386
FXUS62 KMHX 061117
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
717 AM EDT Thu Jun 6 2024

.SYNOPSIS...
High pressure remains off the Southeast coast through today. A
strong cold front will approach from the west Thursday and move
through Friday and Friday evening, with drier conditions this
weekend. Another front will move through Sunday night into early
Monday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 710 AM Thu...Mid-level heights beginning to fall over
eastern North Carolina as a developing wave of low pressure
takes shape over the Ohio Valley ahead of an approaching mid-
level shortwave and attendant elongated upper low over south
central Canada. Attendant cold front is draped roughly from Ohio
southwestward along the western Appalachians, while a pre-
frontal trough is oriented roughly along or just west of the
I-95 corridor. A weak shortwave is currently driving a decaying
area of showers and and occasional thunderstorm off the coast
of SC, but a few odd showers have scraped the Crystal Coast and
this threat will persist for an hour or two more.

Very warm and humid start to the day is expected as temperatures
climb into the 90s and dew points hover around the 70 degree
mark through this afternoon. In addition to driving heat indices
near 100 degrees, instability will markedly increase to an
average of 1500-2000 J/kg SBCAPE (although values of 2500+ are
not out of the question). With heights continuing to gradually
fall with the approaching shortwave trough, airmass will be
increasingly supportive of convective development this
afternoon.

Latest runs of the HRRR are throwing increasingly cold water on
the idea of convection developing along the sea breeze this
afternoon, possibly owing to stabilization thanks to this
morning`s shower activity. Still think there is a primarily
isolated threat of showers and maybe a storm here, and continued
to carry a slight chance PoP for the early afternoon. The
primary focal point of storms will be ahead of the main front
itself, where more organized convective clusters are likely
with better dynamics associated with the shortwave trough. These
storms will approach the coastal plain from the west early this
evening. Outflow boundary interactions between storms will
potentially fuel additional isolated cell development ahead of
this feature. Forecast shear over our area is not expected to
exceed 20 kt, which points to a very low risk of organized
severe storms. Still, with this unstable of an airmass a few
isolated strong cells capable of microbursts are possible.
Torrential rainfall is also a threat given PWATs near 2"
areawide. Given dry antecedent conditions, the risk of flash
flooding is low outside of typically vulnerable (low-lying and
urban) locations.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
As of 405 AM Thu...Cold front will continue to approach the
area overnight. Convective clusters associated with the front
will likely be ongoing although instability will be waning
through the overnight hours. CAMs point to this cluster of
activity pushing off the coast of the Outer Banks overnight.
Once the main cold front begins to cross into the coastal plain
early Friday morning, one last broken band of frontally-forced
showers and a few thunderstorms are likely to develop with CAMS
favoring this activity grazing the Crystal Coast and offshore
locations in the pre-dawn hours. A severe risk is not
anticipated with this activity, although the threat of
torrential rainfall will persist.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
As of 3 AM Thu...The cold front will move through Friday,
finally pushing offshore Friday evening. Mostly dry with a more
comfortable airmass expected this weekend. Another front will
likely push through Sunday night and early Monday, bringing
threat for sct showers and storms.

Friday through Sunday...The front will move through Friday,
finally pushing offshore Friday evening. Isolated showers and
storms may linger along the coast through the day, with
seabreeze likely pinned in the afternoon and weak boundary in
the vicinity. Upper troughing becomes more zonal along the east
coast through the weekend with weak high pressure building in,
keeping area mostly dry. A more comfortable airmass expected
over the weekend with dewpoints falling into the 50s and 60s and
high temps in the 80s Sat and 80s to low 90s Sun.

Sunday night through Wednesday...Still some uncertainty heading
into next week, but starting to come into better focus with much
better agreement in the global guidance. A front will move
through Sunday night into early Monday morning, bringing chances
for sct showers and storms. Upper troughing will continue over
the eastern US, with weak high pressure building in and
potential for weak coastal troughing along the SE coast Mon
through Wed. Will continue with temps and pops near climo
through mid week.

&&

.AVIATION /11Z THURSDAY THROUGH MONDAY/...
SHORT TERM /through tonight/...
As of 715 AM Thu...MVFR cigs overspread a larger area than
anticipated this morning, but with morning sunshine clouds are
already beginning to scatter out and give way to predominant VFR
conditions through the rest of the daytime hours. Exception will
be between 15-18z, when early cu field development could occur
when LCL heights are below 3kft. If any MVFR cigs do develop it
will last no more than a couple hours.

Thinking on convective forecast has evolved since the prior
forecast. Crystal Coast afternoon threat is still present, but
confidence in this scenario has dropped with newest hi-res
guidance now keeping area completely dry until 23-00z. Main
focus remains on clusters of cells developing ahead of the main
cold front, encroaching on the coastal plain early this evening.
Primary threat window is 23-00z to around 04-05z, although a
renewed round of development along the coast overnight will
extend the threat for OAJ until 08-09z. A few stronger storms
cannot be ruled out, especially for any activity north of a line
from HSE- EWN- GWW.

Breezy south to southwesterly winds expected this afternoon with
gusts to 15-20 kt, with a few infrequent gusts to 25 kt possible
across the inner coastal plain.

LONG TERM /Friday through Monday/...
As of 3 AM Thu...Pred VFR conditions expected through Sunday
with weak high pressure building in. Scattered showers and
storms may impact the sites Sunday night into Monday, which may
bring brief periods of sub-VFR.

&&

.MARINE...
SHORT TERM /through tonight/...
As of 410 AM Thu...Deteriorating boating conditions expected
over area waters today ahead of an approaching cold front
currently just west of the Appalachians this morning. Regional
observations show widespread southwesterly winds of 15-20 kts
with the strongest winds over the Pamlico Sound, reaching 20-25
kt at times. Offshore, seas are slowly building to 3-4 feet in
response.

As cold front approaches area waters this afternoon, pressure
gradient will tighten further with more widespread Sw winds of
20-25 kt, particularly for offshore waters and the Pamlico
Sound. Strongest winds are likely after 21z and will begin to
ease after 06z as the front begins to push across the coastal
plain. Seas will continue to build through Fri morning, reaching
up to 6 feet across portions of Raleigh Bay especially beyond
10-15 nm.

SCA headlines were left intact from the previous forecast with
only a few minor adjustments to lengthen expiration times.

LONG TERM /Friday through Monday/...
As of 3 AM Thu...The cold front will move through Friday and
Friday night, with gradient relaxing and winds becoming WSW
10-15 kt. Light to moderate NNW-WNW winds Fri night and Sat
5-15 kt. Moderate to breezy SW flow returns Sunday ahead of
another cold front. SW winds will increase to 15-20 kt by Sunday
evening, with the front moving through Sunday night into early
Monday morning. Seas will subside to 2-4 ft Fri afternoon and
cont through the weekend.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Beach Hazards Statement through this evening for NCZ195-196-
     199-204-205.
MARINE...Small Craft Advisory until 2 AM EDT Friday for AMZ135.
     Small Craft Advisory until 3 AM EDT Friday for AMZ150.
     Small Craft Advisory until 8 AM EDT Friday for AMZ152-154-156-
     158.
     Small Craft Advisory until 6 AM EDT Friday for AMZ231.

&&

$$
SYNOPSIS...MHX
NEAR TERM...MS
SHORT TERM...MS
LONG TERM...CQD
AVIATION...CQD/MS
MARINE...CQD/MS