Area NWS Forecast Discussion
000
FXUS62 KILM 200524
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
124 AM EDT Mon Aug 20 2018

.SYNOPSIS...
High pressure offshore will maintain warm and humid weather,
with a chance of showers and thunderstorms through the period.
A cold front is expected to cross the coast Wednesday night,
with a drying trend Thursday into early next weekend.

&&

.NEAR TERM /THROUGH TODAY/...
As of 700 PM Sunday...Main convective activity running from
near Maxton east to Lumberton area and across to Elizabethtown
this evening. Storms were producing a decent amount of mainly
cloud to cloud lightning and some rainfall amounts over an inch
in isolated spots. Other lighter pcp from previous convection
was over southern Georgetown and Williamsburg counties. Plenty
of debris clouds over much of the area except right along the
Cape Fear coast. Otherwise, another warm and humid night on tap
with some limited shwr/tstm activity overnight, mainly closer to
the coast. The mid to high clouds and nocturnal jetting should
help to keep any widespread fog at bay, but in may see some
right around daybreak for a few hours in places that have had
some previous pcp overnight and where skies clear some. Temps
should drop into the mid 70s most places.

Previous discussion:Thunderstorms will develop and be isolated
to scattered this afternoon and tend to focus along areas away
from the coast. Satellite imagery showing deeper cumulus cells
supportive of this idea portrayed by higher resolution guidance
such as HRRR, RAP, and 12Z WRF. GFS solution showing heavier and
further east activity an outlier and was not factored much into
the forecast. Several sheared out vorticity centers will streak
overhead tonight making a dry forecast difficult to go with.
Thunderstorm coverage may increase slightly tomorrow afternoon
with northwestern zones being favored in coverage.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
As of 3 PM Sunday...H5 low approaching the Midwest Monday evening
will deamplify as it lifts across the Great Lakes region during
Tuesday. The mid/upper ridge across the Carolinas will shift
offshore during this time. By Tuesday night the weakening H5 trough
axis will shift across the Eastern U.S. with the bulk of the
dynamics to stay well north of here as it moves by. Ultimately, the
inland trough and sea breeze will provide some lift in an unstable
atmosphere through the short term period with 20-40% POPs fairly
common. Favored a blend of MAV/MET temperatures each period. A
resultant sea breeze will keep conditions breezy along the coast
Tuesday afternoon into the evening.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 3 PM Sunday...Mid-level pattern will be marked by 5h trough
through Fri before weak 5h ridge expands east over the area. Lack of
deep moisture will limit precip chances somewhat during the period,
the best chances likely being Wed as the arriving trough pushes a
cold front into the area. Surface high building in ensures the
front and deeper moisture shift a little farther offshore into
the weekend. At this point uncertainty creeps in concerning how
quickly a weak coastal trough develops and then moves onshore as
the high to the north shifts east. Will continue to carry
chance pop Wed with chance to likely pop Wed night. Once the
front is through, confidence in the forecast decrease and will
carry slight chance to chance pop for the remainder of the
period. Given the lack widespread deep moisture think diurnal
activity will be limited along the sea breeze and any lingering
boundaries. Temperatures start off above climo but following the
passage of the cold front later Wed temps drop below climo for
Thu through Sun.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
As of 06Z...Once again similar conditions expected regarding
the evolution of showers and thunderstorms for the mostly
daytime period. Expect mainly VFR conditions as the coverage
should once again be limited. As for the next few hours, fairly
strong signals that LBT and FLO will see at least a brief period
of IFR fog and or stratus and used tempo groups to address.


Extended Outlook...Scattered showers and
thunderstorms each afternoon and evening, accompanied by brief
MVFR conditions. Cold front late in the period Thursday may
cross all terminals of SE NC and NE SC, bringing a surface wind-
shift.

&&

.MARINE...
NEAR TERM /THROUGH MONDAY/...
As of 700 PM Sunday...SW flow to continue as the area remains
between inland trough and offshore high. The SCEC-worthy 5 ft
seas are no longer showing up in much data; even 41013 is only
running 3.5 ft so this headline has been dropped in favor of a
continuation of a 2-4 ft forecast.

SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 3 PM Sunday...A front is progged to remain north of the
waters Monday night with high pressure far off the Southeast
U.S. coast and a trough located to the west. This pattern will
maintain southwesterly flow across the adjacent waters while the
gradient will keep speeds up to around 15 knots into Tuesday.
The pressure gradient will increase by Tuesday night with a
brief period of Small Craft conditions possible. Seas will be
around 3-4 ft Monday night and Tuesday then around 5 ft during
Tuesday night with steep conditions.

LONG TERM /WEDNESDAY THROUGH FRIDAY/...
As of 3 PM Sunday...Cold front crosses the water later Wed or
Wed night with high pressure building in for Thu and Fri. Ahead
of the front southwest flow will briefly run a solid 15 kt
before veering from southwest to northwest Wed night. Pinched
gradient Thu morning leads to slightly increased northeast flow,
an event that will be repeated late Thu night as secondary
northeast surge sets up. Second round Thu night will be
stronger with solid 15 kt winds possible. Seas 3 to 5 ft at the
start of the period gradually fall to 3 to 4 ft late Wed and Wed
night and 2 to 3 ft Thu and Fri.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.

&&

$$
SYNOPSIS...
NEAR TERM...MBB/RGZ
SHORT TERM...SRP
LONG TERM...III
AVIATION...SHK
MARINE...

NWS ILM Office Area Forecast Discussion