094
FXUS62 KMHX 281400
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1000 AM EDT Tue May 28 2024

.SYNOPSIS...
A cold front will move through later today. The next front passes
late Wednesday night or early Thursday morning.

&&

.NEAR TERM /Today/...
As of 10 AM Tue...No big changes to fcst as overall theme
remains unchanged. Only updated grids to fine tune areal
coverage and placement of best chances for convection. Inc pops
a bit in favorable sound/sea-breeze induced zones from Mainland
Dare/Hyde County to Downeast Carteret and southern Craven, and
dec a bit closer to the Hwy 17 corridor. Latest HRRR Neural
Network probs are around 20-25% for severe for the coastal
counties, and drop off quickly inland from there.

Prev disc...As of 720 AM Tuesday...

 - Marginally severe seabreeze thunderstorms possible (20-40%
   chance) this afternoon

It appears that a remnant MCV, from convection last night, is
lifting northeast along the coast of the Carolinas at this time.
This feature has been responsible for widespread convection
offshore from Cape Fear to south of Cape Hatteras. Short-term
guidance continues to keep this convection offshore this
morning, and this seems reasonable based on recent radar trends.
Of note, though, any storm splits with sustained left-movers
could send a storm or two towards the coast before the MCV pulls
out to sea. For this reason, I kept a low-end mention of
thunderstorms right along the Crystal Coast/Southern OBX early
this morning. The threat of severe weather this morning appears
low, especially since most of the convection should remain
offshore.

Later today, a cold front will progress southeast across the
Carolinas, eventually moving offshore by this evening. The cold
front passage will be favorably timed with peak diurnal heating
and the development of the afternoon seabreeze. Moisture and
instability are forecast to be lower than yesterday, but heating
of a moist boundary layer (70s dewpoints) should easily support
MLCAPE near 2000 j/kg. Shear will also be lower (around 20-30kt
effective). Short-term guidance varies on the coverage of
storms today, and whether or not the morning convection offshore
will play any role in the afternoon potential. However, I
expect the increased convergence along the front and the pinned
seabreeze will be sufficient to produce at least isolated to
scattered convection in the 12pm-8pm timeframe. The
shear/instability/forcing combination appears favorable for a
marginal risk of severe weather (mainly 40-60 mph wind gusts and
penny to half-dollar size hail). A couple of notables for today
are 1) a slightly drier than normal mid-level airmass, which
could enhance downdraft potential, and 2) if MLCAPE is able to
build to 2000j/kg+, there could be enough support for a short-
lived supercell or two, which would enhance the hail potential.

West of HWY 17, I expect it to stay dry as the front is
forecast to be through there prior to peak heating. Despite the
passage of the front, CAA will be lagging behind, and temps
should still be able to warm above climo for late May.

&&

.SHORT TERM /Tonight/...
As of 230 AM Tuesday...

 - Decreasing thunderstorm risk during the evening

A cold front is forecast to move offshore just after sunset
this evening, with a decreasing risk of thunderstorms after that
time. CAA behind the front isn`t forecast to be overly strong,
but it will feel cooler thanks to lowering dewpoints. Some
guidance is hinting at the potential for fog development behind
the front, perhaps especially where thunderstorms form today.
This seems plausible given a lack of stronger post-frontal
winds. At this time, though, widespread dense fog is not
expected, and ensemble guidance only gives a 10-30% chance of
fog.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
As of 0400 Monday...Mostly quiet long term with dry reinforcing
front clearing Wednesday allowing cool high pressure to build
in late week.

Rest of Workweek...Upper trough persists with shortwaves
passing through the base of the trough Wednesday and again on
Thursday with weak SFC trough developing inland behind the
front. This troughing inland will delay the arrival of the SFC
high from the NW, keeping temps fairly warm Wed. Forecast
remains dry through this period save for Thurs night into Friday
when a shortwave aloft sharpens the upper trough that has been
relatively broad over ECONUS. Temps cool end of the week as the
high pressure begins spilling over the area behind a reinforcing
front pushing the inland troughing offshore. MaxTs in upper
70s, MinTs in the 50s.

Weekend...Upper trough will be offshore as ridging builds over
the area through the entire column with SFC high almost directly
overhead Saturday morning pushing offshore the latter half the
weekend.

Early Next Week...Get back to warm and moist Serly flow regime
with the high pressure now offshore and a developing shortwave
approaching from the W leading to increase in cloudiness and
rain chances.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /through 12z Wednesday/...
As of 720 AM Tuesday...

 - TSRA risk returns this afternoon along the coast

An upper level wave moving off the South Carolina coast at this
time will lift northeast this morning, with SHRA and TSRA
offshore. Some guidance suggests these TSRA may clip the Crystal
Coast early this morning, but even if this occurs, they are
expected to remain south of all of our TAF sites. During the day
today, a cold front will move southeast across the area and
combine with the developing seabreeze, producing SCT TSRA in the
18-00z timeframe. The TSRA risk may reach as far north as KOAJ,
and KEWN. However, with the seabreeze expected to be pinned
closer to the coast, those terminals may end up staying dry. For
this reason, I opted to leave TSRA out of those TAFs for now.
Where TSRA occur, sub-VFR VIS can be expected, in addition to
40kt+ wind gusts and hail. In the wake of the TSRA, low CIGs or
BR/FG may develop, especially where the coverage of TSRA is the
greatest.

LONG TERM /Wednesday through Saturday/...
As of 0400 Tuesday...A drying trend is setting up for the
remainder of the workweek with Thursday night being the
exception.

&&

.MARINE...
SHORT TERM /through tonight/...
As of 720 AM Tuesday...

 - Improving winds and seas

 - Thunderstorm risk this morning through late this evening

Southwesterly winds have laid down some, and are now in the
10-20kt range early this morning. Seas appear to be laying down
now as well, and are in the 3-5 ft range, highest south of Cape
Hatteras. Seas will continue to lay down to 2-4 ft by this
evening. Breezy southwesterly winds will continue through this
evening ahead of a cold front approaching from the NW. That
front is forecast to move southeast across the waters this
evening. Ahead of the front, there will be two opportunities for
thunderstorms. The first will be this morning as an upper level
wave glances the area. This will primarily impact the southern
waters. The second opportunity will be this afternoon through
this evening as thunderstorms develop along the seabreeze, then
shift southeast towards the coast and offshore. While those
should be scattered in nature, the risk could extend as far
north as the northern rivers/sounds/coastal waters.
Thunderstorms through this evening will be capable of 40kt+ wind
gusts and hail.

LONG TERM /Wednesday through Saturday/...
As of 0400 Tuesday...The front finally pushes offshore by early
Wed. Winds briefly turn Nerly behind the front early Wed before
becoming SWerly again as SFC trough/reinforcing front
approaches and moves through Wed night, turning winds Nerly for
the remainder of the work week. Seas generally falling through
the week; 2-4ft Tues, 2-3ft Wed, 1-3ft late week.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...None.

&&

$$
SYNOPSIS...MHX
NEAR TERM...RM/TL
SHORT TERM...RM
LONG TERM...CEB
AVIATION...RM/CEB
MARINE...RM/CEB