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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 201135
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
735 AM EDT Thu Jun 20 2019

.SYNOPSIS...
Severe thunderstorms possible ahead of an approaching cold
front this afternoon into this evening. After the cold frontal
passage, drier and less humid air will arrive Friday. Heat and
humidity, and the chance for showers and thunderstorms will
gradually return through the weekend into early next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 320 AM Thursday...`Hot and Breezy, Turning Turbulent`, could
be one headline describing today, ahead of and through,
passage of a squall feature tonight, 23z(7p)-03z(11p) from west
of I-95, to the coast respectively.

Trends have remained consistent in depicting a weakening trend
of said line, from west to east, nonetheless, the SPC raising
the stakes with `enhanced` to `slight` risks from west to east
tonight. The awaiting atmosphere primed with thermal energy,
CAPE around 2500 J/jg and elevated effective shear, should
solidify the line into the I-95 corridor prior to nightfall.

Hazards/Probabilities: Damaging TSTM wind gusts 15-30% highest
inland, 1 inch Hail 5-15%, Tornado 2%.

Max-Ts hot today, because partial downslope trajectory to pin
the sea breeze relatively tight near the coast, should result
in 90s for the Myrtles, and middle 90s over most of SE NC and
interior portions of NE SC.

Pronounced mid level drying and downslope W-NW winds Friday in
wake of the front with no cold air advection of note, will bring
another very warm day above normal, mostly low 90s, and right up
to the ICW.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 300 AM Thursday...Mid to upper ridge extending up through
the Mississippi River will maintain a deep NW flow as it creeps
slowly eastward through Saturday. Weak disturbances in NW flow
aloft will enhance convection along lingering front as it shifts
back northward through Saturday night. Models differ with
location of showers and thunderstorms, but should mainly occur
later on Saturday into Sat night associated with lingering
boundary and sea breeze front, with possible MCS type feature
diving southeast through the Carolinas. Pcp water values closer
to an inch Fri eve will shoot back up closer to 2 inches by late
Saturday in a more unstable air mass. Overall, expect dry
weather to start Fri eve into Sat, with increasing clouds Sat
aftn and potential for showers and thunderstorms mainly late
into Sat night. Temps overnight Fri will drop into the 60s in a
drier air mass, but increasing dewpoints through Saturday will
keep overnight lows closer to 70 Sat night. Highs on Sat will be
between 85 and 90 most places.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 300 AM Thursday...Lingering and weakening boundary at the
sfc will reach back north Sun into Mon with a southerly return
flow developing through early next week. At the same time, ridge
aloft will shift eastward with axis running up through the
Southeast. The influence of any perturbations riding down in NW
flow aloft will diminish heading into early next week. Overall
expect warmer and more humid air mass to settle in with
downslope flow and rising heights contributing to temps reaching
into the 90s. May see heat index values flirting with 100.
Increased subsidence and dry air aloft should allow for only
localized shwrs/tstms through much of the period as low level
moisture remains present. May see front make it into area by
Tues night into Wed if ridge slips east far enough.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
As of 12Z...SCT stratus will break over the next few hours and so
too will any flight restrictions that remain in place. A mostly
clear day with VFR Cu developing in the afternoon. Southerly winds
15-25 knots with higher gusts increasing throughout the afternoon as
the PG tightens ahead of an approaching cold front. With the
existing instability and high shear, high confidence of an
organized line of convection developing this afternoon and
progressing through the CWA, beginning at the inland terminals
around 21Z and reaching the coastal terminals, quickly, by 00Z. LLWS
(25040KT) possible along the coast as the cold front moves through
after 00Z. Clearing skies will follow as winds become westerly
around 10 knots; VFR conditions will return through the end of the
period.

Extended Outlook...Mainly VFR through the period with brief MVFR/IFR
conditions from afternoon convection and early morning fog and/or,
low stratus.

&&

.MARINE...
As of 320 AM Thursday...`Increasingly Treacherous` could be one
headline to describe upcoming marine trends, as a cold front
approaches then smacks the coast, delivering a line of strong
TSTMs over the 0-20 nm water late this evening. Severe storms
are possible over the waters tonight and radar updates are
recommended if you must venture out. Outside of TSTMs, advisory
SW winds expected through tonight, with gusty W winds into
early Friday, not a good time to challenge the Gulf Stream in a
small craft.

Ocean spectrum entirely commanded by SSW waves 5-8 feet every
6-7 seconds, dangerously steep. Imagine winds and seas higher
in and near TSTMs layered on top of this, between 10pm-1am
tonight, clearly hazardous. The waves to peak tonight, waning
Friday, with offshore wind, surfs up, but a deceptive shoaling
hazard ongoing for small craft inshore, in seemingly protected
waters from wind.

Cold front will lose its drive south, getting held up over SC
waters into early Sat. Winds will weaken with off shore flow to
the north of front and a light on shore flow to the south.
Overall expect seas to continue to drop through Fri night down
below 3 ft by Fri night. Flow becomes very weak and shifts
slowly around to on shore to SE Sat night into Sun as weak
return flow sets up through early next week. Overall expect
benign winds and seas after Fri with sea breeze creating a
slight spike in winds and seas each aftn into early eve.
Potential for scattered showers and thunderstorms will exist
through the period. Seas will basically be below 3 ft through
the period with a longer period, 9 to 10 sec SE swell mixing in
early next week.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...Beach Hazards Statement through this evening for SCZ054-056.
NC...Beach Hazards Statement through this evening for NCZ106-108.
MARINE...Small Craft Advisory until noon EDT Friday for AMZ250-252-254-
     256.

&&

$$

SYNOPSIS...CRM
NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...21