Allentown, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

529
FXUS61 KPHI 242307
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
707 PM EDT Fri Jul 24 2026

.WHAT HAS CHANGED...
Aviation section updated for the 00Z TAF issuance.

&&

.KEY MESSAGES...
1) Shower and thunderstorm chances increase for the first half of
next week with the potential for areas of heavy rain and some strong
thunderstorms.

&&

.DISCUSSION...
KEY MESSAGE 1...Shower and thunderstorm chances increase for the
first half of next week with the potential for areas of heavy rain
and some strong thunderstorms.

As a strong upper-level ridge expands into the Plains early next
week, northwesterly flow aloft will occur across much of the East.
This ridge gets pushed back some as a potentially strong upper-level
trough in eastern Canada sends spokes of energy southeastward across
the Great Lakes and Northeast. This will initially allow for the
upper-level trough to become more carved out across the Northeast by
later this weekend. Some guidance maintains a rather vigorous
shortwave sliding southeastward across the Great Lakes Monday and
then across the Northeast during Tuesday. This results in some model
solutions closing off the trough across the Northeast Tuesday into
Wednesday. Some other guidance is slower and thus sharpens or closes
off the trough a day or two later. The upper-level system will drive
surface low pressure and a cold front our way Tuesday into
Wednesday.

What all this boils down to is that it looks like we start to turn
convectively active by Monday, with the most active day likely to be
Tuesday, and then convection starting to decrease in activity
Wednesday. While there remains some differences among the model
guidance on the timing and strength of the features diving
southeastward early next week, the setup would tend to favor
upstream convective development given northwesterly flow aloft. This
would be enhanced if the trough aloft closes off. Deeper moisture
(dew points into the low 70s) advecting northward ahead of this
feature with eventual cooling aloft and stronger forcing for ascent
may result in widespread showers and some thunderstorms. Depending
on the evolution of this system, some areas of heavy rainfall and
strong thunderstorms are possible. The intensity and coverage of
thunderstorms though may ultimately depend on the prior days
convective development and then its evolution downstream.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Tonight...VFR with SCT/BKN high clouds. Southeast winds around
5-10 kt early, will diminish and become light and variable by
around 03Z with calm periods likely. High confidence.

Saturday...VFR with mainly clear skies. East-northeast winds
around 5-10 kt, shifting to east-southeast in the afternoon. A
few gusts 15-20 kt possible, especially at ACY. High confidence.

Outlook...

Sunday...VFR. No significant weather.

Monday...Some showers and thunderstorms in the afternoon and at
night with some times of sub-VFR conditions.

Tuesday...Times of sub-VFR conditions with some showers and
thunderstorms.

&&

.MARINE...
No marine headlines are in effect through Saturday. East-
northeast winds around 10-15 kt are expected through tonight,
with winds ranging between 10-20 kt on Saturday. Seas around 2-3
feet. Fair weather.

Outlook...

Sunday through Monday...The conditions are anticipated to be
below Small Craft Advisory criteria.

Tuesday...Small Craft Advisory conditions possible as southerly flow
increases.

Rip Currents...

For Saturday, east-northeast winds 10-20 mph with breaking
waves 2 to 3 feet with multiple swell groups and a period of
around 7 seconds. For these reasons, there is a MODERATE risk
for the development of dangerous rip currents at all beaches.

For Sunday, northeast winds of 10-20 mph become more easterly
through the afternoon at 5-10 mph. Breaking waves of 2 to 3
feet remain with multiple swell groups and a period of 7-8
seconds. For these reasons, there is a MODERATE risk for the
development of dangerous rip currents at all beaches.

For specific beach forecasts, visit weather.gov/beach/phi

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.

&&

$$

DISCUSSION...Gorse/RCM
AVIATION...Cooper/DeSilva/Gorse
MARINE...DeSilva/Gorse/Guzzo