156
FXUS62 KILM 211027
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
625 AM EDT Fri Aug 21 2026

.WHAT HAS CHANGED...
Discussions updated. Heat Advisory issued for mainly coastal
counties which may need to be cancelled early depending on the
timing and extent of showers, storms, and associated cloud cover.
Severe thunderstorm risk has increased for inland areas with
isolated damaging wind gusts and hail possible in wet
microbursts. Flash flooding potential remains steady with
isolated instances where storm mergers and multiple storms
tracking over the same area pose the greatest threat for
excessive rainfall in a short amount of time.

&&

.KEY MESSAGES...
1) Heat Advisory for mainly coastal counties with the expectation
for showers, storms, and/or cloud cover to reduce temperatures by
mid-late afternoon.

2) Isolated severe storms and flash flooding possible today through
tonight.

3) Near-normal temperatures expected in the long-term with low rain
chances for Sunday/Monday before increasing midweek.

&&

.DISCUSSION...
KEY MESSAGE 1...Heat Advisory for mainly coastal counties with the
expectation for showers, storms, and/or cloud cover to reduce
temperatures by mid-late afternoon.

Above-normal morning lows and high dew points near the coast will
allow for heat indices to quickly climb this morning. Confidence is
sufficiently high enough to justify a Heat Advisory for mainly
coastal counties. They are the most likely areas to reach heat
indices of 105F or higher for at least two hours around midday to
early afternoon before showers, storms, and/or cloud cover provide
relief from the heat. With deep-layer south to southwesterly flow
through the troposphere, it appears coastal areas may not see precip
until late in the day or overnight as the cold front pushes
closer, thus resulting in the Heat Advisory staying in effect
until 8PM unless it becomes obvious that cloud cover is reducing
heat indices prior to the scheduled end time.

KEY MESSAGE 2...Isolated severe storms and flash flooding possible
today through tonight.

A trough in the jet stream and attendant cold front progressing
eastward into the Carolinas is likely to yield scattered to numerous
showers and thunderstorms today, developing around midday and
continuing through the afternoon into this evening. There is a
slight risk (at least 15% chance) for strong to severe wind gusts
given moderate to strong instability, steep low-level lapse rates,
and anomalously high precipitable water values all contributing to a
wet microburst threat. The strongest storms could also produce hail
up to quarter size, although freezing levels around or above 15kft
will keep this potential limited to the tallest and longest-lived
storms. Bulk shear values generally no greater than 20 kts will
limit storm longevity and intensity, but nearly continuous lightning
and very heavy rainfall will be a hazard in just about any storm.
The severe weather threat is greatest inland of the coastal counties
given the expectation for storm coverage to be highest along and
west of the sea breeze and storm motions to be generally north to
northeastward. Nevertheless, if an outflow boundary from a decaying
storm can push towards the coast and develop new storms, a severe
threat will be present near the coast as well.

In addition, a very moist air mass (precipitable water values of 2-
2.2") combined with fairly slow storm motions (20 kts or less) and
the potential for training storms (multiple storms moving over
the same area) will lead to a slight risk (at least 15%) for
excessive rain leading to flash flooding, mainly near and west
of I-95 and north of US-76. Inland areas will have the highest
coverage of storms as the sea breeze moves inland during the
day, but heavy showers and thunderstorms will remain possible
through much of the night, including at the coast, as the front
draws nearer and upper support comes with it.

KEY MESSAGE 3...Near-normal temperatures expected in the long-term
with low rain chances for Sunday/Monday before increasing midweek.

Scattered showers and thunderstorms will remain possible through
Saturday night as the cold front from Friday stalls just west of or
over the forecast area while impulses aloft continue to move through
the broader trough in the jet stream. A period of mostly dry weather
appears likely on Sunday and Monday as the front is shoved offshore.
However, as the flow aloft becomes westerly to northwesterly around
midweek, additional impulses and waves of low pressure are poised to
bring periods of showers and thunderstorms from Tuesday onward, with
the best chances for more widespread rain currently focused on
Thursday. Of course, given this is multiple days away, the chances
for rain will likely fluctuate in the coming days as smaller-scale
details are worked out.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
Prevailing VFR is expected through most of the period outside of
showers/storms, which have the highest chance of occurrence at KLBT
and KFLO this afternoon. While the actual chances for storms are
higher, PROB30s are currently in place for inland terminals due to
low confidence in when these might occur. Regardless of when these
occur, the duration of impactful restrictions with vis potentially
down to LIFR levels should be short-lived, with MVFR vis in steady
rain possible for an hour or two thereafter as storms congeal and
weaken. A severe wind gust (~50 kts) and hail up to quarter size is
possible in the strongest storms. Showers and storms may develop
near the coast tonight, but confidence is too low to specify a
timeframe as storms during the day near the coast should preclude
additional development overnight. With this issuance also wanted to
start messaging fog development tonight esp inland.

Extended Forecast... MVFR to LIFR restrictions are possible in areas
of ground fog or low stratus tonight into Sunday morning, especially
inland. Scattered thunderstorms may continue through Saturday and
Sunday, mainly near the coast affecting KILM, KCRE, and KMYR.

&&

.MARINE...
Today through Tuesday... Expect generally south to southwest winds
to prevail through the period as an approaching cold front stalls
near the coast. No headlines are expected as winds peak around 15-20
kts over Saturday night and wave heights stay around 3 ft or less
within 20 nmi and up to 4 ft in the 20-60 nmi zones, highest this
weekend.

The biggest marine impact will likely be from increasing coverage of
showers and thunderstorms beginning this evening and continuing
through the weekend as a front stalls near the coast. There will
likely be several rounds of storms, accompanied by reduced
visibility and possible gusty winds.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for NCZ099-105>110.
SC...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for SCZ054>056-058-059.
MARINE...None.

&&

$$

WHAT HAS CHANGED...ABW
KEY MESSAGES...ABW
DISCUSSION...ABW
AVIATION...ABW/MBB
MARINE...ABW