-- Discussion containing changed information from previous version are highlighted. --
129
FXUS61 KPHI 121347
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
947 AM EDT Wed Jun 12 2024

.SYNOPSIS...
Weak surface high pressure controls the region through Thursday
night. A cold front approaches from the northwest Thursday
night into Friday and looks to cross through later Friday into
Friday night. High pressure builds in thereafter and holds
influence over the region into the beginning of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
As of 9:45am...Forecast remains on track. Made minor adjustments
to temps/wind grids basis ongoing observations. Otherwise,
previous discussion is below:

As today wears on, upper low will continue pulling away as
upper ridging builds in. There will be a warm front moving
across the region to usher in the warmer air. The front, mostly
aloft, will be accompanied by mainly mid and high clouds, so
not expecting a pure sunny day... more likely partly to mostly
sunny, as the main push of clouds with the front likely moves
across during the late morning into early afternoon. Regardless,
the return of sun and passing warm front should push temps back
to near 80 for much of the region.

Tonight, ridging and warm advection continues aloft. Thus,
expect temps to stay a few degrees warmer despite less cloud
cover, with upper 50s to low 60s for most.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Weak surface high pressure controls the region Thursday and
Thursday night. Thursday night and early Friday, a cold front
from the northwest approaches. This cold front looks to cross
through Friday afternoon into Friday evening. Afterwards,
surface high pressure begins to build back in.

We will be looking at a dry forecast for Thursday and Thursday
night with surface high pressure in control. PoPs will increase
from the northwest with time Friday; highest PoP expected
between 2PM Friday and 2AM Saturday due to the further approach
and passage of the cold front.

We will have to keep an eye on the forecast regarding this cold
front for later Friday into Friday night. The front is
currently forecast to cross through during the ideal time for
potential severe weather after what looks to be a decent day of
solar heating. Between latest regional and global guidance,
1000-2000 J/kg of CAPE can be noted with around 35-40 kts of 0-6
km shear in most model soundings. In addition, noting fairly
moist and tall CAPE profiles with PW values between 1.5-2.0
inches; excessive rainfall may be a concern.

Decent warm air advection takes hold Thursday through Friday.
Most locations will be looking at highs in the mid to upper 80s
for Thursday while the areas near the coast and Poconos see the
upper 70s to low 80s. Temperatures are forecast to be even
warmer for Friday. Most areas will see the upper 80s to low 90s,
the immediate coastal areas and Poconos seeing the upper 70s to
mid 80s.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
An upper-level ridge centered over/near the Mississippi River
Valley Saturday will progress eastward and build with time. This
ridge will look to be centered over the southeastern CONUS for
Sunday, only continuing build with time. Monday onwards, the
strong ridge looks to utterly dominate over the eastern CONUS;
higher heights continuing to build over the northeastern CONUS
and northwards of it going forwards. Most ensembles suggest this
ridge could even dominate over the region into the end of week.

At the surface level, high pressure looks to dominate over the
region Saturday and Sunday into Monday. Surface high pressure
will look to be centered over/near the Great Lakes region
Saturday and will move generally eastward with time. Though the
surface high is forecast to shift offshore Monday, guidance
suggests the high will still influence the region into at least
Tuesday.

Dry forecast for the weekend with some slight shower potential
during the evening time frames Monday/Tuesday thanks to some
potential shortwave energy. Main story of the long term will be
the heat in the beginning of week. Ensembles suggest anomalous
heights around 588-592 dam over the region; surface temperatures
will likely run above average starting Monday and Tuesday. It
remains too early to really discuss any potential for heat
headlines at this time, but rest assured, it will feel hot.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

VFR overall expected through tonight. Winds mainly 5 kts or
less through tonight, from a northerly or westerly direction,
except at KACY where a sea breeze is likely by this afternoon.
High confidence.

Outlook...

Thursday...VFR with mostly clear skies. No significant weather
expected.

Friday through Friday night...Sub-VFR conditions possible with
a chance of thunderstorms during the afternoon/evening.

Saturday through Sunday...VFR with mostly clear skies. No
significant weather expected.

&&

.MARINE...
No marine headlines through tonight. Winds northerly to
westerly generally below 15 kts and seas of 1-2, occasionally up
to 3 feet.

Outlook...

Thursday through Friday night...SCA conditions possible
Thursday into Friday due to winds gusting up to 20-25 kts and
seas of 3-5 feet. Fair weather expected through Thursday night
with a chance of thunderstorms later Friday and Friday night.

Saturday through Sunday...No marine headlines expected. Winds
up to 10-15 kts with seas 2-4 feet. Fair weather.

Rip Currents...

A Low risk for the formation of dangerous rip currents
continues through Thursday. Southerly winds will only have a
small component onshore for most of the coast. Additionally,
expecting more short period, wind driven waves.

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

&&

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

&&

$$

SYNOPSIS...Wunderlin
NEAR TERM...DeSilva/RCM
SHORT TERM...Wunderlin
LONG TERM...Wunderlin
AVIATION...DeSilva/Fitzsimmons/Johnson/RCM/Wunderlin
MARINE...DeSilva/Fitzsimmons/Johnson/RCM/Wunderlin