418
FXUS62 KILM 300749
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
349 AM EDT Tue Apr 30 2024

.SYNOPSIS...
High pressure will linger offshore today. An upper level
disturbance and weak surface boundary will bring showers and
thunderstorms to the area tonight into Wednesday. High pressure
will return Thursday with a second front bringing more showers
and thunderstorms over the weekend and potentially into early
next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Dry, quiet weather comes to an end later this afternoon and
tonight as weak, southern stream shortwave moving across the
deep south brings scattered convection to the area. Initially
moisture is lacking and there is a bit of lingering mid-level
subsidence in the wake of the exiting ridge. This will help
limit convection and keep the region dry well into the
afternoon. Southerly flow and a fair amount of sunshine,
filtered through high cloud, will once again produce afternoon
temperatures a little above climo.

Vertical profile becomes more favorable for deeper convection
late afternoon into evening as heights start to fall ahead of
the shortwave and moisture starts to increase. Deep moisture
moves in after 00Z and precipitable water jumps from AOB 1" all
day to over 1.6" later tonight. Surface based instability will
be decreasing by the time conditions aloft become favorable, but
lingering low level instability and a weak surface trough help
kick off some evening convection. Storms are likely to persist
well past midnight given the favorable mid-level environment.
Coverage is likely to be limited by the marginal environment and
the nocturnal timing, but still expect 30-50% coverage area
wide. Not much of a low level jet, there is minimal shear and
the boundary layer becomes stable by late evening. Thus no real
strong/severe storm threat. Do expect rumbles of thunder and
some localized moderate to heavy rain. Lows will run above
around 10 degrees above climo.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Potent shortwave aloft tries to close itself off from the main
flow Wednesday, though it may not get there. Regardless, ample
forcing combined with decent moisture brings scattered showers
and thunderstorms to the area, particularly in the afternoon.
Instability and bulk shear parameters suggest a few storms could
carry gusty winds and small hail, especially if SBCAPE values
clock in at 1000 J/kg. In spite of this, mid-level lapse rates
are lackluster, and parcels won`t be as buoyant as they could
be, so this should limit the severe chances. Convection starts
to calm after sunset with loss of daytime heating, and with the
shortwave pushing offshore.

Mid-level ridging builds aloft Thursday through Thursday night,
with the Carolinas caught in dirty-looking Omega blocking
pattern. Precipitable water values drop below an inch, and with
the forcing from the previous day gone, this looks like a dry
forecast. Highs Wednesday in the lower 80s, upper 70s at the
coast. Highs should be a few degrees warmer Thursday, due to
ample sunshine. Lows each night in the low-to-mid 60s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Ridge starts to fall over Friday, with another shortwave
approaching from the west, though this one is much weaker and
more subtle. Dry forecast prevails Friday and Friday night, with
highs in the mid 80s inland, near 80 at the coast. Lows in the
low-to-mid 60s.

A cold front is still slated to approach the area this weekend,
potentially stalling out overhead, due to lack of upper
forcing. Regardless, multiple shortwaves embedded in the zonal
or quasi- zonal flow will work with the surface front to produce
scattered showers and storms throughout the weekend into
Monday. Chances may actually be a bit higher inland, depending
on where the stalled front sets up. Highs still continue to be
in the mid 80s, with lows in the low- to-mid 60s.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
VFR will continue into the evening before MVFR/IFR potential
starts to increase, mainly inland. Southerly flow continues
today with speeds 7-10kt and potential for gusts as high as
20kt associated with the sea breeze. Scattered showers and
thunderstorms will move in from the west this evening and should
continue beyond 06Z. Current timing only has inland terminals
being affected through 06Z.

Extended Outlook...VFR will dominate. Periods of showers and
thunderstorms possible at all terminals late Tuesday night
through Wednesday evening.

&&

.MARINE...
Through Tonight...Bermuda High maintains southerly flow over
the waters with nearshore enhancement in the afternoon and
evening due to the sea breeze. Expect nearshore winds to be a
bit stronger than the last few days as influence of surface
trough and mid-level wave help tighten the gradient. Speeds will
still be well short of advisory criteria with only isolated
gusts to 20 kt very close to shore. Seas 2 to 3 ft today with
widespread 3 ft tonight. Seas continue to be a mix of a
southerly wind wave and a southeast swell with the wind wave
becoming more dominant.

Wednesday through Saturday...SSW winds at 5-10kts continue
through Wednesday, before veering northerly Wednesday night,
then northeasterly Thursday morning, before finally settling on
ESE by Thursday evening. Seas initially at 2-3ft, but decrease
to 1-2ft throughout this time. Winds gradually become more
southeasterly through the remainder of the period, with seas
continuing at 1-2ft. Long period swells out of the east clock in
at 10-13 seconds at times.

&&

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

&&

$$

SYNOPSIS...ILM
NEAR TERM...III
SHORT TERM...IGB
LONG TERM...IGB
AVIATION...III
MARINE...III/IGB