Socastee, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

453
FXUS62 KILM 201812
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
212 PM EDT Sun Jul 20 2025

.SYNOPSIS...
Heat and humidity continue, thanks to the Bermuda high pressure
offshore. A weak cold front approaches the area Monday and
Tuesday, bringing increased chances for showers and storms.
Slightly cooler, drier air stops by late Tuesday and Wednesday,
before another warmup enters the picture by late in the work
week.

&&

.NEAR TERM /THROUGH MONDAY/...
For the rest of today, despite moderate to strong instability and
precipitable water values around 2-2.25", a lack of trigger should
keep convection isolated at best this afternoon, especially with
some lingering dry air in the mid-levels acting to choke incipient
updrafts. Nevertheless, with west-southwesterly flow into the sea
breeze, convergence along that boundary may be able to develop at
least a shower or two in the most favored spots, with a thunderstorm
not out of the question. In addition, more agitated cumulus seen in
visible satellite imagery near the Piedmont trough suggests isolated
convection may be able to pop across the Pee Dee region as well.

Tonight, the surface pressure gradient relaxes a little as the mid-
upper ridge axis shifts southwestward and the high pressure center
beneath it weakens somewhat. In addition, a surface trough axis
looks to shift over the forecast area during the night. Thus, while
steady southwest to west winds should continue for much of the
night, some areas may see periods of calm or light/variable winds at
times, with northwestern areas seeing light northwest or north winds
later in the night. Otherwise, expect mainly clear skies with some
passing high cirrus and lows in the mid-upper 70s to perhaps 80F
near the coast.

On Monday, a mid-level trough digging into the western Atlantic will
help to turn the flow aloft more northwesterly than westerly,
opening the door to convection originating from the higher terrain
shifting southeastward into the forecast area late in the day. In
addition, the lowering heights should permit greater convective
coverage over the forecast area in the isolated to scattered range,
with hi-res guidance suggesting the sea breeze will become active
during the afternoon as well, especially over the Cape Fear area.
Moderate to strong instability (2000-3000 J/kg of SBCAPE), high
pwats (2.0-2.25"), and DCAPE around 1000 J/kg suggest heavy
thunderstorms can be expected, one or two of which could produce
damaging winds. Weak effective shear of 10-15 kts will limit storm
longevity and organization, and deep-layer mean winds of 8-10 kts
will result in slow storm motions unless a strong enough cold pool
can develop and help to propagate storms more rapidly. This
possibility exists for storms coming out of the northwest late in
the day, but this carries low confidence as it will depend on how
storms which develop over the higher terrain evolve.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
Cold front shifting south across the region Tuesday
along with the parent mid level trough and height falls will lead to
another day for convection. There is a slight lean toward the south
with the boundary but fronts this time of year move slowly so
confidence is on the lower side for now. Column moisture remains
sufficient to warrant good chance to even likely pops in some areas
Wednesday. Temperatures should be somewhat cooler due to the front
and convective coverage Tuesday and Wednesday with highs in the
upper 80s. Overall anticipated lows have jogged upward with any 60s
seemingly gone replaced by more lower 70s.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Bermuda ridge is quickly back in place for the extended
forecast. The forecast trends toward lower pops more favored
along the coast with the sea breeze and during the afternoon
hours. Temperatures trend upward as well seemingly very similar
to the past couple of days with highs in the middle 90s and lows
well into the 70s. Confidence is increasing in the need for
heat related headlines once again during this time.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Visible satellite imagery indicates increasingly agitated cumulus
are growing amidst a very moist and unstable air mass. With a lack
of any distinct trigger, it will be hard to anticipate where any
convection might develop until a Cb is observed. Environmental
conditions should keep convection isolated and short-lived, with
slightly better chances for convection along the Cape Fear sea
breeze near KILM and within a confluence zone observed near KFLO.
Otherwise, VFR will prevail through the period. Despite winds
becoming light and variable tonight, or even calm at times,
subsidence and dry air aloft should inhibit fog growth beyond
transient MVFR mist. Otherwise, a surface trough shifting over the
area will lead to a period of north to northwest winds late tonight
into tomorrow morning before backing to westerly around midday.
Convection affecting a terminal carries the highest confidence
around KILM, but this should hold off until after 18Z.

Extended Outlook... A weak front will drift south toward the area on
Monday and shift through on Tuesday, resulting in increased chances
of SHRA/TSRA. These storms could result in some brief MVFR to IFR
conditions at the terminals. If the front is able to push far enough
south, then dry conditions would prevail at the terminals Wednesday
and Thursday; otherwise, daily chances for storms will continue
through Friday, with the best chances for any impacts at SC
terminals.

&&

.MARINE...
Through Monday...Steady southwest winds remain the story
through the period, although a surface trough pushing eastward
tonight should result in a period of westerly winds from late
tonight into Monday morning, before returning to southwesterly.
While wind gusts may reach 25 kts at times through late today, a
Small Craft Advisory is not expected. Otherwise, with the
pressure gradient easing up tomorrow, speeds should be
noticeably lower than today. Wave heights around 2-4 ft today
will subside tonight and hold around 2 ft tomorrow, with the
primary contributor being south-southwesterly wind waves with a
period around 5 sec, supplemented by a 1-2 ft southeasterly
swell with a period around 8-9 sec.

Monday Night through Friday...Some rare for July but not
unprecedented northeast winds will greet the marine community
early Tuesday with a front pushing south. Wind speeds will be
10-15 knots decreasing in magnitude Wednesday before a return to
the more standard onshore flow later in the work week. This is
followed by the return to more south/southwest winds in time.
Significant seas could see a few four footers with the northeast
flow later Tuesday but overall expect 2-3 feet outside of this.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Heat Advisory until 8 PM EDT this evening for NCZ087-096-099-
     105>110.
     Heat Advisory from 11 AM to 8 PM EDT Monday for NCZ087-096-099-
     105>110.
  Coastal Flood Advisory from 5 PM to 8 PM EDT this evening for
 NCZ107.
SC...Heat Advisory until 8 PM EDT this evening for SCZ017-023-024-
 032-033-039-054>056-058-059.
 Heat Advisory from 11 AM to 8 PM EDT Monday for SCZ017-023-024-
 032-033-039-054>056-058-059.
MARINE...None.

&&

$$

SYNOPSIS...ILM
NEAR TERM...ABW
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...ABW
MARINE...SHK/ABW