922
FXUS62 KILM 090734
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
334 AM EDT Fri May 9 2025

.SYNOPSIS...
Showers and thunderstorms will precede a cold front that will
cross the area later today. Rain will shift south into South
Carolina Saturday before returning northward late in the weekend
into early next week. Rain chances return early next week and
linger through the middle of the week as a system moves into the
area from the Gulf Coast.


&&

.NEAR TERM /THROUGH TONIGHT/...
Convection supported by weak impulses aloft have congregated into a
disorganized mass of showers with embedded thunderstorms. Some of
these storms will sustain a small hail threat prior to sunrise. Weak
instability will decrease as this mass pushes eastward through
sunrise. Remnant showers are likely to be all that remain as the
activity pushes east of the I-95 corridor. Showers push east of I-95
for the morning commute and reach the coast during the mid morning.
Confidence in meaningful shower activity surviving to the coastal
communities of southeastern NC is Low with a better chance southward
and inland. This will be the first round of rain chances today with
a better chance for coastal areas later in the day.

A cold front is currently analyzed to be situated along the TN-KY
border through northern VA. This boundary will drift south and
southeastward today toward the Carolinas. This cold front will form
the leading edge of an upper low that will drop into the Mid
Atlantic late today and tonight.

Warm air advection out of the west and southwest, ahead of the cold
front, will likely push temperatures into the mid 80s today.
Uncertainty exists surrounding clouds and rain this morning. The
bulk of models suggest that sunshine may be hard to find and keep
highs a few degrees lower, but the potential for very warm
temperatures exists today.

Convergence along the sea breeze this afternoon is expected to
produce the main source of afternoon convection. As mentioned
previously, coverage is uncertain due to the previous existence of
remnant showers and clouds. Regardless, a few storms could produce a
strong wind gust or two along the coast as drier air entrains during
the late afternoon especially. Dry air aloft will compete with
surface lift and warm temperatures, but HREF members are consistent
that the focus of the activity will be near the coast with stray
storms inland. This does have some merit as the air mass in the west
and central Carolinas has been worked through its available energy
and deep layer westerly flow generally produces sinking air in the
lee of the southern Appalachians.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Occluded low over eastern New England will have pushed a cold front
off the coast with high pressure and drier air(well compared to the
pre-frontal airmass) spreading in the from the north. May be some
weak subsidence in the wake of the exiting 5h trough Sat, but the
stable low levels and cooler air mass work to keep the bulk of the
region dry Sat. The best rain chances will be closest to the front,
basically the southern-most portion of the forecast area. Even
chances in these areas remain in question and will be determined by
how far south the front sages. Cold advection ends during the
morning, but mostly cloudy skies will help keep highs in the low
70s, at best.

Rain chances increase marginally late Sat and Sat night with
development of weak isentropic lift and coastal trough taking shape.
Boundary layer remains on the dry side, but just above the boundary
layer (which is pretty shallow) there is a deep layer of RH >90%.
Temperatures above normal Sat night. The stalled front starts to
return back north on Sun as a couple surface waves move northeast
along the boundary. The combination of abundant moisture, weak
dynamics with the waves and the occasional weak shortwave will all
lead to an increase in rain chances Sun and Sun night. The weak
nature of the forcing may limit intensity of any rain or embedded
showers, limiting total rainfall amounts. Temperatures Sun will be
similar to Sat. Highs well below normal with lows well above.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Stacked low over the western Gulf Coast Mon morning slowly lifts
north-northeast into the TN Valley Tue and then across the Mid-
Atlantic or the Southeast states Wed into Thu. This will lead to an
extended period of unsettled conditions across the Southeast with
deep southerly flow spreading moisture over the region. Precipitable
water hovers around 150% of normal for much of next week, exceeding
175% of normal Mon into Tue. Plenty of positives that suggest the
first half of next week will be an active weather period.
Convergence along a slow moving warm front(both directional and
speed), decreasing heights at 500 mb, divergent flow aloft(100 kt
jet at 200 mb late Mon and Mon night), and occasional shortwave
ejecting from the 5h low. The environment also suggests potential
for heavy rain with deep warm cloud layer and pwat approaching 2" at
times. Best potential for heavy rain will be Mon into Tue when deep
moisture is at its highest.

Confidence in the long term being an active period weatherwise is
high, but the specific details and timing remain elusive, given the
presence of a cutoff low which always give the guidance fits. There
has been a slowing trend with the 5h low as well as a slight
southerly shift to its movement. Previous solutions had drier air
moving in later Wed and Thu, but a slower, more southerly solutions
would lead to moisture lingering longer. The result would be highs
below normal through Thu instead of a return to normal Wed or Thu.
Lows will be above to well above normal.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
Ongoing convection to our west will merge into a larger mass
and push eastward overnight. Restrictions will reach inland
terminals within the next few hours, possibly down to IFR due to
VIS. As the limited instability remaining is consumed by
existing storms, rain rates will weaken. Expect a brief period
of MVFR VIS restrictions with a few CIGs possible along the
coast early this morning.

The initial wave of precipitation moves offshore this morning.
As a cold front approaches from the north today and mid level
energy encourages lift along a pinned sea breeze, showers and
thunderstorms will again be a possibility. Inland areas should
remain VFR today ahead of the front, a brief period of IFR in
showers and thunderstorms near the coast.

A cold front moves through the region tonight with low clouds
possible behind the surface boundary by Saturday morning.

Extended Outlook... Confidence is low surrounding a stalled
frontal boundary offshore that could bring showers to the coast
on Saturday and Sunday with drier conditions inland. Unsettled
weather returns to much of the area early next week, forecast
confidence is low at this time.

&&

.MARINE...
Through Tonight...

Light westerly flow this morning will turn southerly this
afternoon as a sea breeze develops near the coast. An
approaching cold front will produce isolated convection this
afternoon near the coast. Westerly winds aloft will push this
convection offshore and lightning (and slightly stronger winds
and elevated seas) will be possible near the immediate
coastline. Thunderstorm chances increase late this afternoon and
overnight for the nearshore waters as the cold front pushes
offshore. Winds turn N and NE behind the cold front late tonight
with gusts up to 20-25 knots possible in the initial NE surge.
Seas between 2-3 feet today increase late tonight to 3-5 feet.

Saturday through Tuesday...
Front pushes south of the waters Sat and lingers there into Mon
before a weak coastal trough and the front move across the
waters, setting up easterly flow next week. Low pressure along
the Gulf Coast and surface high to the north tighten the
gradient Mon and Tue, increasing onshore flow. Highest seas will
be later Mon and Tue, once the enhanced onshore flow develops.
Northeast surge Sat will briefly build seas to 4 ft, but 4-6 ft
will be possible Mon night and Tue. An easterly swell will be
the dominant wave with an east or southeast wind wave likely to
develop sometime Mon night or Tue.

&&

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

&&

$$

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