659
FXUS62 KILM 132009
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
409 PM EDT Mon May 13 2024

.SYNOPSIS...
High pressure will move offshore today, allowing Gulf moisture
to spread northward. Widespread showers should develop late
tonight and be joined by thunderstorms and areas of heavy rain
on Tuesday morning as a warm front lifts through. Scattered
showers and storms will remain possible through Wednesday, but
dry weather is expected on Thursday as high pressure builds in.
More rain chances could develop on Friday as the next storm
system approaches.

&&

.NEAR TERM /THROUGH TUESDAY/...
Ejecting shortwave over the southeastern US will bring deep
moisture overnight. Increasing moisture and isentropic lift will
bring widespread showers by Tuesday morning, increasing in
intensity throughout the day. Periods of heavy rain are
possible, especially during the afternoon along the coast. Weak
instability may fuel a few isolated thunderstorms. Strong shear
and low level helicity could produce a tornado in the strongest
of these storms. Thick cloud cover will keep temperatures in the
upper 70s. Inland on the west side of the low, temperatures may
peak in the mid 70s. Showers become scattered during the late
afternoon as dry air filters in behind the exiting low.

Rainfall totals have decreased since the latest forecast
update. Models continue to waiver in how uniform precipitation
will be as it shifts north and east on Tuesday. Still, periods
of heavy rain area expected which could make travel difficult
for a brief period.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
On the backside of the lead shortwave responsible for the
widespread shower activity on Tuesday, weak shortwave ridging
and the loss of any daytime heating should result in a relative
lull in shower activity during Tuesday evening. With another
impulse following close behind it and nocturnal cooling acting
to reduce instability, some guidance suggests a decaying line of
showers and thunderstorms may arrive in the western zones
around midnight and continue dissipating as it tracks across the
Pee Dee region. Whether or not this occurs, forcing provided by
the impulse should result in at least isolated to widely
scattered showers and storms during the overnight hours before a
cold front pushes through on Wednesday morning, especially with
pwats remaining 1 to 2 standard deviations above normal until
the frontal passage occurs. Overnight lows will remain quite
mild ahead of the cold front, with mid-upper 60s forecast.

On Wednesday, with the closed mid-level low and several
vorticity lobes rotating about it tracking eastward, this will
bring the potential for at least a couple waves of showers and
thunderstorms across the area, especially during the afternoon
and evening. Weak to moderate instability and modest but
sufficient effective shear remains evident on forecast
soundings, keeping at least a marginal risk (threat level 1 out
of 5) for severe weather in play, with the main threats being
large hail and damaging winds. High temperatures should reach
the low-mid 80s with mixed clouds and sun as cooler temperatures
aloft help to develop plenty of cumulus. Showers and storms
should dissipate late on Wednesday with the loss of daytime
heating. With passage of the mid-level low aloft, another cold
front is expected to slide through from the north, veering winds
to NNW overnight. Low temps will depend on how much cool
advection happens behind the front, with low-mid 60s presently
expected.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Mid-level ridging and surface high pressure will make for a dry
and pleasant Thursday into Friday morning with daytime highs in
the low-mid 80s and overnight lows in the low-mid 60s.

Dry weather will be short-lived as another upper system
approaches from the west and brings unsettled weather over the
weekend. Guidance continues to show some differences in the
timing and evolution of the mid-level features, which has
resulted in keeping PoPs in the chance range across the area for
this update. Temperatures are expected to stay above normal,
but of course these will be modulated by the extent of cloud
cover and showers. The storm system should move offshore by
Sunday with weak high pressure building in behind it for the
start of next week.

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
Low level Cu will increase this afternoon in onshore flow. A
few brief showers are possible, but restrictions are not
expected (brief MVFR if any occur). High clouds increase
overnight with lowering ceilings through Tuesday morning. MVFR
conditions are expected everywhere after midnight with showers
increasing from south to north through sunrise. A few areas of
IFR are possible inland near sunrise, but confidence is low in
the warm advective regime in holding on to a solid IFR
restriction through Tuesday. More likely to be a variation of
VFR/MVFR/IFR in periods of heavy rain through late Tuesday.

Extended Outlook...Flight restrictions may occur Monday night
into Tuesday with the next weather system moving in. Improving
conditions into Thursday. Another system approaches the area for
next weekend.

&&

.MARINE...
Through Tuesday...
Onshore flow will increase tonight ahead of a developing low. SE
winds turn southerly by Tuesday morning and winds increase to
15-20 knots with gusts up to 30 knots at times. The existing
Small Craft Advisory has been extended to all nearshore waters
through early Wednesday, primarily for 4-7 foot seas. Showers
and thunderstorms on Tuesday could bring a strong wind gust or
isolated waterspout.

Tuesday night through Saturday...
SCA conditions due to seas are expected to continue through
Tuesday night while isolated to scattered showers and
thunderstorms continue ahead of a cold front. The cold front
will push offshore on Wednesday, however, unsettled weather
conditions due to additional showers and storms may linger into
Wednesday evening before high pressure finally builds across
the Carolinas for Thursday into Friday. Another storm system may
bring unsettled weather for late Friday through Saturday, but
winds and seas are currently expected to stay below SCA
thresholds.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...None.
SC...None.
MARINE...Small Craft Advisory from 11 AM Tuesday to 9 AM EDT Wednesday
     for AMZ250-252-254-256.

&&

$$

SYNOPSIS...ILM
NEAR TERM...21
SHORT TERM...ABW
LONG TERM...ABW
AVIATION...21
MARINE...21/ABW