New Bern, North Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

765
FXUS62 KMHX 180939
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
439 AM EST Sat Jan 18 2025

.SYNOPSIS...
A weak coastal low will pass offshore today into tonight,
followed by a stronger low moving through on Sunday. A strong
cold front then pushes through the area Sunday night. High
pressure then builds in on Monday. By mid-week, another area of
low pressure is forecast to pass well offshore of the Southeast
U.S. coastline.

&&

.NEAR TERM /THROUGH TODAY/...
As of 300 AM Saturday...A dampening shortwave moving through
the central and southern Appalachians will induce low pressure
development off the SE coast today. Guidance continues to
strongly indicate that this low will remain offshore as it lifts
NE and eventually well out to sea tonight.

Initial precipitation will start out as an area of scattered
showers offshore 9-12Z which will move along the coast early
this morning. A more widespread area of rain will develop along
the coastal plain and move across all of eastern NC this
afternoon. This rain is forecast to dissipate before 00Z this
evening. The heaviest precipitation today (up to 0.50") is
expected east of Highway 17 with lesser amounts to the west.
Decent WAA plus a modest southerly flow will help boost temps
into the 50s.

&&

.SHORT TERM /TONIGHT/...
As of 300 AM Sat...Yet another area of rain will develop over
South Carolina this evening then spread northeast across all of
eastern NC after midnight as the next area of low pressure forms
over the Carolina Piedmont and begins to track northeast toward
the NC coast late tonight. An additional 1/4 to 1/2" of
rainfall is expected by 12Z Sunday with this area of
precipitation. Lows will be mild in the 40s overnight.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
As of 435 AM Saturday...

KEY MESSAGES:

 - Notable arctic airmass to invade ENC next week

 - Confidence in wintry weather is moderate-to-high for next
   week

Sunday: On Sunday, yet another upper level wave will glance the
area, and will once again spur on cyclogenesis, leading to the
development of a secondary area of low pressure. The track of
this low looks to be further inland as it runs NE from southern
Alabama through eastern North Carolina. This inland track should
help keep temps on the milder side for one more day, which also
favors all liquid during the daylight hours Sunday. As the low
moves up the Mid-Atlantic Coast, it will deepen, allowing strong
CAA to ensue across ENC. This continues to look like a cold-
air-chasing-the-moisture scenario, with rain showers possibly
ending as a brief period of snow showers across portions of the
Albemarle Sound. Ensemble guidance has slowly moved away from
this idea, and although an isolated flake or two is not
impossible opted to make the forecast all liquid this morning.

Monday - Wednesday: In the wake of Sunday`s cold front, an
arctic airmass will ooze south and east out of Canada and
blanket much of the U.S. east of the Rockies for several days.
Meanwhile, an upper level shortwave will dive southeast along
the Rockies on Monday, then translate east across the Gulf Coast
States Tuesday or Wednesday. Medium range guidance are in solid
agreement with the wave as it dives through the Rockies.
However, more notable differences begin to show up as it crosses
the Gulf Coast States. If the main question on previous shifts
was whether it would snow or not, the 00z guidance (both
deterministic and ensemble) has now shifted the challenge to how
much snow will fall. The two scenarios outlined yesterday
remain:

SCENARIO #1 - The upper wave remains positively-tilted, and
progressive, as it traverses the Southeast U.S. This scenario
favors a weaker, faster, and more suppressed, low track from the
Gulf of Mexico east into the SW Atlantic. This scenario
supports the potential for a glancing swath of light,
accumulating snow, across parts of ENC, with the greatest risk
along the coast, and a decreasing chance further inland. In an
extreme case, the low may end up being too far suppressed to the
south and ENC would remain cold and dry with little winter
precip. Although this remains the most likely scenario, it has
ceded some ground in probability to the second scenario:

SCENARIO #2 - The upper wave slows down as it emerges out of the
Southern Rockies, and takes on a negative tilt before translating
across the Southeast U.S. This scenario favors a deeper surface low
over the Gulf, with a subsequent track closer to the Gulf and
Southeast U.S. coastline. For ENC, this would be the more impactful
scenario, as it would potentially open the door for a period of
moderate to heavy wintry precip. If a deeper low tracks too
close to the coast, however, that could introduce more warmer
air and less wintry weather, especially along the water. The
mod/heavy winter precip scenario has gotten a little more
ensemble support this morning, along with the 00Z ECMWF which
made a rather astonishing flip-flop from a suppressed low-snow
forecast at 17/12z (although a 1-run change does not
necessarily mean a trend).

In addition to potential snowfall, strong northerly winds are
forecast to develop as the pressure gradient north of the parent
low quickly tightens, and some ensemble members suggest gusts in
excess of 35 mph are plausible. If this does occur along with
any amount of snow, blizzard conditions may develop with the
highest risk along the Outer Banks. At this point the
probability of this is low (less than 20%).

All of the listed scenarios remain on the table this forecast,
and an ensemble of ensembles does not yield any clearly favored
forecast. The shortwave driving this whole system has a long
way to go, and it will likely be at least a couple days further
until details come into focus. Model output will likely continue
to change until that time, sometimes drastically, and we
therefore urge all to not concentrate on single model runs. Our
message remains the same: there is moderate-to-high confidence
in a winter weather event on Tuesday and Wednesday, but its
intensity remains highly uncertain and the range of potential
snowfall amounts is very large. Please continue to stay tuned
through the weekend and into next week.

The most confident aspect of the forecast is the anomalously
cold airmass. A stretch of unusually cold temperatures still
appears likely, with record or near-record temperatures very
much on the table. If it verifies, it will be one of the
coldest stretches for our region since the January 2018 cold air
outbreak. If we get any accumulating snow, forecast low
temperatures could easily be 3-5 degrees lower than currently
advertised. This prolonged stretch of cold has the potential to
take its toll on pipes and other infrastructure not accustomed
to this magnitude of cold. Precautions are strongly recommended
in preparation of this stretch of cold weather.

Thursday and Friday: Guidance is in loose agreement that yet
another strong shortwave will dive out of the Rockies at the end
of the week with the potential for yet another another coastal
low to develop off the coast. To emphasize a fundamental rule of
numerical weather prediction - error compounds the farther into
a forecast you go. Because of the high uncertainty with the
precluding storm system, there is little confidence beyond the
presence of a weak signal. PoPs are capped at low- end chance
with a vague mention of winter precip as Arctic airmass remains
locked in place.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /through Tonight/...
As of 300 AM Sat...Pred VFR conditions are expected through
early this evening. An area of light rain will move through this
afternoon but ceilings and visibilities are forecast to remain
at VFR levels. By late evening widespread low clouds with
ceilings lowering from MVFR to IFR are expected to develop after
00Z along with areas of fog. An area of rain will then move
through the area after midnight helping to maintain sub VFR
conditions overnight. Winds will continue to be light through
the period.

LONG TERM /Sunday through Wednesday/...
As of 425 AM Saturday...Scattered to numerous SHRA are expected
Sunday as a pair of low pressure systems track across the
region. By Sunday night, cold air wrapping into the area may
allow a change from SHRA to SHSN although this will likely
remain north and east of area terminals. Periods of low CIGS and
low VIS are expected over the weekend, with the greatest risk
of IFR, or lower, conditions coming on Sunday. Gusty northwest
winds will be possible with a cold front as it moves through
Sunday night. A drier airmass moves in on Monday with VFR
conditions and lighter winds expected. Looking ahead, there is a
moderate chance of wintry weather Tuesday or Wednesday of next
week, along with the potential for IFR, or lower, conditions.
Stay tuned as we continue to evaluate this potential impact to
aviation.

&&

.MARINE...
SHORT TERM /through Tonight/...
As of 300 AM Sat...For the most part this morning, winds are
light SE to S 10 kt or less except for the outer southern and
central waters where they are 10-20 kt due to warmer SST`s.
Expect these conditions to persist throughout today with lighter
flow near shore and stronger winds offshore. Winds will briefly
become W to NW this afternoon as developing low pressure tracks
off the coast. Tonight winds will be W to SW 10-15 kt. Seas
will continue 2-4 ft through tonight.

LONG TERM /Sunday through Wednesday/...
As of 430 AM Saturday...A pair of low pressure systems will
move northeast through the ENC waters, leading to an increased
risk of showers, elevated winds, and elevated seas. The highest
risk of SCA and/or gale-force winds appears to be late Sunday
into Monday as the deepest of the two lows moves through. A Gale
Watch has been hoisted for the waters south of Oregon Inlet, and
SCA are likely to follow in coming shifts for remaining waters.
High pressure eventually builds in later Monday into Monday
night with some improvement to boaters for a brief time, before
a second low passes well to our south and east introducing a
second, more widespread Gale across area waters.

&&

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

&&

$$

SYNOPSIS...MHX
NEAR TERM...JME
SHORT TERM...JME
LONG TERM...RM/MS
AVIATION...JME/MS
MARINE...JME/MS