooding. Additional thunderstorms are
possible on Friday.

There are still some showers and storms ongoing at this hour but
these have diminished in intensity compared to earlier this
morning. By later in the morning through a good portion of the
afternoon there looks to be a lull in storms as some sunshine
develops with it getting quite warm and humid as the area breaks
into the warm sector with a WSE flow. This will lead to further
destabilization to occur. In fact ML CAPES looks to max out in
the 2000-3000 j/kg range. This will set the stage for additional
storms to occur along a cold front working south mainly as we
get into Thursday evening. There`s some uncertainty on the
timing and coverage of these storms and at this point the Storm
Prediction Center has most of the region in a MARGINAL risk of
severe thunderstorms meaning isolated severe storms are
possible. Only portions of our eastern MD shore counties are
grazed by the SLIGHT risk area that`s focused mainly to our
south and west. Similar to this morning, PWATs will be quite
high so flash flooding will be a threat as well.

Friday`s SPC outlook only has a small portion of the Maryland
Eastern Shore and southern Delaware in a Marginal risk for severe
weather. Th rest of the area includes general thunderstorms (no
severe risk), though there is still some uncertainty with this. Our
latest forecast has about a 40-70% chance of showers and
thunderstorms from about I-78 on southwards, including the entire
Philadelphia metro area.

KEY MESSAGE 2...Following the brief cool down that occurred
Wednesday, hot and humid conditions are once again expected across
the region on Thursday as the frontal boundary lifts north again.
With the front to the north, high temperatures are forecast to climb
into the upper 80s to mid 90s for many areas (low to mid 80s far
north). These temperatures combined with dewpoints in the low to mid
70s will again result in heat indices well into the 90s to low 100s
south of I-78, perhaps even as high as 105 degrees for Delmarva.

A Heat Advisory remains in effect for portions of southeastern PA,
NJ, and Delmarva. North of the current advisory area, maximum heat
indices are forecast to generally top out in the low to mid 90s.

KEY MESSAGE 3...The Labor Day Weekend will feature mostly dry
weather with at or below normal temperatures and lower humidity.

By Saturday, current model consensus indicates the frontal boundary
will be pushing well south of our region, with Canadian high
pressure building across the Northeast and Mid-Atlantic. This will
largely end any shower and thunderstorm potential. Thus, Labor Day
Weekend is still shaping up to feature nice weather, with
temperatures trending at or slightly below normal and lower
humidity.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Thursday...Mainly IFR cigs lifting to MVFR by around late
morning. Showers continue into this morning and still can`t rule
out some thunder though coverage and intensity of storms has
been on the wane the past couple hours. There should then be a
break of a few hours this afternoon before yet another round of
storms could affect the TAF sites very late in the afternoon
into the evening. SW winds 5 to 10 kt. Moderate confidence.

Thursday night...SHRA/TSRA may continue through the evening
before tapering off overnight. MVFR/IFR restrictions possible in
any storms. Light west winds. Moderate confidence.

Outlook...

Friday...Sub-VFR conditions are possible in showers and
thunderstorms (40-60% chance), mainly during the afternoon to
evening hours.

Saturday through Monday...Primarily VFR conditions expected.

&&

.MARINE...
Winds and seas are expected to stay below Small Craft Advisory
conditions. However, gusty and erratic winds are possible in the
vicinity of any storms, particularly early this morning and
again Thursday afternoon/evening.

Outlook...

Thursday night through Monday...Sub-SCA conditions are expected
through the period. There is a chance (20 to 50%) for
thunderstorms to linger Thursday night. For Friday, the chance
of thunderstorms is around 40 to 60%, mainly in the afternoon
and early evening hours.

Rip Currents...

For Thursday, winds will mainly be out of the south/southwest
around 10 MPH or less. Breaking waves will generally be 2 feet
or less with a dominant wave period of 9 seconds. Given light
winds, and not much in terms of wave heights, elected for a LOW
risk for rip currents at all beaches.

Similar conditions expected Friday though winds turn more
offshore, lowering the rip current risk even further. Will
continue the LOW risk through the end of the week for the Jersey
Shore and Delaware Beaches.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for PAZ060-070-071-101>104-106.
NJ...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for NJZ013>015-017>020-027.
DE...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for DEZ001>003.
MD...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for MDZ012-015-019-020.
MARINE...None.

&&

$$

DISCUSSION...Fitzsimmons
AVIATION...Fitzsimmons
MARINE...Fitzsimmons