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Area forecast discussion 
National Weather Service Newport/Morehead City NC
350 PM EST sun Dec 28 2014

Synopsis...
a cold front will move through eastern North Carolina tonight and
push off the coast Monday. High pressure will build in from the
west Tuesday and remain over the region through late week. A
cold front will approach the region Saturday into Sunday.

&&

Near term /through tonight/...
as of 230 PM sun...broad upper level trough over the majority of the
country with high pressure over the southeast. Short wave rounding
the base of the trough over Texas will shear out as it approaches
eastern North Carolina tonight. Models have come into good agreement
on the timing of the associated cold front expected to move through
the area tonight after midnight...to be along the coast around
sunrise. Cross sections showing best moisture and lift along and
behind the front. Forecast soundings showing most of the moisture
ahead of the front confined to below 700mb for light prefrontal
precipitation. Cloud cover and timing of front will affect nighttime
low temperatures...am expecting upper 40s in the west and north with
lower 50s over the remainder of the area.

&&

Short term /Monday/...
as of 230 PM sun...front will be along the coast around sunrise
Monday morning with mainly northerly flow over the inland areas.
Models remain in good agreement in stalling the front near the coast
through the day. Forecast soundings show a saturated column through
the day. Will continue the high probability of precipitation forecast as weakened upper
level energy moves over the area through the southwesterly flow. Cold air advection
in northerly surface flow behind the front and cloud cover will help
keep high temperatures in the middle 50s.

&&

Long term /Monday night through Sunday/...
as of 330 PM sun...a cold front will stall across the offshore
waters Monday night and Tuesday with flow aloft becoming west-southwest. A strong
Post frontal inversion with abundant low level moisture continues
Monday night and Tuesday as weak low pressure develops along the stalled
frontal boundary offshore continuing to bring low clouds with
periods of drizzle or light rain. The 12z NAM continues to be an
outlier by developing strong low pressure and more widespread rain
across the region Tuesday. Should begin to see improving conditions
late Tuesday afternoon as drier air filters in associated with high
pressure building in from the west. Highs Tuesday generally in the
middle/upper 40s along the coastal plain with lower 50s along the
coast/obx.

High pressure builds across the area Wednesday through Friday bringing dry
conditions and seasonably cool conditions. Wednesday will be the coolest
day this period with highs in the middle to upper 40s...then will see
the airmass gradually moderate Thursday and Friday with highs in the
50s. Lows Wednesday and Thursday in the upper 20s inland to 30s coastal
sections. Increasing cloud cover expected to hold min temperatures to
the 30s inland and 40s coast Friday.

12z models only indicate slight agreement for the late week
system developing across the Southern Plains and Gulf states.
Onset of precipitation still appears to be late Friday into Sat as a warm
front lifts north through eastern NC. Warm air advection and increasing moisture
could bring a few showers across the region late Friday night with
increasing precipitation chances Sat. The 12z European model (ecmwf) continues to be more
amplified in the middle levels but remains much slower and farther
south with its southern stream shortwave. The 12z GFS continues
its previous trend of dampening the midlevel support with a weak
front stalled across the region Sat night through Sun night. The
European model (ecmwf) has some support from the 12z Gem and thus have hedged
closer to a European model (ecmwf) blend with previous forecast and wpc. Chance
probability of precipitation expected Sat through Sun night with temperatures above climatology
as warm air advection/increased low level thicknesses build maximum temperatures into the
middle 60s this weekend.

&&

Aviation /20z Sunday through Friday/...
short term /through 18z Monday/
as of 100 PM Sunday...VFR conditions to start as an area of low
pressure approaches the area. Rain falling in central NC will
shift eastward through the afternoon/evening. The low will move
across central NC this evening and then off the Virginia coast. This
will bring in a backdoor cold front and strong surface inversion with
north winds felt across the region by early morning Monday. This
inversion will keep moisture trapped in the lowest levels through
the remainder of the period. Given this...IFR conditions expected
just after midnight. Visibilities will also reduce due to fog and rain
after around 06-09z. LIFR conditions for both ceilings/visibilities can not
be ruled out by the morning hours Monday. With little flow and
another impulse moving across the area...do not anticipate visibilities
or ceilings to improve much during the day Monday.

Long term /Monday night through Friday/...
as of 340 PM sun...overrunning moisture will continue to bring
periods of light rain/drizzle. IFR/LIFR stratus with areas of
drizzle and possibly occasional periods of light rain into midday
Tuesday before conditions improve to VFR from west to east. High
pressure builds across the area Wednesday and Thursday then shifts offshore
late Friday with VFR conditions dominating.

&&

Marine...
short term /through Monday/
as of 230 PM sun...southwesterly flow ahead of an approaching cold
front will continue over the North Carolina coastal waters this
evening. Gradient will be loose for speeds around 10 knots. As front
approaches from the northwest...gradient will tighten a bit picking
speeds up to 10 to 15 knot by late evening. Models in good agreement
that front will drop from north to south through the waters from
around midnight to around sunrise.

Gradient behind the front will tighten Monday morning...helping wind
speeds to increase to 15 knots during the day. This will bring the
seas to 3 to 4 feet during the afternoon hours. Front will stall
east of the North Carolina coastal waters and as high pressure well
to the west noses into the area...gradient will continue to
increase...bringing speeds to 15 to 20 knots and seas 3 to 5 feet by
sunset. Expect conditions to remain below Small Craft Advisory
criteria through Monday.

Long term /Monday night through Friday/...
as of 345 PM sun...a cold front is will stall across the offshore
waters Monday night into early Tuesday. Weak low pressure develops along the
front with strong high pressure building in from the west Tuesday
allowing north/NE winds to increase to 15-25 knots through Tuesday evening.
Seas build to 4-7 feet north of Ocracoke and 3-6 feet south Tuesday/Tuesday
night in response. Hoisted small craft advisories with the
afternoon package for the coastal waters and Pamlico Sound...though
if trends indicate slightly stronger winds then the Albemarle
Sound may be added. Continue to discount the NAM solution Tuesday
into Wednesday as it is an outlier developing stronger low off the coast
with winds near gale force late Tuesday. Winds and seas gradually
subside late Tuesday night and Wednesday as high pressure builds in from the
west. The high will shift through the waters Thursday and off the
NC coast Friday. North winds at or below 15 knots Wednesday becomes westerly
Thursday. Seas prognosticated to subside to 2-5 feet Wednesday and 1-3 feet Thursday into
Friday.

&&

Mhx watches/warnings/advisories...
NC...none.
Marine...Small Craft Advisory from noon Tuesday to 3 am EST Wednesday
for amz135-156-158.
Small Craft Advisory from 9 PM Monday to 7 am EST Wednesday
for amz150-152-154.

&&

$$
Synopsis...dag
near term...cgg
short term...cgg
long term...sk/dag
aviation...dag/Lep
marine...cgg/dag

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