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551
FXUS62 KILM 261438
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
1038 AM EDT Sun May 26 2024

.SYNOPSIS...
Unseasonably hot and humid conditions are expected to continue
through Monday with isolated to scattered mainly afternoon and
evening thunderstorms. An approaching cold front should enhance
thunderstorm coverage late Monday into Monday night. A cooling
trend and mostly dry weather is expected to commence from
Tuesday onward as the first cold front pushes offshore and a
secondary front arrives early on Thursday. Dry high pressure
should remain in control going into this upcoming weekend.

&&

.UPDATE...
-- Changed Discussion --
Forecast on track for a quiet afternoon with only low end chance
of convection associated with sea breeze and then passing shwr
late evening or after midnight. Plenty of sunshine and warm
temps and fairly calm waters at the beaches.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
Patchy fog has developed across parts of the area, mainly those
locations that received the highest rainfall amounts on Sat. Thus
far the fog has been transient and will continue to do so due to
light boundary layer winds and occasional cloud cover. Fog will be
quickly mix out with most areas seeing fog dissipating within an
hour of sunrise.

Shortwave moving off the coast this morning and brief 5h ridging
building over the area today will limit diurnal convection this
afternoon. Subsidence is weak, suggesting a storm or 2 could develop
along the sea breeze or any additional boundaries. However, the
unfavorable environment, mainly deep dry air, will keep coverage
much less than the last few days. Trended inherited pop down from
chance to slight chance during the afternoon hours, but held onto
chance pop in the evening and first part of the overnight. The
environment becomes a little more supportive of deeper convection
later in the day and this evening. The next 5h disturbance
approaches from the west later today, spreading some weak PVA over
the Piedmont. The wave is accompanied by deeper moisture and
precipitable water jumps from around 1.4" in the afternoon to near
1.9" in the evening. Dry air will be the biggest limiting factor
today, so the increased moisture should translate into more storm
development even if surface based instability is trending down at
that point.

Temperatures above climo continue. Most of the area will see highs
above 90 today with the sea breeze once again struggling to move
inland from the coast. Less afternoon convection and associated
cloud cover compared to last few days may allow for mid 90s at a few
inland hot spots. Cloud cover and increased winds tonight will keep
lows well above climo.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
A weakening squall line originating from the Mid-South should
continue to fall apart before reaching the area on Monday
morning. This will bring considerable mid-upper cloudiness which
should tend to thin and shift east during the afternoon.
Depending on how thick these clouds end up being, high
temperatures on Monday may be impacted, but the high sun angle
and likely translucent nature of these clouds should still allow
highs to reach the low 90s with peak heat indices in the mid-
upper 90s. Otherwise, little convective development is expected
during the afternoon (mainly focused along the sea breeze) as
mid-level dry air and subsidence should keep a lid on
convection until a cold front slides in from the west late in
the day and overnight.

Timing of the cold front`s arrival and the magnitude of
convergence along it will be crucial in determining the severe
weather threat for late Monday into Monday night as moderate to
strong instability and 40-50 kts of effective shear are shown in
forecast soundings during peak heating, which would support a
notable threat if convection is able to develop well-ahead of
the front. However, both of these parameters rapidly decline
during the evening before the front should arrive in our CWA,
thus bringing into question how much severe potential will
actually exist along the front. At this time, a "marginal" risk
for severe weather (threat level 1 out of 5) is outlooked by the
Storm Prediction Center with the main threats being large hail
and damaging winds. Regardless of the severe weather threat,
scattered showers and thunderstorms should accompany the front
as it slows down and stalls near the coast by late in the night.
Low temps should only fall to around 70F with minimal advection
behind the boundary as winds turn westerly.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Any leftover showers or storms near the coast should shift
offshore during Tuesday morning as shortwave energy aloft moves
offshore as well. However, the front should still linger near
the coast through the day, keeping PoPs in the slight chance
range during the afternoon. Highs in the upper 80s to around 90F
will result in large CAPE, which could result in strong pulse
storms near the coast, especially with westerly flow behind the
front helping to enhance convergence along the sea breeze.
Further inland, subsidence and mid-level dry air should preclude
thunderstorm development.

The front should be shoved offshore on Tuesday night as height
falls associated with a shortwave pivoting around broader mid-
level troughing to our north arrive from the northwest. Winds
subsequently turn northwesterly with a more distinct push of
drier air arriving on Wednesday, marking the arrival of a
stretch of dry weather. Another shortwave and further height
falls are expected to arrive on Wednesday night, with cooler and
drier air arriving for Thursday. Guidance seems to agree on the
mid-level trough remaining in place through Friday before
shifting eastward with ridging following in its wake for the
weekend. Temperatures will fall to near- or below- normal late
in the week as troughing dominates. A gradual warming trend will
result if the modeled ridging builds in over the weekend.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
Areas of MVFR fog have developed during the last few hours with
isolated pockets of IFR. These will quickly mix out after
sunrise with VFR at all terminals by 13Z with VFR. Expect to
see a few afternoon storms develop with slightly more coverage
in the evening as activity moves in from the west. Coverage will
be much more limited than past days and the chance for any TAF
site seeing storm impacts is low with best chances at inland
terminals. Lingering cloud from storms tonight and boundary
layers winds 4-7kt will keep fog from being a concern tonight
and there doesn`t appear to be enough moisture in the low levels
for FR stratus.

Extended Outlook...Scattered mainly afternoon and evening
thunderstorms may be accompanied by periodic short lived IFR
conditions Monday and Tuesday.

&&

.MARINE...
Through Tonight...
Pattern remains static over the waters with Bermuda High and
Piedmont trough producing southwest flow with some afternoon and
evening speed enhancement. Storm coverage will be much less today,
although there is still potential for a few storms moving offshore,
especially during the evening hours. Seas around 2 ft today and
tonight with a few areas approaching 3 ft late afternoon/evening due
to enhanced southwest flow. Seas will be a mix of a southwest wind
wave around 4 seconds and a southeast swell around 8 seconds.

Monday through Thursday...
An approaching cold front will result in south-southwesterly
winds at 15-20 kts on Monday veering to southwesterly and
weakening to around 10 kts on Monday night. The front should
stall near the coast and keep winds southwesterly until it
pushes through on Tuesday night, with northwest winds taking
over on Wednesday before becoming variable as the front washes
out. A reinforcing cold front should bring more sustained
northerly winds over Wednesday night which veer to northeasterly
on Thursday.

Seas increase on Monday to 3-4 ft in response to the
approaching front and tightened pressure gradient. As the front
stalls and winds weaken, seas relax to 2-3 ft on Tuesday and to
around 2 ft on Wednesday. The secondary front reinforces a
northerly offshore flow on Thursday, but without a persistent
or strong push, seas are expected to remain benign in the 1-2 ft
range.

&&

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

&&

$$

SYNOPSIS...ILM
UPDATE...RGZ
NEAR TERM...III
SHORT TERM...ABW
LONG TERM...ABW
AVIATION...III
MARINE...III/ABW