Mc Coll, South Carolina Weather Forecast Discussion

841
FXUS62 KILM 051811
AFDILM
Area Forecast Discussion
National Weather Service Wilmington NC
211 PM EDT Fri Sep 5 2025
.SYNOPSIS...
Temperatures above normal will continue through Saturday. A cold
front will bring increased rain chances and slightly cooler
temperatures on Sunday. Cooler weather arrives next week with
periods of unsettled weather possible, especially along the
coast.
&&
.NEAR TERM /THROUGH SATURDAY/...
Latest surface analysis shows an old frontal boundary well offshore
of the area, while the Bermuda high continues to more moisture into
the area. Dewpoints have gradually come up across the area, thanks
to the southeasterly flow. This will aid in slightly warmer low
temperatures tonight, generally in the upper 60s to lower 70s. Calm
winds tonight may lead to some patchy fog before sunrise Saturday
morning.
Saturday, a cold front will start to make its way through
Appalachia, not making it to the coast just yet. Warm onshore flow
will continue to pump in more moisture, with dewpoints ramping up
into the 70s by late in the afternoon. Pre-frontal warming allows
highs to shoot up in the lower 90s inland, upper 80s at the coast.
Most of our stations haven`t recorded the 90s since mid-late August,
so it looks like that streak will come to an end.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
As a mid-level shortwave trough ejects from Lake Erie northeastward
along the international border over Saturday night, a surface cold
front will push southeastward through the region. Although some
light shower activity may accompany this front, it will be slowing
down and weakening as it moves through, with a cooler and drier air
mass lagging behind it. Thus, a light northerly wind can be expected
on Sunday morning, but the air mass won`t feel much different as dew
points should remain in the upper 60s to low 70s with morning lows
in the same range. With the front stalled near the coast and no push
of cooler or drier air arriving until Sunday night, pwats around 1.8-
2" and daytime heating should be able to produce weak to moderate
instability, with the front and/or the sea breeze helping to focus
surface convergence near the coast. Although guidance differs in the
coverage of showers and storms, at least isolated activity should
develop during the afternoon, with heavy thunderstorms featuring
gusty winds possible. Some of the high-res guidance suggests a
narrow zone of scattered storms developing just inland of the coast,
where the sea breeze/front ends up drifting due to daytime heating,
but other lower-res guidance tools keep most of the activity
offshore, so PoPs may need to be raised or lowered in future
updates. Daytime highs will depend on the extent of clouds and
timing of any rain, but mid-upper 80s are forecast.
Another shortwave trough pivoting through the Midwest during the day
on Sunday will sharpen up as it crosses through New England during
the night. This will bring a robust push of cooler and drier air
which will shove the cold front offshore, but as the shortwave lifts
away, the front will stall somewhere off the coast by late in the
night. However, cooler and drier air should arrive with dew points
expected to dip into the 50s near and west of I-95 and into the low-
mid 60s east of I-95 to the coast.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
With the stalled front just offshore, an unusual pattern similar to
what was seen in the first two weeks of August will ensue. A robust
high pressure ridge will wedge down the east side of the
Appalachians, resulting in breezy northeast winds, especially as the
pressure gradient tightens between the stalled front and the high.
In addition, extensive cloud cover and occasional rain affecting the
coast appear likely, with rain chances decreasing away from the
coast. Temps will follow a muted diurnal curve amidst this pattern,
with highs in the upper 70s to low 80s and lows in the low-mid 60s.
By Thursday, another mid-level trough may be arriving which
would push the front further away as another cold front dives
southward. However, guidance depictions vary greatly at this far
time range, so this carries very low confidence.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Mostly VFR through the 18Z TAF period. Winds calm by this evening,
and with extra moisture in the atmosphere, confidence is increasing
for fog or perhaps some low stratus before sunrise Saturday morning.
Looks like KILM and KLBT have the greatest chance at recording MVFR
to perhaps IFR restrictions. Fog should mix out by 13-14Z.
Southeasterly winds from the seabreeze kick in again towards the end
of the period.
Extended Outlook...Mostly VFR Saturday afternoon and night, albeit
there could be fog issues again. Rain chances return on Sunday ahead
of a cold front. A wedge of high pressure could bring periodic
restrictions early next week.
&&
.MARINE...
Through Saturday...Southeasterly winds at 5-10 kts become more light
and variable tonight, returning right back to where it was by
Saturday afternoon. Seas hold steady at 1-2 ft.
Saturday night through Tuesday... Generally weak southerly winds (sustained
10 kts or less) early on Saturday night will veer to
southwesterly, then briefly shift to northwesterly as a cold
front pushes into the waters on Sunday morning. However, this
front is expected to stall and drift back to nearshore or
onshore with the sea breeze on Sunday, bringing winds back to
easterly or southeasterly during the day. During Sunday night,
this front will be shoved offshore with north to northeast winds
taking over in its wake. The front will stall over the waters
and result in a tightening pressure gradient as high pressure
builds down from the north, resulting in a period of breezy
northeast winds which may reach SCA criteria from Monday through
Tuesday.
Benign seas around 1-3 ft through Sunday will increase from Sunday
night through Tuesday in tandem with the increasing winds. At this
time, 6+ ft seas are forecast to enter into the coastal water zones
during the afternoon on Monday and peak on Tuesday with heights of 6-
7 ft (possibly up to 8 ft near the 20nmi boundary offshore of Cape
Fear). Given how far out this is, adjustments to timing and peak
winds/wave heights are likely, but a period of SCA conditions is
something to monitor closely for the first half of next week.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Coastal Flood Advisory from 7 PM to 11 PM EDT this evening for
     NCZ107.
SC...None.
MARINE...None.
&&
$$
SYNOPSIS...ILM
NEAR TERM...IGB
SHORT TERM...ABW
LONG TERM...ABW
AVIATION...IGB
MARINE...ABW/IGB

NWS ILM Office Area Forecast Discussion