Area forecast discussion
National Weather Service Newport/Morehead City NC
623 am EDT Tuesday may 21 2013
Synopsis...
high pressure will continue offshore through Wednesday. A cold front
will approach the area Thursday and cross the region Friday. High
pressure will follow the front for the upcoming weekend.
&&
Near term /today/...
as of 615 am Tuesday...weak trf aloft easy to see on radar with cells west of
rdu moving southeast and activity to the east lifting NE. The weak upper trf
will drift east today and slowly weaken. Models continue to show axis of deep
moisture with precipitation water at or above 1.75 inches across the region. Continue
trend of higher probability of precipitation inland today with lower probability of precipitation near CST as inland
moving sea breeze will lead to less activity for the beaches this afternoon.
Modest instability and weak shear will limit severe threat but some locally
heavy downpours likely. Shld have enough sun for highs 80 to 85
inland and around 80 beaches.
&&
Short term /tonight/...
as of 3 am Tuesday...with limited forcing and diminishing instability
expect convection to end quickly this evening. Most of the region
will be dry overnight however did add slight pop imd CST later as
most models show some light quantitative precipitation forecast developing with the moist srly flow.
Lows will be mainly 65 to 70 once again.
&&
Long term /Wednesday through Monday/...
as of 315 am Tuesday...warm/moist southerly flow will continue
Wednesday/Thursday as eastern NC remains located between ridge offshore
and a broad trough over the midwestern states. Maintained slight
chance/isolated probability of precipitation inland for showers and weak thunderstorms
Wednesday. Focus shifts to the southern coast/coastal waters Wednesday evening
then all of eastern NC as weak shortwave energy approaches from
the SW with good agreement among medium range models on quantitative precipitation forecast along
and east of Highway 17. Temperatures Wednesday and Wednesday night remain a few degrees
above normal...middle 80s inland to middle 70s obx.
An upper trough will approach from the west Wednesday night acting to
push the upper ridge over the western Atlantic farther out to
sea. The upper trough will drag a cold front through eastern NC
Friday. SW flow persists Thursday with precipitation chances remaining 30-40
percent. Trended probability of precipitation down for inland portions early Friday as
trough moves off the coast. Temperatures will be near climatology Thursday and Friday
with temperatures in the low 80s inland to middle 70s obx. Return to dry
conditions Friday night with the front off the coast...winds shifting
northwest then north and weak cold air advection initiating across the region.
The upper trough will dig south through NC/Virginia Friday night with high
pressure building over the region from the north through Sat. Weak
cold air advection will persist Sat and sun with broad upper troughing aloft and
weak ridge at the surface...yielding NE surface flow over the
area with temperatures in the low 70s along the coast to middle/upper 70s
inland...below climatology for late may. Shortwave energy will rotate
east-southeast around the base of the upper trough Monday and interact with a
weak backdoor front to produce some showers across the region Monday.
Have added slight chance probability of precipitation for this feature Monday. Temperatures remain
mild Monday with highs in the 70s.
&&
Aviation /10z Tuesday through Saturday/...
short term /today and tonight/...
as of 615 am Tuesday...patchy low clouds and fog early with local MVFR/IFR
mainly deep inland where there is also a threat of a rain showers. Later
today mainly VFR with brief/local reduced ceilings/visibilities in scattered
convection. Precipitation shld end this evening with mainly VFR rest of the
night...however again cant rule out some late night patchy fog or
lower ceilings as low levels remain moist.
Long term Wednesday through Saturday/...
as of 315 am Tuesday...mostly VFR conditions for terminals Wednesday and
Thursday as eastern NC remains in moist SW flow. Aviation conditions
could deteriorate to MVFR and possibly IFR Thursday night into Friday in
lowered ceilings/visibilities associated with a cold front crossing the
region from the northwest. Return to VFR expected Sat as the front pushes
well offshore and winds shift north.
&&
Marine...
short term /today and tonight/...
as of 615 am Tuesday...high pressure offshore will maintain south-southwest winds at
mainly 10 to 15 kts. May see a period of 15 to 20 kts this afternoon and
evening over the central and northern waters. Buoys show seas are currently 3
to 4 feet and are expected to stay in that range through tonight.
Long term /Wed through Saturday/...
as of 315 am Tuesday...SW gradient will persist over the NC coastal
waters Wednesday through Friday between high pressure offshore and a trough
approaching from the west. Winds will range 10-20 knots with seas
mostly 3-5 feet. The gradient pinches slightly tighter Thursday
afternoon and may need an Small Craft Advisory for seas of 6-7 feet for the central
and northern waters. Scas likely Thursday night into Friday as the cold
front nears and crosses the waters...with seas generally 2-4 feet
nearshore to 4-7 feet near the outer fringes of the coastal waters.
Had issues with local Swan/nwps with this forecast package so
manually adjusted 00z wavewatch iii for seas 1-2 feet higher than
guidance across the northern waters Sat once cold air advection surge and north to NE
winds begin impacting the region.
&&
Mhx watches/warnings/advisories...
NC...none.
Marine...none.
&&
$$
Synopsis...rf
near term...rf
short term...rf
long term...dag
aviation...rf/dag
marine...rf/dag
