547
FXUS61 KPHI 141007
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
Issued by National Weather Service Baltimore MD/Washington DC
607 AM EDT Fri Aug 14 2026

.WHAT HAS CHANGED...
No major changes. Showers approaching from Ohio should weaken
and dive south for the most part through midday.

&&

.KEY MESSAGES...
1. Cold front continues to sink south today, bringing gradually
improving conditions with high pressure overhead Saturday and
the first half of Sunday.

2. Unsettled weather returns Sunday into Monday.

&&

.DISCUSSION...
KEY MESSAGE 1...Cold front continues to sink south today,
bringing gradually improving conditions with high pressure
overhead Saturday and the first half of Sunday.

The stationary front that has lingered across the region the
last few days will continue to sink south as a cold front today,
allowing gradually improving conditions to filter in. Cooler
temperatures and lower humidity will begin to arrive today, and
especially Saturday.

Some showers are possible late today into tonight as the cold
front finally shifts far south enough to allow surface high
pressure to be overhead Saturday and into early Sunday. The
forecast Saturday looks to be the driest, coolest, and least
humid day through the weekend. That being said highs on Saturday
are only a few degrees lower than Friday, so it won`t be
dramatically cooler.

High pressure will not last, however, and shift offshore
Sunday, bringing return flow back across the region, allowing
temperatures to creep back up into the mid to upper 80s and the
humidity to return. The morning will be largely dry with chances
for rain returning by the afternoon.


KEY MESSAGE 2...Unsettled weather returns Sunday into Monday.

The next storm system arrives Sunday into Monday as a surface
low moves across the Great Lakes, Ohio Valley, and eventually
the Mid-Atlantic, bringing the chance for showers and
thunderstorms.

The biggest change with previous guidance is the spread in the
timing of precipitation. There are some models that show
precipitation moving in as early as 06Z to 12Z Sunday Morning.
That being said, there are still a few models not showing rain
move in until the afternoon. The net result of this uncertainty
is that there are PoPs in place from late Saturday Night all the
way through Monday. This long period of rain mention is an
artifact of the differences between models in the timing, but
I don`t expect rain to occur for that entire period.

Regardless of the timing, the primary threat at this point is
heavy rain leading to flash flooding. Global guidance shows
PWAT values surging back into the 2" range, increasing the
potential for heavy downpours within any thunderstorms that
develop. As a result, WPC does have much of the Northeast and
Mid-Atlantic in a Marginal risk in the Excessive Rainfall
Outlook.

Depending on the timing of the storms, some instability may be
in place to support a severe potential. Latest guidance is a bit
more robust with upper-level forcing for ascent as well as shear,
probably linked to some convectively enhanced features of the
incoming trough which are tough to resolve a few days out. At
this point, it remains too early to lock down any specifics for
severe and flash flood, but we will need to monitor the
potential over the next several days.

&&

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

Today...VFR. W wind around 10 knots. Sea breeze for ILG, ACY,
MIV during the afternoon (SE winds).

Tonight...Mainly VFR. Light NE winds. Sct tstm possible.

Outlook...

Saturday through Sunday Morning...VFR. No significant weather.

Sunday Afternoon through Monday...Sub-VFR conditions likely (60-70%)
at times with widespread showers and a few embedded thunderstorms
anticipated.

Tuesday and Wednesday...VFR conditions expected.

&&

.MARINE...
No prevailing marine hazards expected through today.

Outlook...

Today through Sunday...No marine headlines expected.

Sunday Night through Monday...SCA conditions possible (30-40%) as
seas near 5 feet and southerly wind gusts near 25 kt.

Tuesday...No marine headlines expected.

Rip Currents...

Generally tranquil conditions expected at the beaches through
Saturday. Winds turn onshore but will be light - under 10 MPH.
An 8 to 10 second period swell will also be present, but
breaking waves should be 2 feet or lower. This will result in a
LOW risk for rip currents at all beaches for Friday and
Saturday.

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

&&

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

&&

$$

DISCUSSION...PHI/DHOF
AVIATION...PHI/DHOF
MARINE...PHI/DHOF