462
FXUS61 KPHI 031044
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
644 AM EDT Fri May 3 2024

.SYNOPSIS...
High pressure builds into New England with onshore flow setting up.
A series of cold fronts approaches for the weekend, with the second
(and stronger of the two) front stalling out nearby by early next
week. The stalled front lifts north as a warm front at some point in
the Tuesday/Wednesday timeframe, bringing a return to above normal
temperatures.

&&

.NEAR TERM /THROUGH TONIGHT/...
The marine stratus never quite made it to the coast and moved
onshore. Satellite images indicate a disturbance, perhaps an
area of NVA as indicated by the NAM, washing out the marine
layer as it approaches the coast. Some patchy fog has developed,
but that should dissipate over the next hour or so.

The cold front has sagged south of Delmarva, and the cooler and
drier airmass will also continue to sag south. Onshore flow
should keep dew points up in the low to mid 50s along the coast
and in the coastal plain.

High pressure builds into New England. Onshore flow will result
in a much cooler airmass spreading into the region. Highs will
still be a few degrees above normal, but much colder compared to
Thursday, topping off in the mid to upper 60s for most of the
region, and in the upper 60s to low 70s for far western portions
of the forecast area. For coastal areas, onshore flow will keep
temperatures in the 50s.

Low pressure approaches from the west tonight. Most of the
region will remain dry as high pressure hangs tough along the
coast, but some showers may move into far western portions of
the forecast area prior to daybreak Saturday.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Not the best weekend ahead weather-wise but not necessarily terrible
either. A weakening cold front will approach on Saturday, with some
showers moving through ahead of it. Best chance to see showers will
be west of the I-95 corridor, but can`t rule out some light rain
across the area. Otherwise, it will be cloudy and cool with a steady
onshore flow. Temperatures will be in the upper 50s/low 60s. With
the maritime airmass in place, not expecting much in terms of
thunderstorms as it should remain rather stable.

Showers become more widespread by Saturday Night through Sunday
Night as a stronger cold front approaches from the west. Highest
PoPs are concentrated in the Sunday morning timeframe. Some elevated
instability could move in for Sunday afternoon/evening but not
expecting any severe weather, and just some rumbles of thunder mixed
in with passing showers. The maritime airmass will continue to have
a grip on the region, though flow turns a bit more southerly in
southern Delmarva. The result will be another day in the upper
50s/low 60s for most, with upper 60s/70s in southern Delaware and
along the southern Eastern Shore.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Unsettled conditions are expected for most of next week as a
boundary stalls out over the region. Rain chances are in the
forecast each day during the week as several waves of low pressure
are expected to ride along the boundary. Each day won`t be a washout
by any means, and PoPs are generally around 20-40% Monday/Tuesday,
with the highest coming in the afternoon. Not much instability will
be present, with the threat of any thunderstorms/severe weather
being low. Temperatures both days will be in the mid to upper 70s,
with some 80s possible on Tuesday.

The boundary looks to lift north by Tuesday in the form of a warm
front, putting the region in the warm sector. Looking at a period of
above normal temperatures for Wednesday/Thursday with upper 70s/low
to mid 80s anticipated. A few shortwaves will move through, which
will spark off some showers and thunderstorms, mainly in the
afternoon/evening both days. More instability will be present, so we
will have to watch this window, though too early to tell if/how
impactful any convection will be.

&&

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

Today...Fog and stratus never quite developed, so will carry VFR
conditions for all terminals except for KACY, where MVFR/IFR
CIGs are still expected to develop today. E winds 8 to 12 kt,
but 10 to 15 kt with 18 to 23 kt gusts at KACY. Moderate
confidence.

Tonight...VFR for most of the night for most of the terminals,
lowering to MVFR at KACY/KMIV late. E winds 5 to 10 kt. Low
confidence.

Outlook...

Saturday...Mainly VFR. Some MVFR restrictions possible later in the
day especially at KRDG/KABE.

Outlook...

Saturday Night...Restrictions expected with steady rain moving
through, with CIGs as low as IFR possible.

Sunday...Restrictions expected with showers/low clouds moving
through. CIGs as low as IFR possible.

Sunday Night...Restrictions possible with 40-60% chance of showers
and 15-25% chance of thunderstorms.

Monday through Tuesday...Primarily VFR though some restrictions
possible with any showers. 20-40% chance of showers through this
period.

&&

.MARINE...
A tightening easterly pressure gradient will develop on the waters
today, and E winds will increase to 15 to 20 kt with gusts up to 25
kt for most NJ and DE ocean waters. Seas will build to around 5 ft.
Will go ahead and hoist a Small Craft Advisory for all ANZ451-455
from 8am to 4pm. Sub-SCA conditions for DE Bay today and tonight.
Sub-SCA conditions for the ocean tonight.

Patchy fog expected on the ocean waters today and tonight with 1
to 3 NM VSBYs.

Outlook...

Saturday through Tuesday...No marine headlines anticipated.
Showers/thunderstorms possible on the waters Sunday through Sunday
night.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 4 PM EDT this afternoon for
     ANZ451>455.

&&

$$

SYNOPSIS...Hoeflich
NEAR TERM...MPS
SHORT TERM...Hoeflich
LONG TERM...Hoeflich
AVIATION...Hoeflich/MPS
MARINE...Hoeflich/MPS