Greenville, North Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

433
FXUS62 KMHX 231153
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
653 AM EST Mon Dec 23 2024

.SYNOPSIS...
High pressure continues building in today bringing cold, dry
conditions. A weak area of low pressure will pass along the NC
coast Christmas Eve bringing rain and deteriorating marine
conditions. High pressure then rebuilds into the area through
the remainder of the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 645 AM Monday...Cold morning with apparent temperatures in
the mid to upper teens over much of mainland ENC. Today, high
pressure over New England will continue to shift eastward and
offshore, while upper ridge gradually builds over the Carolinas.
Temps will remain below normal, with highs in the mid 40s to
low 50s. The NE flow will likely keep sct-bkn scu along OBX with
mostly sunny skies elsewhere.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
As of 330 AM Monday...

Key Message:

-30% chance of light freezing rain impacting Western Martin
 County early Tuesday morning

High pressure to our north continues moving further away from
us offshore, and coastal trough offshore strengthens, eventually
forming a weak coastal low. This coastal low will bring moisture
in the form of cloud cover and then precip into the region
in the short term. Before the cloud cover moves in, we do have a
couple hour period after sunset where skies remain clear in the
coastal plain, which paired with light to calm winds could
result in a solid radiational cooling setup. Wherever we are
forecasting clear skies before midnight, I leaned heavily on
the lower end of temperature guidance to account for this rapid
radiational cooling potential. While this seems benign, the
temperatures we see along the coastal plain during the short
term will influence freezing rain potential tonight.

Hi-res guidance indicates precip moving into the region from
the south as soon as midnight tonight. However, we have a
substantial dry layer at around 5kft, and while cloud cover will
increase, precip will be hard pressed to reach the surface as
soon as high res guidance is suggesting. Through the early
morning hours, evaporative cooling will allow this dry layer to
moisten and cool a tad, before we get our surge of mentionable
PoPs after 3am. The initial precip from this system will be
moving into a departing cold airmass from the past couple of
days. Forecast sounding show a very shallow cold layer, with
wet-bulb temps around 31-33F across portions of the coastal
plain Monday night. Temps aloft will be very warm (5-10C), so
frozen precipitation (ie. sleet/snow) is not expected. However,
the lower temps from radiational cooling to start the night
mentioned before could keep the surface layer below freezing at
the onset of precipitation. Depending on how quickly the precip
moves in, and how cold we get ahead of the precipitation, there
could be a very brief (2-4 hr) period of light freezing rain
between 4AM-8AM NW portions of the CWA. With this forecast
update, we have a 20-30% chance of seeing light freezing rain
early tomorrow morning along the western half of Martin County
(near and west of Williamston), and the northwestern edge of
Pitt county (Bethel). Ice accumulation totals are expected to
remain around 0.01", meaning impacts will be on the more minor
side. It is worth noting that even with light rain at 33F,
there is a scenario where the cold rain falls on roads
(including bridges) with cold temps from the recent cold snap,
and this could lead to some slick spots on roads and pavement,
even where air temps aren`t below 32F.

Lows tonight are around 30 inland, 40s for beaches, lowest
around 12AM-3AM before beginning to increase with cloud cover
moving in.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
As of 330 AM Mon...

KEY MESSAGES

*Light rain is expected Christmas Eve as a weak area of low
pressure moves along the NC coast.

*High pressure then builds in behind this system on Christmas
with dry and milder conditions expected

*Dry weather continues the rest of the week with moderating
 temps. Next chance of rain possible this weekend.

Tuesday...A weak area of low pressure will move along the NC
coast Christmas Eve with light rain falling for most of the day.
Best chances of rain will be along the coast where up to a 1/4"
of rain could fall. Well below normal temperatures will continue
as widespread clouds and northerly flow keep temps mostly in the
40s all day.

Wednesday through Friday...High pressure will build in behind
this system on Christmas with drier but still cool conditions
expected. Highs will range from the around 50 degrees across
the northern OBX to the mid 50s south of US 70 under partly
cloud skies.

High pressure will continue to ridge down the Eastern Seaboard
through Friday with mostly dry conditions persisting. A weak
coastal trough will likely form, and a few widely scattered
showers will be possible across the immediate coast and beaches.
Temperatures will continue to moderate with highs in the mid to
upper 50s expected both Thursday and Friday.

Saturday and Sunday...Some model spread remains for this
weekend, but the majority of forecast guidance shows the coastal
trough strengthening and moving nearshore ahead of a developing
low pressure system approaching from the west. Expect widely
scattered showers across Eastern NC on Saturday, and then Sunday
has the potential to be more unsettled depending on the timing
of an approaching cold front. Conditions will continue to
moderate with highs in the low to mid 60s likely.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SHORT TERM /through 12Z Tuesday/...
As of 645 AM Monday...VFR flight cats expected through the
evening and the first half of tonight with high pressure to our
north. Light winds from the north continue today. Low level
cloud cover and rain chances start moving into the region 6Z
onwards as a coastal trough offshore spins up a weak coastal
low. MVFR ceiling chances rise through the early morning hours,
as the low level gradually moistens. There is a low-end risk
(20%) of IFR ceilings before 12Z Tuesday, although just beyond
this TAF period chances to seem to increase. Worst aviation
conditions are expected for coastal terminals (including OAJ,
EWN). ISO and PGV will be further away from the center of the
coastal low, and while drops to MVFR are expected, they will be
hard pressed to reach IFR based on the current guidance.
Rainfall associated with the developing coastal low could result
in drops to visibility, but with the heaviest rain expected
after 12Z, added -RA with this TAF issuance but have not
indicated any reductions in visibility at this time.


LONG TERM /Tuesday through Friday/...
As of 330 AM Mon...Sub- VFR conditions are likely for most of
Tuesday as a weak low passing by just off the NC coast provides
a sizable area of light rain and low clouds across Eastern NC.
Thereafter, conditions should be mostly VFR through Friday with
high pressure over the area.

&&

.MARINE...
SHORT TERM /through Monday night/...
As of 400 AM Monday...North winds 10-20 kts with some gusts in
the lower 20s are observed across waters, with seas generally
3-5 ft, with some occasional 6 footers possible along the gulf
stream. Today, north winds remain 10-20kt, with the occasional
gust up to 25 kt along the Gulf Stream. Seas remain generally
3-5 ft, with 2 footers expected right offshore of the Crystal
Coast.

Tonight, seas fall to 2-4 feet, with winds remaining 10-20kt
from the north. A coastal trough brings slight chances of rain
offshore of Hatteras Island, before more widespread rainfall
moves in during the morning Tuesday.



LONG TERM /Tuesday through Friday/...
As of 330 AM Mon...Winds will increase quickly Tuesday morning
as an area of low pressure passes through the coastal waters.
SCAs have been issued for the coastal waters south of Oregon
Inlet where winds will gust 25-30 kts and seas build above 6 ft.
Small craft conditions will eventually reach the northern waters
and possibly the Pamlico Sound Tuesday night, but given the long
time range will hold off on any Advisories for these areas for
now.

Behind the low pressure, a strong pressure gradient will keep
winds at 20-30 kts out of the north through Wednesday morning.
Winds will then subside slightly to 15-25 kts later Wednesday,
and eventually become NNE/NE at 10-20 kts Thursday and Friday.
Seas will rise to 5-7 ft south of Cape Hatteras by Tuesday
afternoon, with 3-5 ft seas to the north. Eventually 5-7 ft seas
will spread to all waters by Tuesday night. Seas begin to
subside slowly Wednesday to 3-5 ft, except for the outer
portions of the waters south of Cape Hatteras where seas will
remain 4-6 ft for most of the day. 3-5 ft seas are then expected
Thursday and Friday.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...Small Craft Advisory from 7 AM Tuesday to 10 PM EST Wednesday
     for AMZ152-154.
     Small Craft Advisory from 7 AM Tuesday to 7 PM EST Wednesday
     for AMZ156-158.

&&

$$

SYNOPSIS...MHX
NEAR TERM...
SHORT TERM...RJ
LONG TERM...SGK
AVIATION...SGK/RJ
MARINE...SGK/RJ