501
FXUS62 KMHX 010139
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
939 PM EDT Tue Apr 30 2024

.SYNOPSIS...
A weak surface trough will move through the area tomorrow. High
pressure then builds in for a couple of days before yet another
cold front impacts the area over the weekend.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
As of 2140 Tuesday...ISO showers that popped up near the HWY17
corridor as the seabreeze passed has stopped. No more shower
initiation is expected through the first half of the night and
any precip will be from upstream convection that pushes into the
FA. Aside from subtle Td (and therefore RH and AppT grids)
changes, the forecast remains largely unchanged.

Previous Disco as of 350 PM Tue...Upper ridge is beginning to
move offshore this afternoon as a well-defined shortwave over
eastern TN continues to dig towards the Carolinas. At the
surface, high pressure remains anchored south of Bermuda
extending inland, although a weak surface trough associated with
the aforementioned mid-level wave will gradually encroach into
the area through tomorrow.

Hi-res guidance this morning has depicted a slightly more
southern track of the shortwave overnight, with the strongest
attendant lift now across SC and far southeastern NC.
Consequently, CAMs now show the bulk of the heavier
precipitation overnight passing to our south as well and trimmed
back areal coverage of PoPs accordingly. A few more isolated
showers are still possible farther inland. Maintained a mention
of thunder primarily along the coast where instability will
remain highest (up to 500 J/kg). Given a lack of shear (0-6 km
under 15 kt), no severe threat is anticipated. Very mild lows
tonight owing increasing cloud cover and light and steady
southwesterly winds, favoring temperatures in the mid 60s.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
As of 405 PM Tue...Shortwave/low will be overhead and moving
offshore tomorrow morning while surface trough to our west
continues to migrate towards the area. CAMs depict a busy
weather day as convergence with the approaching trough and
diurnal sea breeze aid in convective development early tomorrow
afternoon. Airmass will be sufficiently unstable to support
scattered thunderstorm development (HREF average surface CAPES
reach up to 1000 J/kg, with most aggressive members at 1500
J/kg). The severe threat is low but non-zero, as shear will
initially be weak in the afternoon but begin to increase late as
northwesterly mid-level winds increase on the backside of the
upper trough. If a strong storm were to develop, strong wind
gusts would be the primary threat.

Given a northeasterly mean storm motion, convection is likely
to remain pinned closer to the coast and migrate little inland,
although resultant outflow boundaries will likely spark
additional cells. Some locally heavy rainfall is likely, but
given how dry the past month has been flooding concerns are
minimal. Concentrated the highest PoPs along the Highway 17
corridor. Activity will quickly begin to die off with loss of
heating.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
As of 330 PM Tuesday...

KEY MESSAGES

- Inland highs in the low to mid 80s for the rest of the week

- Best rain chances Wednesday and then an unsettled weekend and
  start to the new week

FORECAST DETAILS

We return to warm, dry weather on Thursday and Friday with a
ridge building over the southeast US. Highs will be in the mid
80s across the coastal plain and low 70s at the beaches.

Unsettled weather returns this weekend with multiple chances for
showers and thunderstorms. Surface high pressure will be
gradually washed out as a surface low forms due to a shortwave
trough moving across the southeast. At the same time, a cold
front associated with a deep low over south-central Canada will
move into our area and stall. PoPs increase west to east on
Saturday with shower and thunderstorm activity possible through
Monday (15-30% chance).

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /through Wednesday Afternoon/...
As of 1900 Tuesday...Carrying a VFR TAF through the period but
conditions will deteriorate Wednesday with subVFR possible. VFR
flight cats prevail across terminals today as high pressure
remains off the southeastern coast and broad diurnal cu field
continues to build inland. Some scattered showers have popped up
as moist SWerly flow skips over the seabreeze as it presses
inland this evening. Have added VCSH for OAJ for the next few
hours. Gusty southwesterly winds will turn southerly late
tonight as sea breeze advances northward. Precipitation forecast
has changed a bit since last night. Guidance has become more
bearish on precip coverage overnight as weak trough of low
pressure approaches from the west. OAJ and to a lesser extent
EWN would be most at risk of seeing overnight shower activity,
as well as an isolated thunderstorm, primarily after 06z.

Isolated to scattered coastal activity will be ongoing after
sunrise on Wednesday, but main focus will turn to the end of the
TAF period as sea breeze converges with trough and brings
scattered to numerous showers and thunderstorms across the area.
Bulk of activity is expected around and after 18z. Have added
VCSH for all terminals in the afternoon and VCTS for coastal
terminals for later in the afternoon. Larger scale conditions
show VFR holding out but subVFR CIGs and/or VIS will be possible
under stronger showers/tstorms, hence the secondary SCT FL030
mention. Potential for fog development overnight WED after rain
has ceased and winds calm which could lead to further flight
restrictions after the end of this TAF period.

LONG TERM /Wednesday night through Saturday/...
As of 330 PM Tuesday...Pred VFR expected through the period but
a few instances of unsettled weather are expected. An
approaching disturbance will bring chances for showers and
thunderstorms on Wednesday (30-60%). By Saturday, a cold front
will be moving into the area and bring another chance for
showers and thunderstorms (15-30%). Lowered CIGs and VIS are
expected during these times.

&&

.MARINE...
SHORT TERM /through Wednesday/...
As of 410 PM Tues...Pleasant boating conditions continue today
as high pressure remains in control, although surface trough
west of the Appalachians will gradually make its way eastward
through tomorrow. Regional observations show seas of 3-4 feet
with periods continuing to increase to 12-13 seconds.
Southwesterly winds hover around 10-15 kt.

Much of the same pattern is expected tonight as the past two,
with winds gradually increasing into the early evening hours
associated with the tightening thermal gradient. A few spotty
gusts to 25 kt are possible primarily across the northern waters
tonight into the overnight hours, but not enough to warrant
headlines. Trough will move into area waters tomorrow with
ambient winds gradually easing through the day, but threat of
showers and a few thunderstorms will increase in the early to
mid-afternoon, especially for the inland rivers and sounds. Seas
remain under 5 feet through the period.

LONG TERM /Wednesday night through Saturday/...
As of 330 PM Tuesday...

KEY MESSAGES

- Sub-SCA conditions with multiple chances for showers and
  thunderstorms

FORECAST DETAILS

Although marine conditions are forecast to remain below SCA
criteria, opportunities for showers and thunderstorms are
possible Wednesday and this weekend. Winds will be variable
through the period due to several systems moving through but
will remain around 5-10 kt with 2-4 ft seas.

&&

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

&&

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