997
FXUS62 KILM 200602
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
202 AM EDT Wed Aug 20 2025

.SYNOPSIS...
Hurricane Erin is expected to remain far enough offshore to
keep substantial wind and rain impacts away, but will still bring
dangerous surf to the beaches for much of the work week. With a
stalled front south of the area, rain chances are expected to
remain confined primarily in southwestern portions of the
forecast area until late in the weekend, when another cold
front is expected to sweep through. This front should bring
cooler and drier air in its wake early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Moisture gradients depict a weak cold front stalled just west of the
I-95 corridor. Low clouds will disproportionately favor the cooler
side of the boundary this morning with better mixing and
inconsistent cloud cover allowing for peeks of sunshine to develop
east of the front by mid or late morning (possibly earlier).

Water vapor imagery indicates that Erin is pulling dry air around
its northwestern periphery and into our forecast area. With drier
air dominating the mid and upper levels, large scale subsidence
around the storm should also limit forcing this afternoon. These two
factors generally lean toward a dry forecast for much of the area
today. Despite most areas staying dry, onshore moisture advection
will interact with mesoscale convergence near the coast. Along this
near-surface moisture gradient, shallow showers should win-out
against the negative synoptic influences. Entraining dry air could
allow a few of these showers to pack some locally strong, non-
severe, wind gusts.

Gradient winds will increase today as the pressure gradient
associated with Erin tightens across the area. Most of us should see
sustained winds around 10-15 mph inland and 15-20 mph along the
coast. Coastal areas will see afternoon gusts up to 25 mph with
inland areas up to 20 mph. Inland areas should decouple well with
mostly clear skies early, but coastal areas will maintain similar
winds (slightly weaker gusts) through Thursday morning.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Erin should be just past the latitude of Wilmington by sunrise
Thursday and accelerating away to the northeast, with breezy north-
northwesterly winds weakening late in the day. Precip should stay
offshore and high clouds spreading out from the hurricane will pull
away to the northeast through the day. Dry air and subsidence aloft
behind Erin should keep the daytime dry with highs in the upper 80s
to low 90s.

Overnight, some mid-level shortwave energy from the trough which
kicks Erin away is expected to slide into the Southeast US,
interacting with a stalled front delineating considerably drier air
over the forecast area from much more humid air to the south. Where
this front is located will help determine the extent of precip
development, but it appears much of the forecast area will remain
dry with a northeast wind dominating. There is a low chance that the
southern and western tier of counties in NE SC (mainly from
Darlington through Georgetown) could see some showers develop amidst
somewhat greater moisture nearer to the front, but PoPs are
generally 30% or less at this point. With drier air seeping into the
northern counties, overnight lows should dip into the upper 60s to
low 70s in the Cape Fear area and lower 70s in NE SC.

On Friday, the position of the front will help determine how far
north precip ends up reaching, but current guidance suggests the far
southern counties have the best chance of seeing any showers and
perhaps a thunderstorm on the northern periphery of the high pwat
airmass while the vast majority of the forecast area remains dry
otherwise. Highs should reach the middle 80s as remnant troughing
keeps height lower than usual behind Erin and surface high pressure
keeps a northeast wind in place, which veers to easterly in the
afternoon.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As mid-level ridging shifts across the area, surface high pressure
will remain north of the region and maintain easterly winds through
at least Saturday. Beyond then, a significant closed low and
attendant trough will shift out of central Canada and help to push
the surface high eastward and bring the stalled front back towards
the area, with a surface low potentially developing along the front
as well. Whether this front draws close enough to the coast to bring
a focused heavy storm threat remains to be seen, but increasing
moisture should lead to isolated to scattered activity on Sunday. In
addition, a cold front pushing southeastward ahead of the trough may
also lead to a focused band of showers and storms if it comes
through during the afternoon or evening. Current guidance tools
suggest an overnight or Monday morning passage with a decaying band
of showers surviving, but at this juncture, the timing is subject to
change. Regardless of when the frontal passage occurs, a
refreshingly cool and dry air mass would follow as high pressure
coming out of central Canada spreads southeastward behind the front.

Temperatures are expected to remain fairly steady through the period
with highs generally in the middle 80s and lows in the upper 60s to
lower 70s.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Onshore moisture advection and northeast flow should produce low
stratus this morning across both inland and coastal terminals.
Confidence is low given the increased boundary layer winds and weak
pressure fields creating the wedge. However, an inversion around 1k
ft AGL should trap any near-surface moisture. Current thinking is
that MVFR will develop along the coast with IFR quickly
transitioning to MVFR inland. Cloud cover should not be as stubborn
today given that the front has pushed inland toward the I-95
corridor.

Convergence along the coast this afternoon and interaction with a
staggered sea breeze should produce a few isolated showers or
storms. Current thinking is that all coastal terminals have a chance
of seeing a shower, but best chance would be ILM. Winds increase
this afternoon as the gradient from Erin builds northward. Expect
gusts up to 20 knots this afternoon inland, up to 25 knots near the
coast.

Extended Outlook... Gusty winds continue into Thursday with Erin
well offshore of the NC coast. Gradual improvement is expected late
Thursday into Friday before a cold front approaches the area by the
weekend. Cooler temperatures and increased rain chances are possible
through the weekend.

&&

.MARINE...
Through Tonight... Winds increase today as the pressure gradient
associated with Erin tightens across the area. Winds up to 20-25
knots will primarily impact the NC coastal waters with periodic,
infrequent, gusts up to 35 knots possible through tonight. Rough
seas peak later today and tonight with long-period swell and NE wind
waves. Dangerous navigation conditions are likely to begin gradual
improvements by Thursday morning.

Thursday through Sunday... Hurricane Erin will influence the winds
through Thursday night with breezy north-northwesterly winds
gradually subsiding through the night. SCA-level winds are expected
through Thursday morning, mainly near and north of Cape Fear, as
Erin makes her closest approach and pulls away. Wave heights are
expected to decline fairly rapidly through Thursday night with
initial heights around 8-12 ft north of Cape Fear in the early
morning subsiding to below 6 ft by late Thursday night. Wave heights
south of Cape Fear in the 5-10 ft range early on Thursday are
expected to decrease to 2-4 ft by late Thursday night. The primary
east-southeasterly swells related to Erin with a period of around 15-
16 seconds will be replaced by east-northeasterly swells with a
period around 13-14 sec as she pulls away. Northwesterly wind waves
develop on Thursday with heights around 2-4 ft through the daytime
hours before subsiding overnight.

&&

.TIDES/COASTAL FLOODING...
Minor coastal flooding is expected along the Lower Cape Fear
River during the late afternoon and evening high tide cycles
into late week, basically within a 3 hour window centered on
high tide. May also see minor coastal flooding during the
morning high tides. Minor coastal flooding is also expected
along the SE NC and NE SC coasts into late week, mainly during
the evening high tides.

Runup from large waves associated with Hurricane Erin could also
result in some beach erosion and ocean overwash in vulnerable
coastal locations such as those without protective dunes.

RIP CURRENTS: A high risk of rip currents is expected through
Friday as large swells from Hurricane Erin impact the coast.

HIGH SURF: A High Surf Advisory is in effect for dangerously
rough surf with 6+ foot breaking wave heights for much of the
SE NC and NE SC coasts, especially east to southeast-facing
beaches.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...High Risk for Rip Currents through late tonight for NCZ106-108-110.
     High Surf Advisory until 11 PM EDT Thursday for NCZ106-108-110.
     Coastal Flood Advisory from 4 PM this afternoon to 8 PM EDT
     this evening for NCZ106-108-110.
     Coastal Flood Advisory from 6 PM to 11 PM EDT this evening for
     NCZ107.
SC...High Risk for Rip Currents through late tonight for SCZ054-056.
     High Surf Advisory until 11 PM EDT Thursday for SCZ054-056.
     Coastal Flood Advisory from 4 PM this afternoon to 8 PM EDT
     this evening for SCZ054-056.
MARINE...Small Craft Advisory until 8 PM EDT Thursday for AMZ250-252.
     Small Craft Advisory until 5 PM EDT Thursday for AMZ254-256.

&&

$$

SYNOPSIS...ILM
NEAR TERM...21
SHORT TERM...ABW
LONG TERM...ABW
AVIATION...21
MARINE...21/ABW
TIDES/COASTAL FLOODING...ILM