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000
FXUS61 KPHI 180153
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
953 PM EDT Wed Apr 17 2024

.SYNOPSIS...
High pressure continues to move offshore as a series of fronts and
low pressure systems affect the East Coast through the end of
the week. High pressure looks to return for the weekend and the
start of next week.

&&

.NEAR TERM /THROUGH THURSDAY/...
Stationary front looks likely to remain positioned more or less
from north central PA southeastard towards the southern end of
the Delaware coast. Northeast of the front, low clouds, patchy
mist and drizzle will predominate through Thursday, with some
patchy dense fog possible across coastal areas thanks to the
persistent onshore flow off the ocean. Primary low in the Great
Lakes will weaken as it hits the high to our northeast with
secondary developing along the stationary front and pushing
eastward into the ocean on Thursday. Main push of showers and
embedded t-storms riding over the cool surface will arrive
overnight, but with the stable low levels, main threat will be
some brief heavy rains and isolated lightning strikes. Bulk of
Thursday looks relatively dry, with some reduction in fog and
mist/drizzle as the day wears on thanks to the strong April
insolation and a slight movement of the stationary boundary
northeastward. That said, not expecting it to move much, so
lows for most of the region will be in the mid-upper 40s north
and east of Philly and low-mid 50s south and west, with highs on
Thursday near 50 north and east of Philly. South and west, temps
rapidly rise as one reaches and passes the maximum northeastward
push of the front, with highs near 70 in far southenr Delaware
and the Maryland Eastern Shore.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
Overall, the short term forecast remains largely unchanged. By
Thursday night, the weak coastal low will be shunted south and
eastward enough that surface high pressure can build in and briefly
shutoff the chances for showers. Lows Thursday night look to fall
into the 40s most everywhere across the region.

Following the brief respite from showers Thursday night, the next
mid-level wave approaches the region on Friday. Latest guidance
continues to indicate that the pre-existing high will be strong
enough to hold off any precipitation through the morning. However,
the approaching wave will eventually move in and bring yet another
cold front across the region with the opportunity for more showers.
Chances for showers begin to increase Friday afternoon and look to
peak Friday night. However, the front overall continues to look  to
be drier so chances for precip Friday night are now around 30-40
percent at most. Showers look to clear the region by late Friday
night/early Saturday morning. Temperatures will rise into the upper
50s to low 60s during the on Friday before falling into the upper
40s to low 50s Friday night.

High pressure begins to nudge in on Saturday as the cold front moves
offshore. With the exception of some lingering showers in the
morning along the coast, everyone should be dry on Saturday with
gradually clearing skies. Temperatures will get into the mid to
upper 60s.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
The back half of the weekend and into early next week looks rather
benign as high pressure continues to settle in on Saturday Night
with the front from Friday stalling to the south of the region. Long
range guidance is continuing to suggest that a system will slide by
just to our south Sunday Night into Monday along the boundary.
Depending on exactly how far south the front stalls, this would
potentially allow a few showers to leak back into the most
southern portion of the region Sunday Night. Most of the
deterministic guidance and ensembles keep the weak area of low
pressure far enough south for everyone to stay dry however, and
no mentionable PoPs are currently in the forecast. High pressure
begins to settle in for Monday/Tuesday with quiet weather
anticipated. Another system looks to come in around mid-week
with some showers, but guidance varies quite a bit beyond
Tuesday.

With the front to the south of the region though, temperatures will
likely be below normal through Monday, with highs in the upper
50s/low 60s and overnight lows in the upper 30s/low 40s.
Temperatures look to moderate for the middle of next week, with a
return to near normal temperatures.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas...

Tonight...Lowering to IFR/LIFR. SHRA and BR will develop
tonight, and cannot rule out a few TSRA. SHRA end late, but low
CIGs and BR will persist and keep IFR/LIFR conds across the
terminals. E winds 5 to 10 kt. Moderate confidence.

Thursday...IFR in the morning, gradually improving to MVFR in the
afternoon. NE winds 10 to 15 kt. Low confidence.

Outlook...

Thursday Night...Sub-VFR conditions likely (50-70%) with stratus
hanging around.

Friday through Friday Night...Sub-VFR conditions likely (50-70%)
with low clouds through most of Friday and scattered showers moving
in Friday Night. Conditions lift to VFR by late Friday Night as a
cold front comes through.

Saturday through Monday...VFR expected. Potentially gusty winds on
Saturday afternoon.

&&

.MARINE...
Sub-Small Craft Advisory conditions this evening, then onshore
flow increases over the ocean waters late tonight and Thursday.
SCA starts for far northern waters late tonight and expands
southward to Delaware waters by tomorrow night, with easterly
wind gusts up to 30 kts and seas 4-8 ft. Winds should stay
lighter on Delaware Bay, sub-SCA.

VSBY restrictions in fog and showers tonight, and then fog and light
rain and drizzle will persist through Thursday. Cannot rule out a
few thunderstorms tonight as well.

Outlook...

Friday...Small Craft Advisory conditions possible (30-40%) for
coastal waters north of Cape Henlopen as seas hover around 5 feet.
No marine headlines expected for the rest of the waters.

Friday Night through Monday...No marine headlines expected.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 6 AM EDT Friday for ANZ450.
     Small Craft Advisory from 6 AM Thursday to 6 AM EDT Friday for
     ANZ451.
     Small Craft Advisory from noon Thursday to 6 AM EDT Friday for
     ANZ452-453.
     Small Craft Advisory from 6 PM Thursday to 6 AM EDT Friday for
     ANZ454-455.

&&

$$

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