Allentown, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

895
FXUS61 KPHI 252339
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
739 PM EDT Sat Jul 25 2026

.WHAT HAS CHANGED...
Aviation section updated for the 00z TAFs.

&&

.KEY MESSAGES...
1) Showers and thunderstorms return and increase along with
increasingly more humid for the first half of next week. There is
also the potential for areas of heavy rain and some strong to severe
thunderstorms Tuesday.

&&

.DISCUSSION...
KEY MESSAGE 1...Showers and thunderstorms return and increase along with
increasingly more humid for the first half of next week. There is
also the potential for areas of heavy rain and some strong to severe
thunderstorms Tuesday.

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 vigorous shortwave
riding over the ridge and sliding southeastward across the Great
Lakes Monday and then across the Northeast during Tuesday. This
results in some model solutions continuing to close off the trough
across the Northeast Tuesday into Wednesday. Some other guidance is
slower and weaker and thus does not close it off or briefly closes
it off a day or two later. The upper-level system will drive surface
low pressure and a cold front our way Tuesday into Wednesday. It
will become much more humid during the first half of next week, with
dew points looking to surge on Tuesday.

This will all result in an increase in convective chances Monday and
especially Tuesday into 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
continue 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 should result in widespread showers and
some thunderstorms which maximizes on Tuesday. Depending on the
evolution of this system, some areas of heavy rainfall (precipitable
water values increase to 1.5-2.00 inches) and some severe
thunderstorms are possible. The intensity and coverage of
thunderstorms though may partially depend on the prior days
convective development and then its evolution downstream.

&&

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

Tonight...VFR. East-southeast winds around 5 knots, becoming
light and variable to calm. High confidence.

Sunday...VFR. East-northeast winds around 5 knots in the morning
become east-southeast around 5-10 knots in the afternoon. High
confidence in VFR conditions.

Outlook...

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 showers and
thunderstorms. Southerly wind gusts up to 20 knots possible.

Wednesday and Thursday...Some sub-VFR conditions possible with
a few showers and thunderstorms.

&&

.MARINE...
The conditions are expected to remain below Small Craft Advisory
criteria through Sunday. Winds mainly out of the east around 10
kts or less with seas of 2-3 feet.

Outlook...

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

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

Wednesday and Thursday...The conditions are anticipated to be
below Small Craft Advisory criteria.

Rip Currents...

For Sunday, east-northeast winds generally around 10 mph. Breaking
waves of 2-3 feet for the Jersey Shore and 1-2 feet for Delaware
beaches. Dominant northeasterly swell around 3 feet at 6-7 seconds
in length, with an additional southeasterly swell of 1-2 feet at
around 8 seconds. Have maintained the MODERATE risk for the development
of dangerous rip currents at all area beaches.

For Monday, south winds around 5-10 mph. Breaking waves of 1-2
feet along most of the coast, though they could approach 3 feet
for southern parts of the Jersey Shore. There will be multiple
swell groups, but all of them look to be fairly light and short
in period. Given the more shore-parallel flow and light swell,
there is a LOW risk for the development of dangerous rip
currents at all area 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...AKL/Gorse/RCM
AVIATION...AKL/OHara/RCM
MARINE...AKL/Cooper/RCM