-- Discussion containing changed information from previous version are highlighted. --
400
FXUS62 KILM 190541
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
141 AM EDT Thu Sep 19 2024

.SYNOPSIS...
A cold frontal passage and the passage of an upper level trof
will result in a chance for showers and isolated thunderstorm
thru Thu. Slightly cooler and drier weather will accompany
persistent north-northeasterly winds Fri thru the weekend as
high pressure builds in from the north.

&&

.UPDATE...
Coastal flooding has come to an end along the immediate coast
and advisories for all area beaches have expired. There have
been some slight changes to PoP as showers continue to persist
across portions of southeastern NC and west of the I-95
corridor. Previous update remains valid in regards to the
ongoing synoptic setup.

Previous update... A sfc cold front dropping southward and a
closed low opening up into a trof that will slide to the coast
by daybreak Thu. Both will maintain the chance for showers and
isolated storms across the FA overnight, with the main thunder
threat likely over the waters overnight. Kept fog patchy given
various cloud decks across the FA. This may also require a
degree or 2 upwards adjustment for tonights lows.

&&

.NEAR TERM /THROUGH TODAY/...
Upper level reflection of former PTC8 now more open and less
impressive. No surprise then that convection has been
hard-pressed to produce lightning. Guidance is in good
agreement in keeping this so as well as confining coverage to
western half of the CWA. Expect a diurnally-driven downward
trend in coverage overnight, perhaps to zero for a time. Patchy
fog is possible overnight especially in areas that see rain.
Slightly better coverage of storms tomorrow but very poor lapse
rates will keep lightning to a minimum and rainfall amounts
light while we see temperatures similar to those of this
afternoon.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
Best rain chances will be near the coast at the start of the
period as low pressure departs to our northeast. High pressure
will build in from the west where the forecast now remains
mostly dry. Some isolated showers and storms could form along
the sea breeze Friday afternoon but they should remain shallow
and chances of rainfall accumulation >0.05" will be low. Highs
in the low to mid 80s with lows in the low to mid 60s.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Guidance now keeps the offshore low far to our northeast, which
diminishes chances of enhanced forcing clipping our area. The
period is now looking mostly dry with some temperature
complications due to ridging high pressure. Depending on how
quickly the high pressure moves in, temperatures could drop into
the 70s by Sunday staying seasonable into early next week. The
coolest day is looking to be Monday currently.

&&

.AVIATION /05Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
Currently VFR reported at all sites although starting to see
some hints of fog inland. Cloud cover, a combination of debris
cloud from evening convection and clouds associated with low
pressure aloft, continue to linger over the region this morning.
Clouds complicate the fog forecast, as do boundary layers winds
a kt or two higher than last night. Expect to see development of
MVFR along the coast as clouds thin/clear out with IFR being
more possible inland, especially across inland SC. This is an
area where more rain fell yesterday afternoon. However, given
the cloud cover confidence in development of IFR a few hours
before sunrise is low.

Widespread VFR returns between 13Z and 14Z with another round
of afternoon and evening storms. Higher coverage of storms
around NC terminals, but SC terminals still have potential to be
affected by storms. MVFR/IFR potential late in the TAF period,
but as is the case this morning, lingering debris cloud could
limit fog potential.

Extended Outlook...MVFR/IFR possible Friday morning.
-- End Changed Discussion --

&&

.MARINE...
Through Thursday...Light SW to at times variable winds early
in the period with wave energy that continues to abate. A weak
boundary turns flow to the north on Thursday as mainly swell
waves of 9 seconds remain in the 2-3 ft range.

Thursday Night through Monday...N to NE flow will remain
dominant through the period due to departing low pressure. Wind
speeds will be generally around or above 10 kts with strongest
wind speeds (15- 20 kts) expected Sunday into Monday due to
ridging high pressure from the north. Waveheights generally 2-4
ft with building 5 footers towards the end of the period due to
increasing N-NE swells.

&&

.TIDES/COASTAL FLOODING...
High astronomical tides during this full moon cycle will lead
to bouts of minor coastal flooding during both the daytime and
night time high tide cycles into and likely thru the upcoming
weekend. This includes the immediate coasts of both Northeast SC
and Southeast NC Coasts.

The lower Cape Fear River will also experience minor coastal
flooding during each successive high tide cycle into and
possibly thru the upcoming weekend. Both high astronomical tides
and the runoff from the heavy rains early in the week working
its way downstream.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
NC...None.
SC...None.
MARINE...None.
-- End Changed Discussion --

&&

$$

SYNOPSIS...ILM
UPDATE...DCH/21
NEAR TERM...MBB
SHORT TERM...LEW
LONG TERM...LEW
AVIATION...III
MARINE...MBB/LEW
TIDES/COASTAL FLOODING...