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770
FXUS62 KILM 150718
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
318 AM EDT Wed May 15 2024

.SYNOPSIS...
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Strong to severe thunderstorms may develop this afternoon into
this evening ahead of a cold front that will drop in from the
north. High pressure should bring dry weather Thursday with
pleasant temperatures. Rain chances will increase again this
weekend as a new storm system advances eastward. Drier and
warmer weather should develop next week.
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&&

.NEAR TERM /THROUGH TONIGHT/...
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The mid level trough and associated pressure systems
will open up today and push eastward quickly. Expect good coverage of
showers and thunderstorms again today in what appears to be three
stages. All of the rounds or stages are capable of producing severe
weather and SPC has elevated the risk to slight. However the second
and third stages later this afternoon and again this evening seem
more supportive for deeper convection and severe reports.

Initial convection should readily develop later this morning in and
around Cape Fear but may be limited by instability and minimal
shear. The big boys develop later this afternoon a bit more to the
west via good surface heating and the arrival of higher shear values
and high resolution guidance is showing several updraft helicity
swaths. Finally the third area should occur in the far northwest
areas with similar favorable conditions in the very late afternoon
and early evening hours. Overall active day expected with the
primary threats of strong wind gusts and hail.
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&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
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Vertically aligned low pressure off the Mid Atlantic coast
Thursday morning should very slowly drift eastward and out to
sea late this week. Northerly winds on the west side of this low
should push a wall of low clouds southward across the eastern
Carolinas Thursday morning which might take several hours to
burn off after sunrise. Mostly sunny skies should eventually
develop with daytime cumulus held shallow by a subsidence
inversion developing between 6k-10kft. Forecast highs are
generally in the lower 80s

Weak surface high pressure will settle across the area Thursday
night. Mainly clear skies should allow temperatures to fall into
the lower 60s for most areas away from the beaches. The high
should push offshore Friday morning with southerly winds
establishing a connection to the Gulf during the afternoon and
evening hours. The subsidence inversion should erode as the
upper ridge pushes off to the east, and scattered showers will
become possible inland during the afternoon. Activity may spread
down to the coast Friday night but should remain scattered,
awaiting the arrival of better shortwave energy Saturday.
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&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
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Models still display surprising diversity in timing with this
weekend`s storm system. The upper trough axis for example is
shown at 12z Saturday over Missouri and Arkansas in the GFS. The
00z ECMWF run valid at the same time shows this feature
hundreds of miles farther east across eastern Kentucky and
Tennessee. The Canadian is in between these extremes. Both the
GFS and Canadian operational runs are consistent with their own
ensemble means which makes it difficult to profess either are
really outliers. The 00z ECMWF ensemble mean is not yet
available as I`m writing -- but the 00z ECMWF operational run
is significantly faster/farther east than its 18z ensemble
mean. This doesn`t inspire confidence in the ECMWF this run.

While all models suggest Saturday should see the best
coverage of showers and thunderstorms, the large model spread
leads to increased uncertainty concerning rain chances
lingering into Sunday. Forecast PoPs increasing to 60-80
percent Saturday afternoon ramp down to around 30 percent
Sunday, then down to only 20 percent Monday as there`s higher
likelihood that a cold front will have swept through by then
bringing drier air in from the north. Mainly dry weather is
expected by Tuesday with warming temperatures as upper ridging
should build across the eastern U.S.
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&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
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MVFR to IFR conditions expected through the overnight hours as
light winds and plenty of low level moisture are in place.
Improvement will occur mid morning or so as some breaks in cloud
cover are expected. IFR expected late tonight and into Thursday
morning via similar conditions.

Extended Outlook...Periodic flight restrictions are possible
early Wed evening from thunderstorm activity. VFR conditions to
dominate Thu through Fri. The next system with potential flight
restrictions will affect the area this weekend.
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&&

.MARINE...
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Through Tonight...Wind speeds on the way down this morning and
overall should settle into a southwest flow of 10-15 knots with a
brief uptick perhaps this evening. A weak offshore develops early
Thursday. Higher residual seas warrant continuation of the small
craft advisory through the morning hours with lower seas this
afternoon and overnight.

Thursday through Sunday...Light offshore winds are expected
Thursday in the wake of low pressure moving farther off the Mid
Atlantic coast. A weak ridge of high pressure will spread
across the Carolinas Thursday night into Friday morning with
light and variable winds expected. Winds should become southerly
during the day Friday as the high moves offshore.

Attention will then shift to low pressure across Arkansas that
will move into southern Missouri by Saturday. Gulf moisture
lifted northward ahead of this system should lead to showers and
thunderstorms becoming quite widespread in coverage Saturday.
The storm system will develop a new low pressure center over
Virginia on Sunday. This should help push a cold front across
our area Sunday night with the chances for showers and thunderstorms
continuing.
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&&

.TIDES/COASTAL FLOODING...
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Other - Rip Currents: Yesterday`s strong onshore winds have abated,
however a 4 foot southerly swell every 8 seconds continues to crash
onshore. South-facing beaches on Brunswick County and extreme
northeasterly Horry County run orthogonal to this swell and will
have the largest potential of rip current activity today.
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&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...High Risk for Rip Currents from 6 AM EDT this morning through this
     evening for NCZ110.
SC...High Risk for Rip Currents from 6 AM EDT this morning through this
     evening for SCZ054.
MARINE...Small Craft Advisory until 9 AM EDT this morning for AMZ250-
     252-254-256.

&&

$$

SYNOPSIS...TRA
NEAR TERM...SHK
SHORT TERM...TRA
LONG TERM...TRA
AVIATION...SHK
MARINE...TRA/SHK
TIDES/COASTAL FLOODING...TRA