456
FXUS62 KMHX 230718
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
318 AM EDT Sat Aug 23 2025

.SYNOPSIS...
Lingering coastal flooding impacts will continue today,
especially along the Outer Banks. High pressure will move
offshore later today as a weak low moves up the coast and brings
a threat of moderate to heavy rainfall along the coast tonight
through Sunday. A strong cold front will move through early next
week, bringing a noticeably cooler and drier airmass and our
next chance of showers and thunderstorms.

&&

.NEAR TERM /THROUGH TODAY/...
As of 1 AM Saturday...

Key Messages:

- Coastal impacts from Erin will continue through today, especially
along the Outer Banks

- Increasing PoPs from south to north later this afternoon/evening

Weak high pressure over the area will move east and off the mid-
Atlantic coast later today. To our south, a weak boundary
associated with a surface low currently sitting over the FL/GA
border will gradually lift north. This will increase our cloud
cover from north to south through the day with slight chance
PoPs bleeding into our southern zones by late afternoon/early
evening and continuing to increase thereafter. PWATs will
increase to 1.5-2.5" ahead of the boundary, which may support a
few scattered moderate to heavy showers before sunset, but the
heavier and more widespread activity looks to kick off after
dark.

Temperatures and humidity will feel similar to yesterday with highs
in the low- to mid-80s.

Although the remnants of Erin will get progressively farther
away from our coast today, coastal flooding impacts are
expected to continue due to elevated water levels from large
swells, higher than normal astronomical tides, and compromised
dune structures. Continued coastal impacts are expected farther
south as well (see the TIDES/COASTAL FLOOD section for details).

&&

.SHORT TERM /TONIGHT/...
As of 2 AM Saturday...

- Heavy rain is possible late tonight, generally east of Highway 17

- Heavy rain may exacerbate ongoing coastal flooding to portions
  of the Outer Banks

Chances for showers and thunderstorms will continue to increase from
south to north overnight as the aforementioned weak surface low
moves up the coast. Areas generally east of Highway 17 and
along/south of Highway 264, especially along the coast and offshore,
will have the best chance at seeing moderate to heavy rainfall and a
few rumbles of thunder. Depending on where exactly this low tracks
will further hone the QPF, but as of now, 1-2" of rain can be
expected in this area with 0.5-1" or less elsewhere. Slow
southeasterly storm motions will be roughly parallel to the
boundary, which will support the potential for training cells.
With this in mind, a reasonable worst case scenario would be
2-4" with locally higher amounts of 5"+.

Lows will reach the upper-60s to low-70s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
As of 245 AM Saturday...

Key Messages

 - Monitoring heavy rain/flooding potential along the coast Sunday

 - Below to well below normal temperatures mid-week

A notable area of low pressure is forecast to lift NE along, or just
off, the coast of ENC on Sunday. Most ensemble guidance suggest the
low may get as deep as 1005-1010mb. While not significantly deep,
the low should provide an area of enhanced low level convergence in
tandem with a stationary baroclinic zone that is forecast to reside
in the vicinity of the central/southern OBX. Additionally, large-
scale forcing may get a modest boost from the entrance region of an
upper jet that will be translating east across the Mid-Atlantic. The
area of enhanced lift will overlap with modest instability and PWATs
of around 2", supporting showers and thunderstorms with higher
rainfall rates.

The biggest forecast challenge with this low is what track it will
take as it lifts NE, and how far west/inland the above-mentioned
baroclinic zone will get. If the low stays offshore, the heaviest
rainfall will likely follow suite. However, a track along, or just
inland of, the coast should help to encourage the baroclinic zone to
at least reach the coast, setting up the potential for a zone of
heavy rainfall rates, especially as showers and thunderstorms will
have a tendency to train along the baroclinic zone. In general, an
area of 1-2" of rain appears likely along the coast. However, if the
baroclinic zone manages to reach the coast, the reasonable worst
case scenario guidance suggests amounts as high as 3-6" would be
possible. The OBX have been fairly dry over the past couple of
weeks, and normally this wouldn`t immediately trigger alarm bells.
However, oceanside and soundside water levels remain elevated in the
wake of Erin, which has continued to support coastal flooding
impacts. Heavy rain on top of those elevated water levels may
enhance flooding impacts over a relatively small area of the OBX,
specifically portions of Hatteras and Ocracoke Islands where some of
the worst impacts of Erin occurred. A Flood Watch was contemplated
for this area, but this could be confusing in light of the ongoing
Coastal Flood Advisories. To help simplify the hazards, the heavy
rain on top of coastal flooding will be addressed in the coastal
flood advisories. For the rest of the OBX and the Crystal Coast,
heavy rain and minor flooding will be possible, but the potential
impacts do not appear to warrant a Flood Watch at this time. Stay
tuned in case this changes. For additional information, please see
the Tides and Coastal Flooding section of the AFD below.

After this weekend, attention turns to a strong cold front which is
forecast to move through late Monday or Monday evening. Scattered
showers and thunderstorms may accompany this front. In fact, modest
shear of 20-30kt overlapping weak instability (MLCAPE of 500-
1000j/kg) may allow a strong thunderstorm, or two, to develop.
However, the risk of severe thunderstorms appears low due to a lack
of better lift and moisture.

This cold front will usher in a noticeably cooler airmass by mid-
week, with temperatures expected to be a solid 5-10 degrees below
normal. This will especially be noticeable at night as lows drop
into the 50s and 60s. The lowest temperatures are expected Wednesday
night, and it`s within the realm of possibility that a few record
lows could be in jeopardy for the typically colder inland locations.

Late in the week, guidance begins to significantly differ. Within
broad troughing across the ERN U.S., the potential exists for
another coastal low to develop near the coast of the Carolinas.
Should this occur, we could be looking at another round of heavy
rain and gusty winds for portions of the area.

&&

.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /through Saturday/...
As of 1:30 AM Saturday...VFR flight conditions are expected
through the period. Scattered high clouds early this morning
will become broken by early afternoon as moisture increases
ahead of a weak low moving up the coast. Chances for showers and
thunderstorms will increase from south to north starting later
this afternoon and continuing into the overnight hours. The
atmospheric setup will support moderate to heavy rainfall with
the potential for training cells, especially along the coast.
OAJ and EWN will have the greatest chances at seeing decreases
in VIS and CIGs from this heavier rainfall later tonight.

LONG TERM /Sat night through Wed/...
As of 245 AM Saturday...

A surface low will lift northeast along the coast Sunday, leading to
an increased risk of sub VFR conditions in low clouds and SHRA. TSRA
will be possible as well, mainly along the immediate coastline. A
cold front then moves through late Monday or Monday evening with a
northwesterly wind shift and a risk of SCT SHRA and TSRA. Much drier
air moves in behind this front, with VFR conditions returning.

&&

.MARINE...
SHORT TERM /through Saturday/...
As of 245 AM Saturday...

Northeasterly winds of 5-15kt will become east, then southeast,
later today and especially tonight as an area of low pressure
develops off the coast of SC. As this low approaches the ENC waters,
there should be an increased risk of showers and thunderstorms,
especially south of Cape Hatteras. Seas of 4-8ft at 10-13s are
expected to continue through tonight.

LONG TERM /Sat night through Wednesday/...
As of 245 AM Saturday...

A modestly deep area of low pressure is forecast to lift northeast
through the ENC coastal waters tonight-Sunday. While notably deep,
the risk of 25kt winds appears low (<10% chance). However, the low
will bring an increased risk of thunderstorms on Sunday, especially
for the coastal waters south of Oregon Inlet. Areas of enhanced
winds may accompany the thunderstorms, along with a risk of
waterspouts. Meanwhile, northeasterly long-period swell emanating
from the remnants of Erin will continue to impact the coastal
waters, especially north of Ocracoke Inlet. Additionally, Sunday`s
low may help to enhance the swell, adding a modest wind swell on top
of the long-period swell. This is expected to keep seas elevated
through the weekend (4-8ft at 10-12s). Because of this, Small Craft
Advisories will remain in effect through the weekend, with the
potential for elevated seas to last into early next week. After this
weekend, a strong cold front will move through late Monday or Monday
evening. Winds will briefly flip back to southwesterly ahead of the
front, then become northwesterly behind it.

&&

.TIDES/COASTAL FLOODING...
As of 245 AM Saturday...

Coastal flooding impacts are expected to linger across portions of
the OBX over the next 24-36 hours as water levels remain elevated,
both due to lingering long period swell and an astronomically higher
tide cycle. Because of this, a Coastal Flood Advisory remains in
effect where the impact is expected to be the greatest. For the
Crystal Coast, the Coastal Flood Advisories have been cancelled as
overall water levels should subside enough to keep impacts more
limited. That said, inundation of up to 1 ft AGL may last through
one more high tide cycle today.

Of note, an area of low pressure is forecast to lift northeast along
the coast later tonight through Sunday. While strong winds are
currently not expected with this low, there may be enough of an
enhancement to the onshore flow north of Cape Hatteras to add to the
ongoing coastal flood impacts. Additionally, a period of very heavy
rain may accompany this low, and the potential exists for rainfall
amounts as high as 2-4" to occur over Hatteras and Ocracoke Islands.
The heavy rain on top of elevated water levels with ongoing coastal
flooding may locally enhance flooding impacts. This heavy rain may
also hamper ongoing cleanup and restoration efforts along the OBX.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Beach Hazards Statement from 7 AM EDT this morning through
     this evening for NCZ196-203>205.
     Coastal Flood Advisory until midnight EDT tonight for
     NCZ203>205.
     High Surf Advisory until midnight EDT tonight for NCZ203-205.
MARINE...Small Craft Advisory until 2 PM EDT Sunday for AMZ150.
     Small Craft Advisory until noon EDT Tuesday for AMZ152-154.
     Small Craft Advisory until midnight EDT Sunday night for
     AMZ156-158.

&&

$$

SYNOPSIS...MHX
NEAR TERM...OJC
SHORT TERM...OJC
LONG TERM...RM
AVIATION...RM/OJC
MARINE...RM
TIDES/COASTAL FLOODING...MHX