533
FXUS62 KMHX 120825
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
425 AM EDT Sun May 12 2024

.SYNOPSIS...
High pressure builds across eastern NC today behind a departing
cold front, remaining in control into Monday despite a weak
backdoor front crossing the region tonight. Then, a low
pressure system will bring unsettled weather across the area
Tuesday into Wednesday. High pressure builds in on Thursday
before another low pressure system impacts us late in the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 230 AM Sun...Latest analysis this morning depicts
barotropic upper level trough situated over southeastern Canada
as a shortwave trough pivots across the eastern OH Valley, with
predominantly westerly flow across the Carolinas. To the west,
ridging is amplifying over the southern plains as another upper
level low digs into the Four Corners region. At the surface,
cold front associated with the Great Lakes low is pushing across
the Appalachians while a pre-frontal trough is driving a band
of mid-level clouds across ENC. Radar is showing a few very
light returns from Richlands to Fayetteville but a lack of
confirming ground observations point to this likely being virga,
or very light sprinkles at best.

Cold front will quickly push across the area this morning as
shortwave traverses the mid-Atlantic, allowing high pressure to
build in its wake. Breezy downslope WSW flow, combined with
increasing low-level heights in the wake of the upper trough,
favor temperatures rebounding into the mid to upper 70s on a
mainly sunny and dry Sunday. Across the northern Outer Banks,
temperatures will not be able to climb quite as high as a weak
backdoor cold front, associated with a very weak wave of low
pressure dropping southeast out of the Delmarva Peninsula,
pushes across the area.

RHs this afternoon plummet to between 25-30% especially across
the coastal plain, but given recently saturated soils fire
conditions will be marginal.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
As of 230 AM Sun...Deep ridging will continue to expand over
much of the southeastern CONUS tonight into Monday morning as
mid- Atlantic trough pushes further offshore and Four Corners
low digs further into the southern Plains states. High pressure
will settle overhead as the backdoor front traverses the area
and eventually washes out, promoting calm winds and clear skies.
This pattern strongly favors a low temperature forecast below
guidance given excellent radiational cooling, and would not be
surprised to see a multitude of readings in the upper 40s across
the coastal plain early Mon morning. Patchy radiation fog is
possible to start the morning work commute, but widespread
visibility issues are not anticipated.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
As of 330 AM Sunday...Dry and seasonably cool weather will
continue Monday as high pressure builds across the area.
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.

Monday and Monday night...High pressure will become centered
off the Mid-Atlantic will migrate offshore on Monday while
ridging builds aloft. Dry conditions will continue but clouds
will be increasing through the day as the next system approaches
from the west. Temps will be seasonable with highs in the upper
70s/lower 80s. Dew points will be much below normal however in
the low to mid 50s making for very comfortable conditions.

Tuesday through Wednesday night...Vertically stacked low
pressure will track across the Ohio River Valley on Tuesday and
then push across the Mid-Atlantic on Wednesday before pushing
off the coast Wednesday night. Precip chances increase through
the day Tuesday and peak Tuesday night as upper level diffluence
and southern stream moisture increases across the area with
PWATs peaking around 1.75". Additional showers will push across
the area Wednesday as the upper level trough and attendant sfc
cold front pushes across the area. Could see a few elevated
thunderstorms Tuesday into Tuesday night but clouds and precip
will limit instability and any severe potential appears minimal.
However, Wednesday will have 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.
Most of the area will likely see a soaking rain with precip
amounts around 1-1.5" through the period with coastal sections
potentially approaching 2". Temps will continue to be
seasonable with highs in the mid 70s to around 80 Tuesday and
low to mid 80s on Wednesday.

Thursday through Friday...Disparity continues among the models
with how the mid week system transitions as it moves offshore
late Wednesday with some solutions opening the upper low into a
wave with the system progressively moving east into the western
Atlantic allowing for upper ridging to build aloft bringing a
dry forecast. However, the 00z operational ECMWF and to some
extent the CMC now maintain a closed low with a slower track
across the Mid-Atlantic on Thursday keeping cyclonic flow over
the area which will bring greater cloud cover with a few showers
persisting across the area. Have now introduced slight chance
PoPs and the CMC is trending toward the ECMWF. Models are in
better agreement with another southern stream 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. But despite the differences, most
guidance brings another round of descent rainfall amounts across
much of the area.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /through 06z Monday/...
As of 140 AM Sun...The probability of sub-VFR flight conditions
over the next 24 hours is less than 10%.

VFR conditions prevail across all areas early this morning as a
weak pre-frontal trough and associated cloud cover (confined
above 7 kft) push across ENC. Clear skies are expected to
prevail immediately behind this boundary and prevail through
most of the day, although some modest cu field development is
possible in the afternoon. Breezy WNW winds expected this
afternoon with gusts up to 25 kt possible across the coastal
plain. Across the northern Outer Banks, a secondary front will
cross the area late this afternoon as a weak area of low
pressure passes offshore bringing further veering of winds to
the north and eventually northeasterly into the overnight hours.

After sunset, winds will rapidly decouple under clear skies as
high pressure moves overhead. Some patchy radiational fog is
possible at the most vulnerable sites, but odds of anything
impactful to operations are very low - less than 10%.

LONG TERM /Monday through Thursday/...
As of 4 AM Sunday...Pred VFR conditions expected through Monday
as high pressure builds across the region. A low pressure
system will impact the area Tuesday through Wednesday with
deteriorating conditions expected Tuesday 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.

&&

.MARINE...
SHORT TERM /Today and Tonight/...
As of 315 AM Sun...Improving marine conditions expected through
the short term, although multiple frontal passages will bring
quick wind regime changes over the waters through tomorrow
morning.

Regional observations show south to southwesterly winds of 5-10
kt with seas 3-5 feet (except 2-3 feet across Onslow Bay) as a
pre-frontal trough and cold front approach the waters from the
west. The primary cold front is expected to cross the waters by
sunrise, accompanied by a west-northwesterly surge of around 15
kt with a few gusts exceeding 20 kt this morning. By this
afternoon, a weak wave of low pressure moving off the Delmarva
Peninsula will drag a subtle backdoor cold front across the
waters, veering winds northerly and then easterly through
tonight. Winds are expected to weaken behind this boundary to
around 10 kt or less.

Currently observed seas will change little into the afternoon as
winds pick back up out of the west, but once the backdoor front
pushes through lighter winds will allow seas to subside, falling
to around 2-3 feet areawide by Mon morning. No SCA headlines are
needed this morning although a few spotty gusts to 25 kt are
possible (10-20% chance) across portions of the sounds this
morning.

LONG TERM /Monday through Thursday/...
As of 415 AM Sunday...High pressure builds moves offshore
Monday while a low pressure system will impact the waters
Tuesday into Wednesday. Low pressure may linger near the coast
into Thursday.

Easterly winds around 15 kt or less continues into Monday with
seas around 2-4 ft. Winds veer to southerly Monday night and
increase Tuesday ahead of the low pressure system and expect a
period of Small Craft Advisory conditions to develop and
continue into Wednesday. We may see a brief period of Gale Force
winds across portions of the waters Tuesday evening. Seas will
build Tuesday and peak around 7-10 ft Tuesday night, then will
gradually subside Wednesday and Wednesday night. A cold front
will push across the waters with winds becoming NW to N around
10-15 kt and seas around 3 to 5 ft.

&&

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

&&

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