245
FXUS62 KMHX 222349
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
749 PM EDT Wed May 22 2024

.SYNOPSIS...
High pressure shifts offshore today. A broad frontal zone then
moves slowly through the Eastern U.S Thursday through the
weekend. A stronger cold front moves through early next week.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 1900 Wednesday...No major changes to the forecast in the
near term. Seabreeze has just about pushed through the entire FA
approaching I95. Have tried to hone in on fog potential in the
early morning hours THU. Best chance for impactful fog over the
HWY17 corridor with patchy shallow fog possible elsewhere across
the area.

Previous Disco...

- Reduced risk of dense fog tonight

The afternoon seabreeze has developed and is slowly shifting
inland. Thus far, the cumulus field has remained fairly flat
along the advancing seabreeze, likely due to warming temps aloft
and mid/upper level ridging in place. In light of this, I
expect the seabreeze to remain quiet through the evening hours.

In the wake of the seabreeze passage, light winds and a moist
boundary layer may support some patchy, shallow fog. However,
the risk of dense fog appears much lower tonight. Case in point,
probabilistic guidance only gives a 20-40% chance for the area
at large.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
As of 115 PM Wednesday...

- Building heat on Thursday

- Strong thunderstorms possible (10-30% chance) across the
  coastal plain Thursday afternoon and evening

Mid/upper level ridging will shift offshore on Thursday as an
upper level trough approaches from the west. This will open up
the Gulf of Mexico, allowing a plume of 1.50" PWATs to get
pulled north through the Southeast US on the ensuing southerly
LLJ. Low-mid level moistening along this frontal boundary, plus
modest lift from a glancing shortwave, should support bands of
convection developing from the southern Appalachians northeast
through the Mid-Atlantic Thursday afternoon into Thursday
evening. As the clusters of storms approach the coast, they will
be encountering the diurnally- stabilizing airmass, and I
expect this will lead to a weakening trend with time with any
storms that approach coastal ENC. That said, if thunderstorms
manage to develop early enough out to our west, there may be a
window of opportunity for thunderstorms to reach the far inland
coastal plain counties, mainly with a gusty/damaging wind
threat. Given decent synoptic and model support for a low-end
severe risk, I`ll add a mention in the HWO with this forecast
update, which will line up closely with where SPC has outlooked
a "Marginal" risk of severe weather. Additionally, heating of
the moistening boundary layer may lead to sufficient weakening
of the cap for a few storms to develop along the seabreeze.
Later Thursday evening into Thursday night, showers may make it
to the coast, but the risk of thunderstorms is expected to be on
the decrease with time.

Warming low-level thicknesses plus strong heating and a
continued southerly flow should allow inland areas to reach the
upper 80s to low 90s, with heat indices as high as 95. Along the
coast, upper 70s to mid 80s will be common. Widespread clouds
and a modest southerly wind will support a very mild night
Thursday, with lows only falling to near 70.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
As of 3 PM Wednesday...An incoming upper level trough will
support unsettled weather through the period with a series of
shortwaves forecast to move across the area. This will bring
multiple opportunities for showers and thunderstorms.

Friday - Tuesday...With high pressure offshore and broad
troughing across the eastern US, southwesterly flow will have
ENC within a warm and humid airmass. Multiple shortwaves passing
over the area will support a chance of showers (25-45%) and
thunderstorms each day. Ensemble guidance shows multiple chances
over the coming days for sufficient CAPE and shear, which could
generate some strong to severe storms, especially in the
afternoon and evening.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
SHORT TERM /through 00Z Friday/...
As of 1920 Wednesday...Seabreeze has cleared inland TAF sites
with VFR flight cats prevailing through the rest of this
evening. Thinking remains mostly the same for fog potential
overnight tonight; potential exists but confidence is lower than
previous nights. Moist low- levels plus light winds tonight may
support a period of sub-VFR VIS. Best chance coastal terminals.
Have slightly walked back the TAFs for the coastal sites a
little bit: changed prevailing MVFR BR lines to 6SM MIFG with a
tempo group with 4sm MVFR BR. Because winds are not expected to
fully decouple all night, think the fog will be very spotty in
coverage and will be transient with OBS likely bouncing around a
bit. VFR flight cats with strengthening SWerly flow through the
day Thursday before flight conditions begin to deteriorate
tomorrow evening when showers/tstorms become possible.

LONG TERM /Thursday night through Monday/...
As of 3 PM Wednesday...Pred VFR conditions are expected through
most of Thursday. The weather will become more unsettled on
Friday and continue through the weekend with multiple rounds of
showers and thunderstorms possible. Periods of sub-VFR
visibilities and ceilings are expected.

&&

.MARINE...
SHORT TERM /through Thursday night/...
As of 115 PM Wednesday...

- Good boating conditions through Thursday afternoon

High pressure will continue to shift further away from the
coast today, with a developing southerly background wind of
5-15kt. This flow will increase some late Thursday into Thursday
night as a weak frontal boundary approaches from the west. At
this time, though, winds are expected to remain below 25kt. Seas
will hold in the 2-3 ft range through Thursday morning, then
slowly build to 3-4 ft late Thursday into Thursday night.
Thursday evening, a weakening cluster of showers and
thunderstorms may impact area waters. A few gusts of 25kt+ may
occur with these showers/storms.

LONG TERM /Friday through Monday/...
As of 3 AM Wednesday...SW winds of 10-15 kt with gusts to 15-20
kt, as well as 2-3 ft seas and multiple chances for showers and
thunderstorms, will stick around through the period.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...None.

&&

$$
SYNOPSIS...MHX
NEAR TERM...RM/CEB
SHORT TERM...RM
LONG TERM...OJC
AVIATION...CEB/OJC
MARINE...RM/OJC