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000
FXUS62 KILM 181850
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
250 PM EDT Tue Jul 18 2017

.SYNOPSIS...
Shower and storm coverage will decrease in the days ahead
as a front dissipates and drying aloft takes place. A strong
ridge of high pressure will bring the hottest temperatures of
the summer season late week and weekend, and heat advisories
and even warnings may be needed.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
As of 300 PM Tuesday...Isolated to widely scattered showers and
thunderstorms are expected through the evening before losing their
luster with the loss of heating. A mid/upper low across central NC
has already displaced the deepest band of moisture farther offshore
per water vapor imagery. The mid/upper low will slowly meander
across eastern NC over the next 12-36 hours and bring a drier column
to the forecast area. Still enough instability and lingering
moisture warrants mainly diurnal isolated to widely scattered
convection during Wednesday. Wednesday`s max temperatures will
rebound from the cloud limited and rain-cooled high temperatures
observed today across a large part of the forecast area. However,
even warmer temperatures are expected beyond the near term period as
the focus shifts from heavy rain producing convection to heat index
concerns. Otherwise, could see some fog develop overnight,
especially across those areas that received recent rainfall.


&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 300 PM Tuesday...Unusual summertime cutoff upper low will
drift right overhead at around 06Z Thursday as it sinks southward.
Thursday afternoon and night it then turns west and retrogrades into
Savannah, feeling the influence of a large anticyclone covering most
of the south-central U.S. Unsettled weather had preceded this
feature while we were on its eastern side but we now spend the short
term forecast period under the subsidence associated with its exit,
which will lead to negative differential vorticity advection and
height rises. Most of the period thus appears rain-free save for the
possibility of very isolated thunderstorm activity along the
seabreeze during peak heating Thursday afternoon. This is suggested
by the GFS and SREF but not the WRF. The current forecast of 20 POPS
along the coast looks reasonable. Thursday highs will be a few
degrees above climatology while lows will remain slightly elevated
both nights.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 300 PM Tuesday...Initially mid level low pressure will be wobbling
westward along the Gulf Coast undercutting a potent ridge centered
along the Mississippi Valley. This area or Col in meteorological
parlance will keep convection to a minimum via mid level capping
although this time of year it can never be ruled out. I suspect as
we move forward in time small pertubations may show up in the weak
circulation thus increasing pops albeit slightly. The pattern
becomes more conducive for convection in time and this is reflected
in the later parts of the forecast. Guidance has trended a little
lower on overall temperatures especially the ECMWF but still expect
most of the period to see temperatures somewhat above normal.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
As of 18Z...MVFR conditions are possible in/near any widely
scattered showers and tstms through the afternoon period along with
a few left over strato-cumulus decks from earlier storms. Potential
for MVFR VSBYs will increase overnight, especially at KILM, KFLO,
and KLBT. VFR conditions expected to prevail after 13Z Wednesday
with less coverage of convection during the day

Extended Outlook...Flight restrictions are not foreseen at this
time.

&&

.MARINE...
NEAR TERM /THROUGH WEDNESDAY/...
As of 300 PM Tuesday...A weak trough along the coastal waters and
earlier convection has helped to skew the local wind field. Overall
the flow is expected to become briefly southwest by the evening then
veer to an light offshore direction during the early morning hours.
A sea breeze circulation will turn the flow back around to a
southerly direction during Wednesday. Speeds around 10 knots through
the period outside any convection. Seas will average 2 to 3 ft
through the period.

SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 300 PM Tuesday...Very light SW winds and just 2 ft seas
through most of the period. An upper low will somewhat disrupt the
normal 10-15kt/2-3 ft forecast usually borne of the Bermuda high
this time of year. 15kt winds may represent a few gusts but will
generally not make it into the forecast and seas will remain capped
at 2 ft. A minor uptick in winds/seas may be noted Thursday night as
the upper feature retrogrades south and west.

LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 300 PM Tuesday...Expect southwest winds of 10-15 knots for the
duration. There will inevitably be some nocturnal acceleration
from time to time but this amount of detail is all but
impossible to put into the extended. Significant seas will be
2-4 feet.

&&

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

&&

$$
SYNOPSIS...SHK
NEAR TERM...SRP
SHORT TERM...MBB
LONG TERM...SHK
AVIATION...SRP