411
FXUS62 KMHX 240723
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
323 AM EDT Sun Aug 24 2025

.SYNOPSIS...
A coastal low will bring moderate to heavy rainfall along the
coast today. A strong cold front will move through late Monday,
bringing a noticeably cooler and drier airmass and our next
chance of showers and thunderstorms.

&&

.NEAR TERM /THROUGH TODAY/...
As of 2 AM Sunday...

Key Messages:

- Heavy rainfall and flash flooding concerns along the coast today

Latest surface observations show a coastal low moving north just
east of the GA/SC border. Scattered showers are moving across the
area this morning as this feature draws closer, and coverage and
intensity will increase over the next few hours. There will likely
be a sharp precip gradient roughly along Highway 17 today with
the axis of greatest precip being along the coast and Outer
Banks. QPF has increased to 2-4" along the coast, 4-6" along the
central Outer Banks, and an inch or less elsewhere. It should
be noted that the latest HREF LPMM shows areas of 7-10" near the
coast, which isn`t out of the realm of possibility if training
cells were to occur. A Flood Watch remains in effect for Coastal
Onslow, Carteret, southern Craven, Hyde, and Dare counties. See
the HYDROLOGY section for more details.

&&

.SHORT TERM /TONIGHT/...
As of 2:30 AM Sunday...The coastal low will progress north and away
from our CWA. Showers may linger near/along the Outer Banks early
tonight, but the coastal plain should remain dry. With decreasing
cloud cover and decoupling winds across the coastal plain, this will
set the stage for fog. Clouds will hang on longer along the coast,
so confidence for fog to develop in these areas is lower. Temps will
bottom out in the upper-60s to low-70s.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
As of 245 AM Sunday...

Key Messages

 - Below to well below normal temperatures mid to late-week

A cold front is forecast to move through ENC Monday afternoon or
early evening, eventually ushering in a noticeably cooler airmass.
Prior to that, a brief period of southerly flow ahead of the front
should allow temps to warm into the mid to upper 80s, which is right
around normal for late August. Limited moisture advection is
expected ahead of the front thanks to the short residence time of
southerly flow in the wake of today`s coastal low. In general, this
is expected to limit the coverage and strength of any thunderstorms
that manage to develop, despite improved forcing.

Behind Monday`s front, an anomalously deep upper trough will move
over the ERN U.S. Within this trough, a fast-moving mid-level
shortwave is forecast to pivot through the Southeast U.S. Tuesday
night into Wednesday, with an area of low-mid level frontogenesis
overlapping with modest moisture. This may allow a quick round of
showers Tuesday night-Wednesday morning. In the wake of that wave,
strong high pressure is forecast to settle into the region, along
with a much drier airmass. This should do two things - 1) support a
decreased chance of showers and 2) support a period of below to well
below normal temperatures.

During this time, the ECMWF`s EFI suggests the potential for record
or near-record low temperatures. For reference, normal highs this
time of year are in the upper 80s, and normal lows are in the low
70s. The latest blended guidance suggests lows in the 50s inland and
60s along the coast, with the potential for highs to only top out in
the 70s to low 80s. Of note, some of the coolest available guidance
suggests lows in the mid 50s inland, and low to mid 60s along the
coast. It appears that the coolest night will be Wednesday night as
high pressure moves overhead, allowing the best radiational cooling
conditions.

Later in the week, deterministic guidance have begun to back off on
the potential for another coastal low to develop near the Southeast
U.S., although there is still a modest signal in ensemble guidance.
We`ll continue to monitor this potential, but given the recent
trends, the late-week period is beginning to look drier and
potentially cooler.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /through Sunday/...
As of 2:45 AM Sunday...VFR flight cats are holding strong this
morning but with a coastal low approaching from the south and
scattered showers becoming more widespread, the expectation is for
CIGs and VIS to drop to MVFR from south to north over the next
couple of hours. There will likely be a sharp precip gradient
roughly along Highway 17 today with the axis of greatest precip
being along the coast and Outer Banks. Flying conditions will be
most impacted between 11-18Z, especially for EWN and OAJ, where CIGs
are forecast to drop to IFR around sunrise with reductions in VIS as
well because of heavy rainfall. This evening, PoPs will decrease
from west to east, skies will clear, and winds will decouple. The
coastal plain will provide the best environment for fog to develop
early Monday morning as slightly greater cloud cover will linger to
the east.

LONG TERM /Sunday night through Thursday/...
As of 245 AM Sunday...

A cold front will move through Monday afternoon and evening, and may
be accompanied by a low-end chance of SHRA and TSRA (20-30% chance).
Another chance of SHRA is expected Tuesday night into Wednesday
morning, although the chance of TSRA appears low (<10% chance). Sub-
VFR conditions may accompany Monday`s SHRA and TSRA, but then an
extended period of mostly VFR conditions is anticipated. The one
exception is during the overnight and early morning hours mid-week
as there is a good signal for radiational cooling BR/FG development.

&&

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

Key Messages

 - Coastal low to bring elevated winds and seas and an increased
risk of thunderstorms through this afternoon

- Lingering long period swell to keep seas elevated into Monday

A disorganized, but modestly deep, area of low pressure is forecast
to lift northeast along the coast of NC over the next 12-18 hours,
pulling away from the area by tonight. Buoys to the south of the
area have shown easterly winds of around 15kt, with gusts as high as
20-25kt. Given the disorganized nature of the low, it`s unclear
where the strongest winds will be focused. If a more consolidated,
and deeper, area of low pressure develops (as some guidance
suggests), then there would be an increased risk of 25kt winds and 5-
6ft seas. Regardless, an increased risk of thunderstorms is
anticipated through this afternoon, especially across the coastal
waters south of Oregon Inlet. The strongest thunderstorms will be
capable of winds in excess of 30kt and waterspouts.

Meanwhile, lingering long period ENE swell (5-7ft at 11-13s) will
continue to impact the coastal waters north of Cape Lookout through
tonight. A Small Craft Advisory remains in effect for those waters.
An expansion of the SCA was considered for the coastal waters south
of Cape Lookout (mainly for today`s coastal low), but for now it
appears the impacts will be relegated to a small area of those
waters, and I opted to hold off for now.

LONG TERM /Sun night through Thursday/...
As of 245 AM Sunday...

An extended period of northeasterly flow (10-15kt) is expected over
the upcoming week. The exception is Monday as the flow briefly
becomes southerly ahead of a cold front which is slated to move
through Monday evening. Long period ENE swell from the remnants of
Hurricane Erin will continue to gradually lay down, with seas
expected to finally fall below 6ft by Tuesday. Seas of 2-4 ft are
then expected to be the theme for the rest of the week. Of note,
some ensemble guidance continue to suggest another coastal low may
develop east of the Carolinas mid to late week, although this signal
has trended weaker. Should a low develop, there could be a bump up
in winds and seas.

&&

.HYDROLOGY...
As of 3 AM Sunday...A coastal low will move up our coast today
and bring a threat for heavy rainfall and flooding along the
coast and Outer Banks. PWATs will ramp up to 2.5"+ ahead of and
with the low, and when paired with ample surface forcing and
long skinny CAPE profiles, torrential downpours are likely. The
mean cloud layer wind and corfidi upshear vectors support
progressive storms, but with the mean wind parallel to the the
axis of rainfall, training cells are expected. A swath of 2-4"
is expected east of Highway 17 with 4-6" along the central Outer
Banks and locally higher amounts of 7"+. A Flood Watch remains
in effect for Coastal Onslow, Carteret, southern Craven, Hyde,
and Dare counties.

Areas along the Outer Banks impacted by coastal flooding and
storm surge from Erin may be more susceptible to flash flooding
than normal, especially during high tide cycles in areas with
compromised dune structures.

&&

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

Coastal gauges across the area suggest water levels are finally on
the downward trend in the wake of Erin. Because of this, all Coastal
Flood Advisories have been cancelled. Astronomically higher tides
are also coming down, but some very minor inundation up to 1 ft
appears possible for at least one more day. Along the OBX, lingering
long period swell may continue to produce some impacts at high tide,
especially for areas where dunes have been damaged. In light of
this, a High Surf Advisory will remain in effect through this
morning`s high tide. We`ll continue to assess conditions to see if
any extension in time is needed.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Flood Watch through this afternoon for NCZ047-081-203>205.
     Flood Watch until 11 AM EDT this morning for NCZ094-194>196-
     199.
     Beach Hazards Statement through this evening for NCZ196-
     203>205.
     High Surf Advisory until noon EDT today for NCZ203-205.
MARINE...Small Craft Advisory until 8 PM EDT this evening for AMZ150.
     Small Craft Advisory until 8 PM EDT Monday for AMZ152-154.
     Small Craft Advisory until midnight EDT tonight for AMZ156.

&&

$$

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