881
FXUS61 KPHI 071331
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
931 AM EDT Sun Jul 7 2024

.SYNOPSIS...
The weak stationary front in our region is expected to dissipate
through tomorrow. The next weak front arrives Tuesday night or
Wednesday, followed by another cold front late in the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 9:30am...Only made minor changes to the forecast grids
mostly to temps, dew points and sky conditions basis current
observations. Previous discussion remains below:

Today, the more humid airmass will be across the SE areas while some
drier air remain to the NW. There are several boundaries in place
and a sea-breeze will develop too. Most of the CAMs are showing
some scattered shower/tstms activity today, especially for
Delmarva and Srn NJ. We`ll keep low chance or slight chc pops
for these areas today and a dry fcst for the southern Poconos
and north NJ. It`ll be another hot day, but not as much as the
past few days and overall the humidity will be a tick lower.
Consequently, we will not have any heat related flags for today.
Highest apparent temperatures will be in the upper 90s. It
would still be advised to take it easy if you will be
working/playing outside in the sun.

The convective activity will diminish later this evening and the
later part of the night should be dry. Patchy fog will develop,
especially in areas that receive rains today. Lows will remain very
mild with mostly low/mid 70s expected. Light winds overnight.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
The hot and humid conditions continue, with increasing chances
for storms on Tuesday.

The dominant feature in this period is expected to be the broad
ridge situated to our east in the low, mid and high levels of
the atmosphere. Consequently, we`ll keep southerly flow
resulting in continued very warm conditions. How humid it will
be though, is far more uncertain. Some guidance suggests that
the surface dew points though mix down more Monday afternoon,
and if this occurs then the peak heat indices would tend to stay
below advisory criteria for the entire area. By Tuesday,
humidity may be on the increase, but so too is cloud cover,
which could be the limiting factor for heat index values.

As for storm chances, a mid level short wave ridge on the back
side of the main high should be in place over our region which
will likely limit any storm development through the day. By
Tuesday, the ridge will be out of our region, with mostly zonal
mid and upper level flow. While there won`t be much mid and
upper level forcing, there should be enough low level
convergence along the frontal boundary in our region for
scattered storm development.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Summary...Thunderstorm chances remain in place through the end
of the week as the pesky front remains very close to our region.
The remnant low of Beryl is currently forecast to remain
northwest of our region through this period, though moisture
associated with the system, could move into our region.

Wedensday and Thursday...As mentioned above, most guidance is
depicting the remnant low of Beryl to lift into the Great Lakes
region. It should be noted however, this is one of the first
model cycles where there is relatively good agreement on the
track of the remnant low, so will have to watch the trends
closely to see if this continues. Even if the center of the low
stays well away from us, moisture advection on the eastern side,
interacting with the front moving into our region means
increasing chances for showers and storms across our region.
Given that the best upper level forcing will stay northwest of
our region, not sure storm coverage will be widespread yet.

Friday and Saturday...a trailing mid level short wave trough is
depicted in most deterministic models as approaching our region
through this time. This will lead to another chance for showers
and storms across the region, especially if the front on
Thursday stalls over our region, providing a focus for low level
convergence.

&&

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

TODAY...VFR expected but scattered showers/tstms may affect
KMIV/KACY this afternoon. MVFR/IFR for a short period possible
with any TSTM. Low confid in SHRA/TSRA occurrence. NE/N winds
this morning then S/SE winds developing. Overall Low/medium
confid.

TONIGHT...VFR expected. Could be some fog for KMIV/KACY. Light
winds. Medium confid.

Outlook...

Monday...VFR with no significant weather expected.

Tuesday through Thursday...periods of MVFR or lower conditions
possible with any thunderstorms.

&&

.MARINE...
Weak flow aloft will keep rather tranquil conditions across the
waters today and tonight. Winds will favor S/SW but will turn
onshore this afternoon. There will be scattered showers and a
few thunderstorms developing today which will carry into the
early evening. Locally higher winds and seas in the vicinity of
thunderstorms.

Outlook...

Monday: Winds and seas should stay below SCA criteria.

Tuesday and Wednesday: Winds and seas should stay below SCA
criteria. However, some thunderstorms especially each afternoon
and evening could produce locally gusty winds.

Thursday: Seas on the ocean waters could be near or above 5 ft
through the later half of the day. Additionally, there is
another chance for storms producing locally gusty winds.

Rip Currents...

Today, winds will be rather light and mostly onshore. Speeds will
be less than 10 knots much of the day. Gentle seas with these
winds will favor a LOW risk for the development of dangerous
rip currents at the Jersey Shore and for Delaware.

LOW risk is also expected for Monday.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...Air Quality Alert until 11 PM EDT this evening for NJZ008>010-
     012>015-017>020-026-027.
DE...None.
MD...None.
MARINE...None.

&&

$$

SYNOPSIS...Gorse/Johnson
NEAR TERM...DeSilva/OHara
SHORT TERM...Gorse/Johnson
LONG TERM...Gorse/Johnson
AVIATION...DeSilva/Johnson/OHara
MARINE...Johnson/OHara