923
FXUS62 KILM 141345
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
945 AM EDT Sun Jul 14 2024

.SYNOPSIS...
A heat wave will begin today and last into midweek. Afternoon
thunderstorms will be more localized and scattered in coverage
until a front reaches down into the Carolinas and stalls late
Wednesday through Friday, increasing rain chances and
hampering the dangerous heat.

&&

.UPDATE...
No major changes with the latest update, although did bump up
peak heat indices to closer to 110 degrees this aftn in spots,
mainly near the coast where dewpoints should be greatest just
before the sea breeze passes and brings lower temps. However,
most spots should see several hours of heat indices of 105 to
109 degrees. No significant severe storm risk with the main
concern locally heavy rainfall due to high moisture levels and
weak steering flows.

&&

.NEAR TERM /THROUGH TONIGHT/...
Elongated Bermuda ridging sfc and aloft will get suppressed
south of the area this period resulting in westerly flow aloft.
This will produce a downslope trajectory off the Appalachians
along with compressional heating and drying out the atm column
somewhat. Unfortunately at the sfc, this means warmer/hotter
temps across the FA today with WSW winds backing to the S this
aftn and evening. This will help compromise any lower dewpoints
that try to mix down from aloft. When you combine the 90+ degree
temps and dewpoints in the 70s to lower 80s, that spells heat
indices AOA 105 degrees. Thus, a Heat Adv has been issued for
the entire ILM CWA, including the immediate coast, with the
hours 11am thru 7 pm highlighted. Mesoscale boundaries such as
the sea breeze and inland sfc trof, will provide basically the
only forcing avbl for tstorms to develop given the lack of any
s/w trofs aloft in the vicinity. POPs generally kept in the low
chance this aftn and evening with various MOS guidance keeping
it altogether out of the fcst. Tonight will feature any
dissipating convective debris clouds early on followed by
mainly clear skies. Fog and/or low stratus inland may become an
issue if winds decouple aided by any rainfall from the days
convection. Widespread 70s to near 80 at the coast for tonights
lows.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
The heat will peak during this period and combine with high
humidity to produce Heat Warning conditions Mon and possibly
into Tuesday. Temps will rise into the mid 90s across much of
the area on Mon and Tues, but Mon will see some places in the
upper 90s. Overall, a hot and humid period as ridge stretches
across much of the south with heights above 590 Dec and 850
temps peaking around 21c on Monday.

Diurnal convection should be limited both Mon and Tues mainly
due to local effects as Piedmont trough dominates inland and
sea breeze and southwesterly flow around Bermuda High lead to
convergence and lift. Therefore will maintain chc of rain in the
scattered range but should die off each evening as the sun sets
and heating dies down. Should see a few places getting a chance
of a good shot of rain but overall plenty of sunshine with some
aftn cu development on Mon. Tues could see more in the way of
clouds, especially mid to high clouds as a minor perturbation
in the upper level flow may ride across the Southeast allowing
debris clouds to make it into the area.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Although ridge tries to build in from the east, a broad mid to
upper trough begins to dig down from the Great Lakes towards the
Gulf coast and it becomes more amplified as ridge builds up
across the Desert Southwest. This will weaken the ridging over
us and this trough aloft will push a cold front and Piedmont
trough east and south with increasing moist southerly flow
across the Carolinas that will enhance convective development
especially Thurs and Fri. Pcp water values will reach back up
near 2.4 inches Wed through Fri.

A very warm and moist air mass will remain in place and
potential for heat advisory conditions will continue on Wed, but
by Thurs and Fri temps will be modified by clouds and increase
of shower activity and storms and lowering of heights. Have
continued to lower pops a bit through most of the period with
highest values on Thurs.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
VFR to dominate this period however enough threat of tstorms
along an inland progressive sea breeze will continue to warrant
VCTS for all terminals. Still contemplating in upgrading to
POP30 for this potential convection. Will see a cu field at
periodic ceilings of 3500-5000 ft from mid to late morning thru
the day. Winds generally SW-W 5 kt or less this morning
becoming S 10-15 kt across the coastal terminals by midday as
the sea breeze develops and pushes inland, reaching FLO/LBT mid
to late aftn. Could observe periodic MVFR/IFR ceilings and/or
vsby from fog and/or low stratus late tonight, mainly during the
pre-dawn Mon hrs.

Extended Outlook... High pressure will bring the return of a more
typical summertime pattern with diurnally driven convection with
brief restrictions possible daily. VFR should otherwise dominate
outside of any early morning fog/low cigs. By Thu, a cold front
will drop into the Carolinas accompanied by more organized
convection with an increase in coverage.

&&

.MARINE...
Through Tonight...Stalled frontal boundary across the Central
Carolinas will morph into a sfc trof this morning and persist
into next week. Bermuda high pressure will ridge south of the
waters to Fl during this period. The ILM Coastal waters will lie
between the 2 resulting in southwesterly winds at 10-15 kt thru
the period, except around 15 kt with g20 kt nearshore possible
this aftn and evening due to the sea breeze development and push
inland. Seas will run 2 to 4 ft and dominated by a SE swell at
8+ second periods. Short period wind waves, especially this
aftn/evening, will keep significant seas closer to 4 ft.
Possible isolated convection nearshore aided by forcing from the
sea breeze.

Monday through Thursday... Bermuda High will dominate the
weather through much of the week with S-SW winds. Winds should
remain in the 10 to 15 kt range with higher gusts in aftn sea
breeze and influence of Piedmont trough through Tues but a cold
front approaching late Wed into Thurs should push winds up to 15
to 20 kts. A longer period SE swell around 2 ft and 8 to 9
seconds will mix in.

&&

.TIDES/COASTAL FLOODING...
Other - Rip Currents: High risk of rip currents will be lowered
to moderate today as SE swell lowers a bit, down to 2 ft and
high tide will occur during middle of the afternoon.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Heat Advisory until 7 PM EDT this evening for NCZ087-096-099-
     105>110.
SC...Heat Advisory until 7 PM EDT this evening for SCZ017-023-024-
     032-033-039-054>056-058-059.
MARINE...None.

&&

$$

SYNOPSIS...RGZ
UPDATE...RJB
NEAR TERM...DCH
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...DCH
MARINE...DCH/RGZ
TIDES/COASTAL FLOODING...