281
FXUS62 KILM 171508 CCA
AFDILM

Area Forecast Discussion...CORRECTED
National Weather Service Wilmington NC
1108 AM EDT Sat May 17 2025

.SYNOPSIS...
Above normal temperatures near record highs are possible today.
A weak cold front, which may be accompanied by a few showers
and thunderstorms will move across the area tonight. Next week
will start out dry and warm with increasing rain chances Tuesday
and Wednesday ahead of a cold front. Drier and cooler
conditions return late next week.

&&

.UPDATE...
Decaying convection to the west expected to have little impact
on the area today, though isolated storms are possible. Overall,
going forecast has a good handle on latest expectations but did
make small tweaks to max T and winds. Still a warm day on tap
but perhaps a shade cooler with debris clouds moving in from the
west.

&&

.NEAR TERM /THROUGH TONIGHT/...
A strong system/cold front currently moving across the
Tennessee Valley and producing significant convection will
seemingly have little to work with later today and this evening
as it crosses our area. Overall pops remain minimal and if
anything near the coast later this afternoon for just a couple
of hours. The extensive cloud cover however seems to have taken
a toll on guidance with regards to high temperature guidance as
even the 90th percentile NBM numbers are trending downward.
Still if enough breaks in the cloud cover occur a site or two
could thread the needle and tie or break a record. The official
forecast has been trended downward as well.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
Front stalls in the area Sun and Mon as the surface boundary ends up
parallel to the flow aloft. There is a lone shortwave moving through
the zonal flow aloft on Sun, but the timing of the PVA ahead of it
is prior to peak heating. The best moisture/dynamics with the
shortwave pass to the south, further decreasing the potential for
any affects locally. Deep, dry and and mid-level capping (post wave
subsidence) will keep the region dry Sun with highs 7-10 degrees
above normal. Deep westerly flow will keep the sea breeze pinned
near the coast, ensuring much of the area remains on the warm side.
Somewhat cooler air follows the passage of the shortwave, which
helps push the stalled front a little farther south. This drops Sun
night lows close to normal.

Front lingers south of the area Mon morning but then starts to work
its way north during the next. Flow aloft starts to amplify as weak
5h ridge expands north over the Deep South. Shortwave topping the
ridge Mon induces weak surface cyclogenesis which then helps lift
the front across the area. Not enthused about rain chances on Mon.
Forecast soundings show a lot of dry air below 500mb and even with
another day of temperatures well above normal the abundant dry air
will keep SBCAPE AOB 200 J/kg. Even the development of a resultant
sea breeze will not be enough to generate any convection. Guidance
does suggest potential for MCS development Mon evening in the
western Carolinas which then migrates east-southeast. If this
feature does develop it would be in a weakening state as it
approaches the local area. The environment doe not improve much from
earlier in the day, the MCS will bring an increase in mid-level
moisture with it, but the lack of surface based instability and
marginal laps rates will likely be the end of any weak convection
trying to move in from the northwest.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Front lingers north of the local area Tue/Wed as stacked low takes
shape across the central CONUS. Honest rain chances Tue, although
limited moisture will keep coverage in the chance realm. Rain
chances ramp up Wed with much more moisture in the region as a cold
front approaches. Precipitable water surges to almost 2" which is
near 170% of normal, for comparison Tue is "only" about 130% of
normal. Frontal convergence and divergence aloft as the 5h trough
approaches from the west will further enhance the environmental
parameters. Storms will be moving at a good clip and higher LCLs
will limit warm cloud layer depth despite a freezing level near 14k
ft. Not really a flood kind of event, but given the low level dry
air, inverted V sounding, high freezing layer and DCAPE around 700
J/kg cannot rule out a damaging wind gust, but widespread severe
seems unlikely, especially with a low level jet struggling to hit
30kt. Cold front moves across the area Wed evening, lagging the
convective line, and is followed by a much drier and cooler air
mass. Although there will be a cutoff low over the Northeast or Mid-
Atlantic region the abundance of dry air will limit any potential
shower activity associated with the base of the 5h trough and any
associated shortwaves. The week ends dry with temperatures below
normal.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions expected through the period. Convective coverage
associated with the system moving across later today/overnight
continues to look paltry at best so no significant impacts
expected.

Extended Outlook...Mainly VFR conditions are expected through
the period.

&&

.MARINE...
Through Tonight...
Southwest winds on the increase this morning as the gradient
increases ahead of a significant cold front to the west. Speeds
will increase to an eventual 15-20 knots this afternoon and
evening. Significant seas will be 2-4 feet for most of the day
and increase to 3-5 feet this evening with the slightly stronger
winds. Elements should remain below headline criteria.

Sunday through Wednesday...
Winds will be on the low end of the 10-15 kt range for much of
the forecast. Front stalls in the area, weakening the gradient
and leading to changeable wind direction. The daily sea breeze
will have the biggest impact on the wind field Sun-Tue. On Wed
an approaching cold front enhances the gradient with speeds
rising into the 15-20 kt range in the afternoon and evening.
Seas will run 2-3 ft through the first part of next week before
the increase in southwest winds starts building seas. It is
possible headlines will be needed for seas later Wed given the
12+ hour duration of enhanced winds. Seas will be a mix of a
south to southwest wind wave and southeast swell with the wind
wave becoming much more dominant Wed.

&&

.CLIMATE...
High temperature records may be challenged again today as
anomalously warm air overspreads the region ahead of a cold front.
Record highs for our four climate sites are as follows:

Wilmington, NC:      92F (1960, 1990)
Lumberton, NC:       96F (1941)
Florence, SC:        93F (1977)
N. Myrtle Beach, SC: 92F (1941)

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...None.
SC...None.
MARINE...None.

&&

$$

SYNOPSIS...ILM
UPDATE...31
NEAR TERM...SHK
SHORT TERM...III
LONG TERM...III
AVIATION...SHK
MARINE...III/SHK
CLIMATE...ILM