893
FXUS62 KMHX 230730
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
330 AM EDT Mon Sep 23 2024

.SYNOPSIS...
High pressure will remain anchored to the north through mid
week. Next potential frontal system doesn`t near ENC until later
this week.

&&

.NEAR TERM /Through Today/...
As of 330 AM Mon...Upper ridge will shift overhead as high
pressure weakly builds in from the north. This sets the stage
for a seasonable early autumn day across eastern NC with TD`s
in the 60-65 degree range and high temps in the low 80s. Across
OBX and adjacent areas, cool onshore NE flow will keep
temperatures more tempered in the mid to upper 70s. Early
morning stratus will scour out with mo sunny skies expected.

&&

.SHORT TERM /Tonight/...
As of 330 AM Mon...Mainly dry conditions tonight, though some
weakening showers approaching the Coastal Plain counties from
the Piedmont may hold together just enough to wet the ground,
though no more than a hundredth or two of rain is expected.
Otherwise, clouds will steadily increase in coverage overnight
for ENC, limiting the threat for fog potential. Temps will cool
to mainly the mid 60s for most areas, with the coolest readings
nern zones where mo clear skies will hang on the longest.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
As of 200 AM Monday...

 - Above normal temperatures mid-week

 - Watching the tropics late-week

Synoptic Summary: Upper level ridging is forecast to remain in place
across the Southeast U.S. through mid-week, then shift offshore as
an upper level low drops south into the Mid-south. The evolution of
those two upper level features will play a significant role in the
potential tropical system that is forecast to move into the eastern
Gulf of Mexico later this week. Over the weekend, ridging may
attempt to move back over the coastal Southeast U.S.

Tuesday-Wednesday: Low-level thicknesses are forecast to increase
beneath ridging aloft, supporting above normal temperatures,
especially by Wednesday. A few locations may flirt with record warm
lows during this time. For reference, normal highs for late
September are in the low 80s.

Southerly flow beneath the ridge is forecast to support modest low-
mid level moisture advection on Tuesday. At the surface, a weak warm
front is forecast to be draped across parts of NC, and this could be
a focus for isolated to scattered convection. Ridging aloft will
probably be a limiting factor for convective strength and coverage
across ENC, but 30-40kt of deep layer shear in tandem with around
1000j/kg MLCAPE could support a stronger thunderstorm across the
coastal plain. In general, though, the greater coverage of
convection, and better chance of strong thunderstorms looks to
remain to our west. Ridging plus drying aloft should lead to a lower
risk of convection on Wednesday.

Thursday-Saturday: The focus during this period will be the track of
the potential tropical system in the Gulf of Mexico. The recent
suite of 12z/00z guidance has become much more aligned with an
inland track through the Southeast U.S. In general, this puts ENC on
the moist, easterly side of the system, but also removed from the
higher-end wind impacts. This all changes, of course, if the track
shifts east. Of note, with ridging situated just offshore, there may
be a sharp gradient in rainfall on the edge of the system. For now,
the key message with this system is to be aware of the potential,
and to stay tuned to forecast updates through the week.

Sunday-Monday: In the wake of the late-week system, a cold front may
try to slide SW off the Atlantic, and across ENC over the weekend.
While this would tend to bring cooler weather with it, it may also
bring another potential for showers and thunderstorms.

Monday-Tuesday:
High astronomical tides will be impacting OBX beaches Monday-
Tuesday. See TIDES/COASTAL FLOODING section for more
information.

High pressure centered over Maine and the Canadian Maritimes
has a ridge extending south over much of the east coast at the
surface, keeping us dry Monday and Tuesday. Further aloft a high
is centered to our south paired with lows to our west and east
put us in a weak omega block setup allowing the high to linger.
Seasonable temps with highs in the low 80s inland, upper 70s to
near 80 for beaches.

Wednesday-Saturday:
Uncertainty increases a lot towards the middle and end of next
week, as multiple synoptic features will be at play and slight
deviations result in large changes with the forecast. While
ridging continues to spread over ENC from the north Wednesday, a
low pressure system forecasted to be over the Great Lakes will
have a cold front trailing from it extending down to the Gulf
coast. This cold front could stall to our west due to the
ridging over us, or the ridge weakens and gives way to the low,
or the front sweeps north of us around the high. In addition to
the parent low over the Great Lakes and ridge overhead, we will
be keeping an eye on a tropical system that could initiate in
the Gulf Coast within 7 days. It is too soon to determine what
impacts, if any, we receive in ENC should this cyclone form. Due
to all this uncertainty, I opted to keep PoPs at Chc/Schc for
now through the remainder of the long term as a higher moisture
advection regime is more supportive of rain at the end of the
period.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
SHORT TERM /through tonight/...
As of 2 AM Mon...Patchy fog and low stratus becomes more
probable towards daybreak, esp PGV, ISO, and OAJ where tempo
restrictions to IFR cigs are possible after 09Z. Confidence further
east are lower, so EWN is forecast to remain MVFR or higher.
All terminals should return to VFR after 13Z with few to
scattered clouds for the remainder of the day and light erly to
serly winds.

LONG TERM /Tue through Fri/...
As of 200 AM Monday...

 - TSRA possible Tuesday (20-30% chance)

 - Watching the tropics late-week

Isolated to scattered SHRA and TSRA will be possible on Tuesday,
followed by a decreased risk on Wednesday. The chance of SHRA and
TSRA may then increase late week on the outer edges of a potential
tropical system moving inland through the Southeast U.S. Stay tuned
for updates on what impact this system may have to aviation late in
the week.

&&

.MARINE...
SHORT TERM /Through tonight/...
As of 330 AM Mon...Northeasterly winds will be 10-15 kt today
through tonight in wake of backdoor front that crossed the
waters. The bigger concern remains growing swell from a distant
cyclone well offshore, which will result in gradually building
seas from the northeast today through tonight. Seas will be
highest north of Cape Hatteras, peaking at 6-8 feet late
afternoon with a periodicity of around 11 sec. SCA headlines
remain in good shape, leaning heavily on an NBM forecast given
the in- house NWPS model tends to underdo wave heights in long
period northeast flow regimes.

LONG TERM /Tue through Fri/...
As of 200 AM Monday...

 - Elevated seas on Tuesday

 - Renewed risk of elevated winds and seas late-week

 - Watching the tropics late-week

High pressure offshore, plus a weak gradient, is forecast to keep
winds light (5-10kt) through mid-week. Despite the light winds,
northeasterly long-period swell will continue to impact the central
and northern coastal waters with 5-7 ft seas through at least
Tuesday night. After a brief reprieve, another period of elevated
winds and seas appears increasingly likely as a potential tropical
system moves inland through the Southeast U.S. Stay tuned for
updates on this system and what impact it will have on the ENC
waters.

&&

.TIDES/COASTAL FLOODING...
As of 3 AM Mon...No real changes to the forecast thinking as
coastal flooding will continue to be a threat given the higher
than normal astronomical tide cycle today and through Tuesday
afternoon during high tide each day. Coastal Flood Advisories
remain in effect for all oceanside coastal areas into Tuesday
afternoon`s high tide. Increased swell from a low offshore may
bring minor overwash concerns Tuesday and into midweek for the
OBX north of Cape Hatteras, although recent guidance has backed
off some on the strength of this offshore low, which may lessen
the risk of coastal impacts.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Coastal Flood Advisory until 5 PM EDT Tuesday for NCZ195-196-
     199-203>205.
     Beach Hazards Statement from 8 AM EDT this morning through
     this evening for NCZ203-205.
MARINE...Small Craft Advisory until 8 AM EDT Wednesday for AMZ150-152-
     154.

&&

$$
SYNOPSIS...MHX
NEAR TERM...TL
SHORT TERM...TL
LONG TERM...RM/RCF
AVIATION...RM/TL
MARINE...RM/TL
TIDES/COASTAL FLOODING...MHX