Area Forecast Discussion
Issued by NWS Wilmington, NC-- Highlight Changed Discussion --
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FXUS62 KILM 281346
Area Forecast Discussion
National Weather Service Wilmington NC
946 AM EDT Tue Mar 28 2017
-- Changed Discussion --The risk for showers and an isolated strong thunderstorm will
occur this afternoon ahead of a cold front which will move
through late tonight. Relatively cooler and drier high pressure
will build in from the north late Wednesday into Thursday.
Showers and thunderstorms are expected as warmer and more humid
air returns Friday ahead of a cold front which will move
offshore early Saturday. Some of the thunderstorms may be strong
to severe Friday and Friday night. The weekend should be dry as
high pressure takes hold. Then early next week, a southern
stream system will again bring the risk for showers and
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.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --As of 945 AM Tuesday...Convection is occurring ahead of a short
wave this morning over Bladen and Columbus counties and this
will continue to shift off the coast. For the afternoon and
second short-wave trough will push across the area with the best
chances over southeast North Carolina and Darlington, Dillon.
The morning soundings are showing surface base CAPES of 1200 to
1400 J/kg with wet-bulb zero ranging between 9000 ft in the
north and 11000 ft to the south. With partial clearing for the
afternoon this may help enhance a chance of thunderstorms to
develop again tonight.
Southerly winds will veer slowly to the SW and become gusty
through the day before shifting to the W by Tues evening as
trough moves through. Expect plenty of clouds through the day
but some breaks or brightening will allow temps to reach up
toward 80 most places. The increasing SW flow will fight against
inland movement of sea breeze and therefore the stable air
behind sea breeze will remain pinned closer to the coast.
Overall expect increasing westerly flow aloft and drier air to
put an end to convection across the area by late aftn with some
lingering clouds into the evening. Pcp water values up around
1.4 inches in the aftn will drop under an inch by midnight as
winds from the sfc up through the mid levels become westerly and
eventually northwest overnight. Clearing should take place
overnight although some residual low level moisture will remain
into the morning. Temperatures will drop off slowly as the cold
front will not actually make it through until the early morning
hours on Wed. Low temps should be in the mid 50s most places.
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.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 300 AM Tuesday...Cold front will be offshore Wed morning.
Strong high pressure centered across eastern Canada will begin
to ridge south across the Carolinas later Wed and Wed night. A
wedge will develop Wed night and persist into Thu before the
ridge begins to weaken and shift offshore Thu night. Dry weather
Wed into Thu as partial sunshine returns. A potent southern
stream system will approach from the W Thu night. Clouds will be
on the increase later Thu and especially Thu night. The system
has slowed down some, but will continue to advertise a slight
chance/small chance of showers and thunderstorms, mainly
overnight Thu with the lowest risk across the Cape Fear area and
the highest across the I-95 corridor and westward.
The cool air Will be slow to arrive and so highs on Wed should
still be well above normal, upper 70s to lower 80s with marine
influences keeping the coastal communities in the lower to mid
70s. Highs Thu will be in the upper 60s to lower 70s with
perhaps some mid 70s across portions of the Pee Dee. Lows will
be mainly in the 50s.
.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 300 AM Tuesday...Next in series of potent southern stream
systems will impact the eastern Carolinas Fri and Fri night with
a categorical risk for showers and thunderstorms developing.
The combination of significant upper level support and strong
and deep moisture return and lift provides at least the
opportunity for a more widespread and significant rainfall
event. There will be some risk for strong to severe
thunderstorms during this time. 0-6 km effective bulk shear
parameters are not particularly impressive. However, instability
does grow with mixed layer CAPE values on the order of 500 to
1000 J/kg as the warm front should move to our N. Mid-level
lapse rates are forecast to be rather modest. The potential is
there for an active day/night leading into the weekend, although
magnitude is certainly still a question mark.
In the wake of this system, dry weather and near to above
normal temps are expected for the weekend as mid-level ridging
builds across the area and surface high pressure builds from the
NW and N. Attention then will turn westward as next southern
stream system along the Gulf Coast Sun night lifts to the NE and
drags a warm front to the N. This will again bring deep
moisture into the Carolinas, and with that, showers and
thunderstorms early next week. Given timing differences between
long range models and a general slower trend as compared to 24
hours ago, will cap POPs in the chance category until we can
gain better resolution as to when the highest risk for showers
and thunderstorms will occur.
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
As of 12Z...The greatest coverage of showers and some thunderstorms
will move across portions of the I-95 corridor through 14-15z.
The highest probability for a thunderstorm at any of the
terminals this morning will be KLBT. The convection will be in
the vicinity of KFLO, but the brunt should pass just to the N
this morning. Conditions will be VFR throughout, except there is
the potential for visibility to briefly drop to MVFR in rain at
any terminal. The most organized convection will be ahead of a
shortwave this morning through midday with any activity this
Winds will veer slowly through the day, but may see a slight
backing along coastal terminals in the afternoon due to the sea
breeze. Sustained wind speeds will be up to 10 to 15 kt today.
A cold front will push through late tonight, shifting winds to
the NW and N toward morning. Did not include any restrictions
in fog overnight, but later forecasts may as the dry air will be
slow to advect across the area.
Extended outlook...Flight restrictions are likely in showers
and thunderstorms Fri/Fri night and thunderstorms may contain
strong wind gusts.
-- Changed Discussion --NEAR TERM /THROUGH TONIGHT/...
As of 1000 AM Tuesday...SW
SW winds 10 to 15 kt continue at Frying Pan Shoals and 10 knots
at the piers. Winds will increase as the pressure gradient
tightens as the cold front approaches from overnight. Seas will
increase to 3 to 5 feet north of Little River and 2 to 4 feet to
A longer period SE swell will continue to reach our local waters
from a rather deep low pressure system well offshore from the SE
U.S. Coast forecast to move northeast, further away from the U.S.
mainland. Boaters navigating to and from area inlets on Tue could
encounter rough wave conditions especially during an outgoing tide
combined with the incoming 10+ second period swell.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 300 AM Tuesday...Cold front should be offshore at the
start of the period. Strong high pressure across eastern Canada
will build south and eventually wedge across the Carolinas Wed
night and Thu. The strong ridge should then move offshore Thu
night. N winds Wed morning will veer to NE. NE winds Wed night
and Thu will then veer to SE Thu night. Sustained wind speeds
will increase to 15 to 20 kt Wed night and remain in that range
through the end of the forecast period. Seas will build to 3 to
5 ft by Wed night and then remain in that range for much of Thu
before perhaps subsiding about a foot Thu night.
LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 300 AM Tuesday...A Small Craft Advisory is likely for all
waters Fri and Fri night with conditions possibly lingering
Slow moving area of low pressure will be moving across the Ohio
Valley Fri. Its accompanying warm front will move across the
waters Fri. As low pressure moves offshore of the Mid-Atlantic
states late Fri night and Sat morning, it will strengthen and
drag a cold front across the waters. High pressure will slowly
build across the area from the N and NW Sat night and Sun.
SE winds Fri morning will become S and then SW Fri night. The
wind direction will become westerly early Sat morning and then
NW by Sat afternoon. N winds Sat night will become NE overnight
Sat with NE winds persisting into Sun before veering to easterly
during the afternoon.
The strongest winds are expected Fri and Fri night, up to 20 to
25 kt. Seas late Fri and Fri night will build to 4 to 7 ft and
around 8 ft at frying Pan Shoals. Seas during Sat will only slowly
subside as backswell from departing storm system impacts the
waters. Seas should drop below advisory levels by late Sat and
to 2 to 4 ft on Sun.
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