385
FXUS62 KILM 180532
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
132 AM EDT Wed Sep 18 2024

.SYNOPSIS...
Weakening low pressure will linger west of the area before
slowly moving northeast. Warm conditions with daily low chances
for showers and thunderstorms are expected Wed. A weak cold
front accompanied with scattered convection will bring more
seasonable temperatures in its wake near the end of the work
week and into the upcoming weekend.

&&

.UPDATE...
Sfc pg relaxed resulting in winds decoupling over a good portion
of the FA. May see a land breeze (NW) near the coast if the
broken blanket of stratocu and altocu mainly remains remains
west of the I-95 corridor. The extent of these cloud decks
eastward, even as they partially scour out, will help keep fog
from becoming too widespread or from vsby dropping to low from
the fog. Min temps look aok, just tweaks to the hourly T and TD
based on latest obs and trends.

The Minor coastal flooding along the immediate NC and SC Coasts
cancelled early due to readings having breached thresholds for a
slightly shorter time period than anticipated. The lower Cape
Fear river minor flooding to expire at 1 am Wed.

&&

.NEAR TERM /THROUGH TODAY/...
The area remains in the dry slot of former PTC8 through the period
as the system will move very little. The gradient is very weak and
the stage may be set for a little fog, though most guidance hints
that it`s only MVFR and only of aviation concerns. With the upper
low still to our west on Wednesday a few spokes of vorticity will
rotate through the area, mainly western zones. Guidance trended
up a bit with POPs but felt that values above 40 seemed too
high so capped values there given the dry air evident in WV
imagery. Also seeing some pretty paltry lapse rates so wouldn`t
be surprised if thunder becomes the exception and not the rule
despite the afternoon warming a few degrees above climo.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
A closed mid-level low will dissipate into a trough through the
period with enhanced vorticity in its vicinity, weak surface low
pressure migrating northeast. PWATs will stick above 1.5" with
decent instability in the afternoon as the low moves overhead. At
the same time, a sea breeze will be moving inland from the coast,
which should enhance rain chances primarily west of the coast.
Drier air will start to arrive Thursday night as flow becomes
northeasterly. Lows will be in the mid 60s with highs in the
lower 80s.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
The trough looks to stall to our NE where higher moisture and
enhanced vorticity will linger. The majority of rain, should
there be any, should stay offshore, but the shortwaves moving
around the trough axis could bring low rain chances towards the
coast through the long term period. Highs in the low 80s and
lower 70s with lows in the 60s.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Generally VFR with brief periods of MVFR/IFR possible.
Increasing cloud cover associated with the low pressure aloft
over the western Carolinas is making an already difficult fog
forecast even more troublesome. Latest trends on satellite show
this cloud cover expanding as it rotates north over most of the
terminals. The increase in cloud cover will arrive 07-09Z
across SC and a bit later across NC. Have scaled back on
fog/visibility restrictions counting on the clouds to limit fog
development. Confidence is on the low side though, as larger
breaks in cloud cover or clouds dissipating would lead to higher
potential for IFR/MVFR. Widespread VFR shortly after daybreak.

Diurnal convection will be a concern this afternoon and
evening, especially for inland terminals. Storms will generally
be diurnal in nature with coverage dropping off rapidly
approaching 00Z. Depending on rain/debris cloud tonight MVFR/IFR
fog is possible around the end of the TAF period.

Extended Outlook...Afternoon MVFR possible Thursday with
morning MVFR/IFR possible Thursday and Friday mornings.

&&

.MARINE...
Through Wednesday...A very light gradient left behind in the
wake of PTC8 making for gentle SW breeze across the waters. Seas
will continue to abate from the stirring up of the cyclone both
due to the light winds and the abating E swell energy from the
system.

Wednesday Night through Sunday...Southerly flow will become
stronger and NE through Thursday, but expected to stay sub-SCA
at this time. Waveheights will be 2-4 ft with a dominant
easterly 9-10 second swell and an increasing NE wind wave.

&&

.TIDES/COASTAL FLOODING...
High astronomical tides, excessive rainfall and lingering swell
from the prolonged onshore winds will lead to coastal flooding
with the morning high tides along the southeastern NC coast and
the lower Cape Fear River around and south of Wilmington. Water
levels should remain in the minor category and another round of
advisories is likely for this evening`s high tides, with the
coast of northeast SC likely being impacted this evening.

Other - Rip Currents:
Continued improving surf conditions affecting all beaches for
Wed. A slowly decaying easterly swell at 9+ second periods will
affect local beaches. However, for the Pender and New Hanover
County Beaches, the surf will remain conducive for a Moderate
rip Current Risk for Wed, especially in that 4 hr window
centered around low tide.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Coastal Flood Advisory from 6 AM to 10 AM EDT this morning for
     NCZ106-108-110.
     Coastal Flood Advisory from 8 AM this morning to 1 PM EDT this
     afternoon for NCZ107.
SC...Coastal Flood Advisory from 7 AM to 10 AM EDT this morning for
     SCZ054-056.
MARINE...None.

&&

$$

SYNOPSIS...LEW
UPDATE...DCH
NEAR TERM...MBB
SHORT TERM...LEW
LONG TERM...LEW
AVIATION...DCH
MARINE...MBB/LEW
TIDES/COASTAL FLOODING...ILM