670
FXUS61 KPHI 230609
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
209 AM EDT Thu Jul 23 2026

.WHAT HAS CHANGED...
Updated the aviation section for the 06z TAFs.

Updated all of the other sections.

&&

.KEY MESSAGES...
1) A much drier air mass will be in place through the end of the
week and to start the weekend.

2) Shower and thunderstorm chances increase early next week with the
potential for areas of heavy rain and strong thunderstorms.

&&

.DISCUSSION...
KEY MESSAGE 1...A much drier air mass will be in place through the
end of the week and to start the weekend.

Drier air continues to filter in from northwest to southeast early
this morning in the wake of a cold front. An impulse driving some
showers will exit southeastern New Jersey and southern Delaware
early this morning. The intensity of this activity has weakened
given drier air undercutting it from the northwest.

An upper-level trough will then gradually weaken across the
Northeast and northern Mid-Atlantic later today, tonight and Friday.
Surface high pressure builds across the Northeast and down into the
Mid-Atlantic through the end of the week before shifting offshore of
New England on Saturday. A northerly flow will keep a much drier air
mass across our area along with cooler temperatures. The lighter low-
level flow due to high pressure in place will result in some
enhancement to the sea/bay breezes later today and again on Friday.


KEY MESSAGE 2...Shower and thunderstorm chances increase early next
week with the potential for areas of heavy rain and 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 looks to get pushed back some as a potentially strong
upper-level trough in eastern Canada sends spokes of energy
southeastward across the Great Lakes and Northeast. Some guidance
has stronger shortwave energy which results in the trough closing
off across the Northeast with time during the first half of next
week. This will also drive surface low pressure and a cold front our
way around the Tuesday time frame. Some convection from upstream may
try and get into parts of our area later Sunday, however this is
less certain.

It looks like we may turn convectively active early next week,
especially Tuesday into Wednesday. While there are 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
advecting northward ahead of this feature with eventually colder air
aloft arriving may result in widespread showers and some
thunderstorms. While the specifics are uncertain at this time range,
some areas of heavy rainfall and strong thunderstorms are possible
given the overall synoptic setup that is forecast.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...VFR, with clouds gradually clearing from west to east
through the morning. There are a few showers near KMIV and KACY
early this morning, however these should be light with no
restrictions. North-northwest winds around 10 knots, becoming north-
northeast during the day. The winds then become east to southeast 5-
10 knots late in the afternoon. Moderate confidence.

Tonight...VFR. Southeast or south winds less than 10 knots, becoming
light and variable or locally calm. Moderate confidence.

Outlook...

Friday and Saturday...VFR.

Sunday...Mainly VFR.

Monday...Times of sub-VFR conditions along with some showers and
thunderstorms possible.

&&

.MARINE...
The conditions are expected to remain below Small Craft Advisory
criteria through tonight. Northwest to northeast winds may increase
for a time today, then turn east to southeast this afternoon and
evening and also decrease some. Seas below 5 feet.

Outlook...

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

Rip Currents...

For today, north to northeast winds 10-20 mph will become east to
southeast later this afternoon and evening. Breaking waves in the
surf zone are expected to be 2-4 feet with a 7 second period. With
the onshore component of the wind and multiple swell groups
expected, will maintain a MODERATE risk for the development of
dangerous rip currents at all beaches.

For Friday, very similar conditions to Thursday so we will go with a
MODERATE risk for the development of dangerous rip currents for all
beaches once again.

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
AVIATION...Gorse
MARINE...Fitzsimmons/Gorse