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Area forecast discussion 
National Weather Service Newport/Morehead City NC
1006 PM EDT Friday Sep 19 2014

Synopsis...
high pressure will ridge into the region from the north through
Saturday. Low pressure will move northeast Sunday just off the
coast. A cold front will move through Monday. High pressure behind
the front will pass by to the north Tuesday and Wednesday.

&&

Near term /tonight/...
as of 10 PM Friday...minor adjustments made to temperature/dew point
trends as temperatures continue to drop. Trimmed back probability of precipitation along the coast to
schc along the southern waters. Clouds will continue streaming in
from the south as a low pressure system develops off the SC
coast. Lows still prognosticated to be in the low 60s inland to around 70
along the immediate coast.

Previous discussion...high pressure will continue to ridge into
eastern NC overnight while low pressure develops late off the
Florida coast along a stationary boundary. As the low forms it
will push an inverted trough toward the coast which could help to
trigger a few showers near or just inland the southeast coast.
Otherwise expecting generally a quiet night weather wise across
the area with only some passing cloudiness. Lows should be similar
to last night ranging from around 60 inland to the upper 60s to
around 70 along the coast.

&&

Short term /Saturday/...
as of 315 PM Friday...trough remains in place along the coast just
inland and will likely merge with a sea breeze. With weak upper
trough in place and low off the southeast coast deepening and slowly
beginning to lift north expect the chance of rain to increase
through the day on Saturday and migrate inland a bit. Still do not
expect high chance of precipitation across the area. Did raise probability of precipitation
slightly across inland areas to slight chance with 30 probability of precipitation along
the coast. Increasing clouds will keep highs generally around 80s
degrees across the area.

&&

Long term /Saturday night through Friday/...
as of 3 PM Friday...surface low pressure along with a middle-level
trough will move just off the Carolina coast during Saturday night
and Sunday morning. Will maintain low chance probability of precipitation for this time
frame as good agreement continues amongst the GFS/European model (ecmwf) and nam12.
A strong cold front moves across the area around midday Monday
accompanied by the deepening middle-level trough. Have included small
chances of showers to accompany the front mainly Monday morning.
With weak upper level flow and strong high pressure ridging south
from the Great Lakes and New England...expect cooler and dry
weather for Tuesday and Wednesday. Some minimum temperatures
inland could drop to the middle 50s by Wednesday morning with daytime
highs generally in the middle/upper 70s. The 12z European model (ecmwf) and GFS now
showing better agreement in showing light precipitation spreading
back into the County Warning Area from the south and east Thursday into Friday in
association with an inverted trough moving toward the coast. Have
accordingly gone with low probability of precipitation Thursday into Friday with an
increase in cloud cover.

&&

Aviation /02z Saturday through Wednesday/...
short term /through Saturday/...
as of 655 PM Friday...expecting a mainly VFR forecast through the
period with considerable middle and high cloudiness. There is the
potential for winds to decouple late across the north affecting
mainly kpgv and perhaps kiso. If this occurs there will be a brief
window for MVFR visibilities to develop in light fog if skies
were to clear. Will include in the kpgv taf but leave out of the
remainder as winds are not expected to fully decouple overnight.
On Saturday moisture will deepen across eastern NC as developing
low pressure moves along the Gulf Stream. This system could
produce a few showers but they are expected to occur mainly east
of the taf sites.

Long term /Saturday night through Wednesday/...
as of 3 PM Friday...anticipate periods of MVFR ceilings/visibilities
Saturday night into Sunday...especially at kewn/koaj...as clouds and
some light precipitation associated with low pressure moving up
the coast may lower conditions at times. A few showers will
accompany a strong cold front as it crosses the region by midday
on Monday. Dry high pressure will build over the region with
mostly VFR conditions expected Tuesday and Wednesday.

&&

Marine...
short term /tonight and Saturday/
as of 10 PM Friday...extended Small Craft Advisory for the Pamlico Sound
until 06z due to frequent gusts to 25 knots. Seas 4 to 6 feet across
the coastal waters with gusty NE winds around 15-20 kts with
higher gusts.

Previous discussion...persistent moderate easterly flow continues
over the waters this evening as high pressure builds in from the
north. Winds will back to the northeast overnight as an area of
low pressure develops off the southeast coast and slowly moves
north while high pressure weakens over the Atlantic and shifts off
to the northeast by late Saturday. Followed a blend of NAM/GFS
through the period shaded towards persistence forecast. Did lower
the winds slightly Saturday which slightly delays the onset of Small Craft Advisory
conditions due to long fetch easterly winds across the northern
waters. Winds of 15 to 20 knots with gusts to 25 knots across most of
the waters tonight will tend to hover around 15 knots through the day
on Saturday. Seas will generally be 4-6 feet through the
period...highest around Diamond Shoals....where we could see seas
reach 7 feet early tonight. Based on latest ww3 and local nwps it
looks like seas will drop below 6 feet across the waters south of
Ocracoke Inlet by Saturday morning so cut the Small Craft Advisory off at that time
for the southern waters.

Long term /Saturday night through Wednesday/...
as of 305 PM Friday...based on latest wave guidance from local
nwps/Swan model...have opted to have small craft advisories
continue on all coastal waters through the day Sunday as surface
low moves along the North Carolina coast. The low moves away with
flow becoming more offshore by Sunday night. Winds back to SW by
late Sunday night then veer to north behind a strong cold front
as it drops across the waters by midday Monday. As high pressure
strengthens over southern New England (1030 mb+) around
midweek...long fetch northeast winds and an increasing gradient
will lead to additional small craft advisories starting on
Wednesday and perhaps into next weekend.

&&

Mhx watches/warnings/advisories...
NC...none.
Marine...Small Craft Advisory until 2 am EDT Saturday for amz135.
Small Craft Advisory until 8 PM EDT Sunday for amz152-154.
Small Craft Advisory until 6 am EDT Saturday for amz156-158.
Small Craft Advisory from 10 am Saturday to 8 PM EDT Sunday
for amz150.

&&

$$
Synopsis...rsb
near term...rsb/jme/Lep
short term...rsb
long term...ctc
aviation...ctc/jme
marine...rsb/ctc/jme/Lep

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