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Area forecast discussion 
National Weather Service Newport/Morehead City NC
300 am EDT Thursday Aug 21 2014

Synopsis...
a weak front will linger across the area today...lifting to the
north tonight. The front will finally push through Friday night
into early Saturday. High pressure will extend south into the
region Sunday into early next week.

&&

Near term /through today/...
as of 3 am Thursday...latest surface analysis shows weak frontal boundary
bisecting the County Warning Area...draped from the northern coastal plain to
Ocracoke. The front is prognosticated to lift towards the Albemarle Sound
today as a trough of low pressure develops along the coastal
plain...and upper ridge builds across the southeast US. Areas of fog
possible this morning...but widespread development will hinge on
amount of high clouds trying to move into the area from the northwest. Hot
and unstable airmass today with isolated/scattered convection
expected...though with limited upper level support will keep probability of precipitation
around 20-30 percent with best chances along the seabreeze...stalled
frontal boundary and inland trough. Although little shear...an
isolated strong to possibly severe storm will be possible with
gusty winds. Increasing low level thickness values and 850mb temperatures
around 18c support highs in the low/middle 90s inland...and 85-90 degree
along the coast. Hot temperatures combined with dewpoints in the
upper 60s to middle 70s will result in heat index values around 100
degrees this afternoon.

&&

Short term /tonight/...
as of 3 am Thursday...the weak front is prognosticated to continue to lift
northward tonight with troughing inland. Will continue SC/chance
probability of precipitation overnight as models continue to show with weak impulses rotating
through the northwest flow aloft. Best chances across the northern tier.
Lows in the low/middle 70s.

&&

Long term /Friday through Wednesday/...
as of 230 am Thursday...no signif changes to forecast with bouts of rain showers/thunderstorms and rain
expected Friday through Sat as cold front slowly pushes S through the region
and short waves cross in northwest flow aloft. The highest precipitation chances
appear to be focused over northeastern and eastern portions of the
forecast area where strongest upper forcing will coincide with best
low level convergence and deeper moisture. For now will have high
chance probability of precipitation for eastern areas for most of this time frame with
slight to low chances to the SW. Severe thunderstorm chances appear to be
limited by marginal instability but directional shear may support
some weakly rotating storms Friday afternoon. Heavy downpours again
a threat especially with the peak in precipitable water Friday
afternoon and evening. With front slow to cross Friday will again be
hot with 90 to 95 expected inland and 85 to 90 beaches. As NE flow
develops in wake of front Sat will see temperatures hold in the 80s poss
approaching 90 far S.

Surface front drives south along the southeast coast Sunday and stalls well
south of the area early next week. A drier northwest upper flow and surface
high pressure to the NE building down the middle Atlantic coast should lead
to reduced precipitation chances Sunday into Monday, so have lowered probability of precipitation
to slight chance and mainly for inland areas to coincide with
favorable diurnal cycles. Atypical onshore flow for August will lead
to slightly below normal maximum temperatures Sunday/Monday...mainly low to middle
80s.

Later in the long term forecast period...model consensus suggests a
building of the Midwest upper ridge toward the East Coast. This should
lead to a mostly dry period...however with persistent onshore flow
highs will remain in the 80s.

&&

Aviation /07z Thursday through Monday/...
short term /through tonight/...
as of 3 am Thursday...patchy fog beginning to develop across the
area...and with little overall change to atmosphere from last
night expect fog and stratus development again with IFR or below
conditions likely...however if high clouds increase and/or showers
do develop that could hinder fog development. Any fog/stratus that
develops should mix out by 14z...with mainly VFR conditions
returning with isolated to scattered convection.

Long term /Friday through Monday/...
as of 230 am Thursday... bouts of rain showers and thunderstorms and rain expected Friday through Sat
with short waves moving across in northwest flow aloft. There will likely
be some brief periods of reduced ceilings/visibilities when rain showers/thunderstorms and rain cross
otherwise mostly VFR expected. Precipitation covering expected to diminish
Sunday and Monday as high pressure and a little drier air pushes in from
the north...shld be mainly VFR.

&&

Marine...
short term /through tonight/...
as of 3 am Thursday...latest observation show southeast/SW winds around 5kt with seas
2-3ft. Weak front draped through the Pamlico Sound and central
waters will continue to slowly lift northward today...and likely
linger near the Albemarle Sound region...before pushing north of
the area tonight. Little change to forecast today with southeast/SW winds
5-10kt. Gradient will tighten overnight with S/SW winds increasing
to 5-15kt.

Long term /Friday through Monday/...
as of 230 am Thursday...cold front will slowly push S across the waters Friday
afternoon through Sat morning. Winds will be quite light over the area as the
front crosses Friday and Friday night...then shld see NE winds increase to
10 to 15 kts Sat afternoon...highest north. Seas will be 2 to 3 feet through Sat
morning then may see some 4 footers outer northern waters late Sat. NE winds
will increase to 15 to 20 kts Sat night and sun as gradient tightens
with high pressure building S over the inland areas. As winds increase
seas will build to 3 to 5 feet...poss reaching 6 feet outer northern waters
late sun. Some uncertainty for Monday as could have a tropopause system well
to the S per models. With high continue just to the west and poss low to the
S will continue to see decent NE winds with seas of 4 to 6 feet Monday.

&&

Mhx watches/warnings/advisories...
NC...none.
Marine...none.

&&

$$
Synopsis...cqd/rf
near term...cqd
short term...cqd
long term...btc/rf
aviation...rf/cqd
marine...rf/cqd

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