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196
FXUS61 KPHI 040145
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
945 PM EDT Mon Jun 3 2024

.SYNOPSIS...
Surface high pressure over the area slides offshore by
Wednesday and moves out to sea on Thursday. A weak disturbance
passes through the region tonight, and then low pressure passes
through on Thursday. An upper trough sets up over the Northeast
for the end of the week and through next weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --
Showers and isolated thunderstorms are now dwindling. For the
rest of tonight, high pressure begins to slide in from the
north, resulting in a weak onshore flow developing. Some fog is
expected, mainly in areas near/along the coast. Otherwise, it
will be a quiet night with temperatures in the low to mid 60s.

For Tuesday, a ridge axis slides overhead with high pressure in
control at the surface. Should be a nice and quiet day overall,
but a some lingering instability may not have been cleared from
parts of the Delmarva where a few pop-up storms may occur down
in the Maryland eastern shore, so have bumped up pops there.
With the weak onshore flow, areas near the coast will stay in
the 70s. Elsewhere, expect 80s.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
Onshore flow Tuesday night may bring more fog especially near
the coast. Otherwise, upper level ridge over the area Tuesday
night will flatten out on Wednesday. Meanwhile, a nearly
vertically stacked area of low pressure over central Canada will
dig down into the upper Midwest and Great Lakes. A trough
develops out ahead of this, and weak surface low pressure
develops over the Mid- Atlantic and Northeast. Scattered showers
and thunderstorms develop by Wednesday afternoon, with showers
becoming likely late in the day for the eastern shores of
Maryland. Dew points rise well into the 60s, so there could be a
locally heavy downpour or two in the afternoon.

Low pressure then passes over the area Wednesday night,
departing Thursday afternoon. Will carry likely PoPs for the
region Wednesday night, tapering to chance Thursday. There may
be enough instability for thunderstorms as well, so will keep
chance for thunderstorms.

Highs will be in the lower 80s both Wednesday and Thursday,
though Thursday may be a degree or two warmer, depending on when
rain ends and skies clear out. But it will be fairly humid with
dew points well in the 60s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Surface low pressure moves out to sea Thursday evening. A cold
front approaches from the northwest as a closed upper low builds
down into the Great Lakes, Ohio Valley, and Northeast. This
closed low will park over the Northeast through the weekend,
possibly starting to depart on Monday.

Several waves of shortwave energy will rotate through the
trough. While this timeframe does not look to be a washout,
there will be chances for showers and thunderstorms each day.
Best chances for convection will be during the afternoon hours,
when peak heating will allow for highest instability.

High temperatures during this period will generally be at or
just shy of normal, topping off in the upper 70s to around 80.
Lows will be in the 50s to around 60.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Rest of Tonight...Isolated showers dwindling. VFR to start.
Some patchy fog could bring visibility restrictions down to IFR
overnight. With onshore flow, this looks most likely to occur at
the NJ terminals. Winds generally light and variable 5 kt or
less, though an east direction will be favored. Moderate
confidence overall.

Tuesday...Any restrictions lift back to VFR by 14z-15z. VFR
through the day. Winds out of the east around 5 kt. High
confidence.

Outlook...

Tuesday night...Low clouds/fog from easterly flow could result
in IFR conditions developing late, especially for terminals
closer to the coast.

Wednesday through Thursday...Restrictions likely in
SHRA/scattered TSRA.

Friday through Saturday...Primarily VFR, but scattered
SHRA/TSRA could result in brief restrictions.
-- End Changed Discussion --

&&

.MARINE...
Areas of fog possible overnight into early Tuesday may
necessitate a dense fog advisory on the waters; otherwise,
isolated showers this evening should dwindle and are not
expected to redevelop on Tuesday. Winds out of the
east/southeast at 10 kt or less with seas around 2 feet.

Outlook...

Tuesday night...Sub-SCA conditions. Fog possibe.

Wednesday through Thursday...Primarily sub-SCA conditions,
though occasional gusts to 25 kt are possible. VSBY restrictions
likely in showers, and scattered thunderstorms possible as
well.

Friday through Saturday...Sub-SCA conditions. Scattered showers
and thunderstorms, mainly during the daytime hours.

Rip Currents...

A LOW risk for the development of rip currents is in place for
Tuesday. Winds will be on onshore, but only around 10 MPH, with
1-2 foot waves and a short to medium period, resulting in the
low risk.

For Wednesday, winds increase to 10-15 mph but winds will be
less directly onshore. Combined with continuing 1 to 2 foot
waves and short to medium period keeps the overall risk for rip
current development at LOW.

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

Rip currents occur often in the vicinities of jetties and
piers. Utilize any guarded beaches if venturing out into the
water.

&&

.TIDES/COASTAL FLOODING...
With the return of sustained onshore flow and the approaching
New Moon on Thursday, there is also a return of the threat for
tidal flooding for much of our coastal region. The threat will
begin with the evening high tide on Tuesday, though primarily
spotty minor flooding is expected as the onshore winds will be
relatively weak around 10 mph. Cannot completely rule out some
widespread minor flooding if winds are a bit stronger. For
Wednesday and Thursday, the threat for widespread minor flooding
looks to increase as winds strengthen on Wednesday then turn
and become shore parallel on Thursday, potentially trapping
water along the coast. As of now, no coastal flooding headlines
have been issued but we will continue to monitor the coming high
tides and make adjustments to the forecast accordingly.

Overall, the threat for tidal flooding appears to be lower along
the Chesapeake Bay than elsewhere in the region but by the
early morning high tide Thursday, water levels may also approach
spotty minor.

&&

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

&&

$$

SYNOPSIS...MPS
NEAR TERM...Hoeflich/RCM
SHORT TERM...MPS/RCM
LONG TERM...MPS
AVIATION...Hoeflich/MPS/RCM
MARINE...AKL/Hoeflich/MPS/RCM
TIDES/COASTAL FLOODING...AKL