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643
FXUS62 KMHX 200949
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
449 AM EST Mon Jan 20 2025

.SYNOPSIS...
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High pressure builds into the area today. By Tuesday night,
another area of low pressure is forecast to pass well offshore
of the Southeast U.S. coastline and is expected to bring wintry
precip concerns, arctic cold, and gusty winds.
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&&

.NEAR TERM /THROUGH TODAY/...
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As of 245 AM Monday...High pressure will build over the area
through tonight producing cold temperatures and very dry
conditions across eastern NC. Highs today will only be in the
30s which is around 20 degrees colder than normal. A stiff NW
wind, especially early will make it feel lie it`s in the 20s.
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&&

.SHORT TERM /TONIGHT/...
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As of 245 AM Monday...

  - Cold Weather Advisory issued for "Feels Like" temperatures
    below 15 degrees tonight into early Wednesday

Tonight will be very cold even for winter across all of eastern
NC. Arctic air will have settled across eastern NC by late
today with clear skies and very dry conditions with surface
dewpoints only in the single numbers. Under clear skies, temps
will drop into the mid to upper teens. Temps would drop even
lower if not for an occasional light NW breeze overnight. This
light breeze when combined with temps in the teens will make it
feel like it is colder than 15 degrees. Under these conditions,
exposed skin will be susceptible to frost bite, and if not
dressed properly for the extreme cold hypothermia will be
possible. Because of the dangerous cold, a Cold Weather
Advisory has been issued for all of the area from late evening
into early Wednesday.
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&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
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As of 445 AM Monday...

KEY MESSAGES:

 - Very cold air lingers into the first half of the week

 - Confidence in wintry weather Tuesday and Wednesday is high,
   although forecast accumulations continue to come down. A
   second, icier event still looks possible on Thursday.

Tuesday and Wednesday: The main focus remains on the winter
weather risk across our region beginning Tues and running
through Wed morning. Upper level shortwave that will be the
primary driver of this event is currently digging towards the
Four Corners region early this morning and is forecast to
translate east across the Gulf Coast tomorrow and Wednesday.

The past few shifts, we`ve outlined two scenarios of how this
trough could evolve - a more positively-tiled and progressive
through favoring a weaker and faster low, and a slower
negative-tilt trough with implications for a more significant
event. The 20/00z model suite is now sitting firmly in the
weaker scenario, depicting a weak and faster low (or more
accurately a train of weak waves) developing well to our south
and racing along the southern periphery of a strong and dry
Arctic high centered over the TN/OH valleys.

Although the most likely scenario is coming into focus, there
are still details that toss uncertainty into the prognosis. The
biggest is how far towards the coast the high and its dry air
manages to make it, thus denying the deeper moisture needed for
precipitation. The CMC and GFS hold onto this dry air the
longest, preventing any appreciable overlap between the
strongest lift and deepest moisture and rendering less than an
inch of snow, mainly focused along the coast where moisture
profiles are most favorable. The Euro continues to show a little
more expansive area of moisture to work with and remains in the
2-3" camp, although it also continues to modestly trend
downward from prior runs. The overnight snowfall forecast has
followed this downward trend and now shows no more than an inch
storm total. There still remains a healthy range of potential
outcomes, however, ranging from 3-5" to no snow anywhere. Keep
an eye on future forecasts as details continue to come into
focus, and do not anchor on one particular forecast.

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 through Sunday: Guidance continues to come into focus
on the development of a coastal trough along the NC coast on
Thursday into Friday while high pressure remains anchored
inland. Amount of moisture available remains in question here as
well, but thermal profiles suggest if anything does fall a more
predominant freezing rain is likely, at least during the
overnight hours Thurs AM and after the sun sets. During the day
Thur, we should warm up enough to go all liquid. Although this
may keep ice accumulations minimal, black ice may remain an
issue Thurs PM into Fri AM. Kept ZR mention in the forecast but
PoPs in chance range to account for moisture uncertainty.

Dry and relatively milder weather looks to make a return for
the weekend.
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&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
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SHORT TERM /through Tonight/...
As of 245 AM Monday...VFR conditions are expected through the
period as high pressure builds over the area. Gusty NW winds to
20 kt are expected through this afternoon then winds become
light overnight. The dryness of the arctic airmass over eastern
NC should preclude fog formation tonight.

LONG TERM /Tuesday through Friday/...
As of 445 AM Monday...Wintry weather is expected for area
terminals Tuesday PM into Wed AM, with the most likely risk
along coastal terminals. Primarily precip mode is -SN, and mild
accumulations may reach up to an inch. Snow will likely
introduce IFR visibility and cig issues especially after 00z
Wed. VFR briefly returns Wednesday, but a second coastal trough
may bring another round of wintry precip, primarily FZRA, before
turning all liquid during the daytime hours. Details on this
system still remain very murky and confidence in its evolution
remains low.
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&&

.MARINE...
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SHORT TERM /through Tonight/...
As of 245 AM Monday...The Gales have been lowered to SCA,s
which are now in effect for all eastern NC waters. Hazardous
marine conditions continue this morning with improving
conditions this afternoon and early evening as high pressure
builds in and winds diminish in response. Winds have already
begun to diminish this morning so all of the Gale Warnings have
been lowered to SCA`s with winds forecast to further decrease
tonight. Currently, NW winds 15-25 kt this morning will continue
to diminish to 10-20 kt late today and tonight. Seas 5-9 ft
this morning subside to 3-5 ft late today and 2-4 ft tonight.

LONG TERM /Tuesday through Friday/...
As of 450 AM Monday...Weak wave of low pressure is forecast to
pass well to our south tomorrow as strong and dry high pressure
builds into the area from the northwest. Resulting pressure
gradient will introduce widespread SCA across area waters Tues
PM into Wed, although probability of Gales has fallen
considerably over the past couple of forecast cycles. A
secondary coastal trough is forecast to develop Thurs night into
Fri which may introduce a period of elevated seas at the end of
the period, but evolution of this system remains of low
confidence.
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&&

.MHX WATCHES/WARNINGS/ADVISORIES...
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NC...Cold Weather Advisory from 10 PM this evening to 10 AM EST
     Tuesday for NCZ029-044>047-079>081-090>092-094-193>196-
     198-199-203>205.
MARINE...Small Craft Advisory until 7 AM EST this morning for AMZ131-
     136-137-230-231.
     Small Craft Advisory until 10 AM EST this morning for AMZ135-
     156-158.
     Small Craft Advisory until 4 PM EST this afternoon for AMZ150-
     152-154.
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&&

$$

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