339
FXUS62 KMHX 141339
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
939 AM EDT Tue May 14 2024

.SYNOPSIS...
A low pressure system will bring unsettled weather across the
area today into tomorrow. High pressure builds in late Thursday
before another low pressure system impacts us this weekend.

&&

.NEAR TERM /TODAY/...
As of 940 AM Tue...No significant changes needed to previous
forecast for late am update.

Mid-level ridge axis has crested over the Carolinas this
morning, allowing heights to fall as a central plains closed low
and associated shortwave trough digging into the lower MS
Valley shift eastward. At the surface, high pressure centered a
few hundred miles offshore is gradually weakening while complex
low pressure migrates along a stalled frontal boundary draped
along the Gulf Coast.

Increasingly inclement weather is expected today as the mid-
level trough and associated surface low lift towards our area
over the next 24 hours. Light isentropically driven showers are
increasing in coverage across the Carolinas and Virginia this
morning and will continue to do so through the AM hours from
west to east. QPF amounts will amount to a tenth of an inch or
less.

The most impactful rainfall will lift across the region later
this afternoon as the aforementioned frontal boundary to our
south lifts north with a wave of low pressure migrating along
it. The combination of strong frontogenetic forcing and upper
level support with an approaching vort max strongly suggest
numerous to widespread coverage of showers, and raised PoPs to
100% for most of the area. Of additional concern is the risk of
very heavy rainfall, given very saturated model soundings and
forecast PWATs soaring north of 1.75". For climatological
context, the 90th percentile of PWATs for today is around 1.50".
Daytime rainfall totals will approach an inch along and west of
Highway 17.

Persistent cloud cover and rain will keep the diurnal curve
today relatively flat, but it will still be warm and muggy with
highs in the low 70s and dew points pushing into the mid to
upper 60s especially along the coast.

&&

.SHORT TERM /TONIGHT/...
As of 430 AM Tue...Once the warm front crosses the region in
the evening, instability will quickly increase behind it and a
few thunderstorms are possible. Given long skinny CAPE profiles,
these storms could result in isolated but strong downpours and
pose a risk for flooding particularly in urban and poor drainage
areas, despite dry antecedent conditions. HREF guidance, as
well as NBM probabilistic output, point to a low (10%) risk of
storm total rainfall amounts pushing up to 3" wherever these
cells may track. Heavier band of rainfall will lift across the
Outer Banks through midnight.

A brief lull in precipitation is likely after midnight as dry
slot moves overhead, but a few stray showers and thunderstorms
are still possible and kept PoPs at chance for the period. Very
mild temperatures overnight, falling into the mid to upper 60s.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
As of 515 AM Tuesday...Unsettled weather will impact ENC on
Tue/Wed as a deepening low pressure tracks across the Southeast
and Mid-Atlantic. High pressure builds in Thursday night into
Friday but another low pressure system will impact the area late
in the week.

Wednesday through Wednesday night...Additional showers will
push across the area Wednesday as the upper level trough and
attendant sfc cold front pushes across the area. A better
chance for stronger storms with better upper level support,
colder temps aloft, and greater instability coupled with around
30-40 kt of bulk shear. SPC has a marginal risk (1 of 5) of
severe storms across the coastal plain on Wednesday. Temps will
continue to be seasonable with highs in the low to mid 80s

Thursday through Monday...Upper ridging builds in from the west
Thursday with a vertically stacked low off the Mid-Atlantic
coast slowly moving eastward. ECWMF continues to be the slowest
solution keeping cyclonic flow across the area keeping isolated
showers and thunderstorm chances through much of the day and
will keep slight chance PoPs. Ridging crests over the area
Thursday night but will slide offshore Friday with another
frontal system quickly moving into the area late in the week but
once again guidance differs with how the system evolves as it
pushes across the Southeast and off the coast over the weekend.
But despite the differences, most guidance brings another round
of descent rainfall amounts across much of the area.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /through 12z Wed/...
As of 720 AM Tue...There is a high chance (>95%) of sub- VFR
flight conditions over the next 24 hours with a high chance
(70%) of IFR or worse.

VFR conditions continue to hold strong this morning, but
conditions upstream are quickly deteriorating and will continue
to do so as a complex area of low pressure currently draped
along the Gulf Coast lifts towards the Carolinas tonight.
Isentropically driven showers will further expand across the
area today, and MVFR conditions will accompany this activity.
The heaviest rainfall will most likely occur after 18z as
strongest lift, juxtaposed with deepest moisture, pivots across
ENC from the southwest. Predominantly IFR conditions are likely
with this heavier activity and will linger through the remainder
of the period. Thunderstorm chances increase for all terminals
after 00z tonight, although the best chances are most likely for
OAJ and EWN.

Southeasterly winds gust this afternoon to 15-20 kt, then calm
and veer south to southwesterly as surface low lifts across NC
late tonight.

LONG TERM /Wednesday through Saturday/...
As of 5 AM Tuesday...A low pressure system will impact the area
through Wednesday with periods of sub- VFR continuing into
Wednesday. Sub-VFR conditions possible Wednesday night with
plenty of low level moisture in place. Pred VFR returns Thursday
but could see isolated showers bringing brief sub-VFR
conditions. Pred VFR continues Friday but another frontal system
will approach the area bringing increasing clouds with sub-VFR
possible Friday night into Saturday.

&&

.MARINE...
SHORT TERM /through tonight/...
As of 940 AM Tue...Increasingly inclement boating conditions
expected over the waters today as complex area of low pressure
currently over the Gulf Coast lifts towards the Carolinas.
Latest obs show S-SE winds 10-20 kt, with seas 2-4 ft north of
Hatteras and 3-6 ft south. Winds will gradually increase through
today as pressure gradient is pinched, with a surge to 20-25 kt
migrating across the waters from south to north through
tonight. Offshore, seas will quickly build in response reaching
6-8 feet particularly across Onslow and Raleigh Bays.

As low and attendant warm front cross the waters tonight, winds
will veer southwesterly and decrease to around 10-15 kt. Still,
seas will be slow to respond and remain above 6 feet through the
end of the period. Inherited SCA headlines look excellent and
were retained apart from a modest timing change for the waters
north of Oregon Inlet.

LONG TERM /Wednesday through Saturday/...
As of 515 AM Tuesday...Low pressure will pull away from the
waters on Wednesday while a cold front pushes through Wednesday
night and Thursday. SW winds around 15 kt Wednesday becomes Nly
Wednesday night behind the cold front. Small Craft Advisory
conditions continue with seas around 5-7 ft early Wednesday,
gradually subsiding to below 6 ft late Wednesday/Wednesday
night. High pressure build into the area Thursday night bringing
light winds then slides offshore Friday with winds becoming Sly
around 10-15 kt Friday night and Saturday ahead of the next
frontal system with seas around 3-5 ft.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Beach Hazards Statement until 8 PM EDT this evening for NCZ195-
     196-199-204-205.
MARINE...Small Craft Advisory from 6 PM this evening to 4 AM EDT
     Wednesday for AMZ131-230-231.
     Small Craft Advisory from 3 PM this afternoon to 4 AM EDT
     Wednesday for AMZ135.
     Small Craft Advisory from 3 PM this afternoon to 2 AM EDT
     Wednesday for AMZ136-137.
     Small Craft Advisory from 8 PM this evening to 6 PM EDT
     Wednesday for AMZ150.
     Small Craft Advisory from 3 PM this afternoon to 4 AM EDT
     Thursday for AMZ152-154.
     Small Craft Advisory until 1 AM EDT Thursday for AMZ156-158.

&&

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