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064
FXUS62 KMHX 210103
AFDMHX

Area Forecast Discussion
National Weather Service Newport/Morehead City NC
903 PM EDT Thu Jun 20 2024

.SYNOPSIS...
High pressure continues to extend across the Carolinas with weak
coastal troughing just off of the coast in place through
tomorrow. This may bring some showers to the region into the
weekend. A steady increase in heat and humidity is expected over
the next several days with "feels like" temperatures
potentially reaching the triple digits on Sunday. The next
chance for much needed appreciable rain comes early next week
with a frontal passage.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
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As of 900 PM Thu...No changes to previous thinking. Mid-level
ridge remains in place over much of the eastern CONUS this
evening as expansive Atlantic high pressure continues to ridge
west over the Carolinas the past several days. Main difference
in the pattern today is a weak tropical wave just north of the
Bahamas, which is forecast to drift towards and eventually
across the far southeastern coast. Eastern NC won`t feel any
direct impacts from this wave, but it will serve as a source for
deeper moisture to attempt to move into the area over the
weekend.

Another dry and mostly cloudless night is on tap for tonight.
Given the persistent easterly flow, however, low-level moisture
continues to move in under the nocturnal low level inversion
and with a radiational cooling, the set up for some patchy fog
is probable in the pre-dawn hours. Best signal for formation is
west of Highway 17, but shallow low impact fog is possible
anywhere in well sheltered locations. Lows tonight will be
similar to last night, in the low to mid 60s inland and upper
60s to low 70s along the coast.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
As of 345 PM Thu...Coastal trough will gradually sharpen
offshore as aforementioned tropical wave shifts toward coastal
GA/FL in the morning. With the deeper moisture advection, the
trough will provide a focal point for shower develop and likely
a few thunderstorms given ample instability offshore thanks to
warm SSTs. Hi-res guidance continues to favor some of this
activity penetrating inland, mainly along the Crystal Coast and
the Outer Banks from Cape Hatteras south, and maintained
mentionable PoPs for these areas from the previous forecast. A
second round of convection is possible along the sea breeze in
the afternoon. Farther inland, high pressure and subsidence
aloft will stubbornly remain in place maintaining hot and dry
conditions. Here, highs will climb into the low 90s but dew
points will make a run towards the low 60s. Along the coast,
highs settle in the upper 80s but dew points will climb well
into the upper 60s to potentially 70 along the immediate coast.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
As of 315 AM Thursday...

 - Still watching the SW Atlantic

 - Increased risk of heat impacts late-weekend into next week

 - Increased risk of thunderstorms next week

Synoptic Summary: Persistent, and anomalous, ridging aloft over the
Eastern U.S. is forecast to finally break down by this weekend, with
broad troughing continuing into next week. At the SFC, low pressure
is forecast to move across the SW Atlantic and towards the FL/GA
coast on Friday, with coastal troughing developing north through the
coast of the Carolinas. Broad surface troughing is then forecast to
develop across the Eastern U.S. over the weekend, and last into next
week. A front, or two, may attempt to make a run at ENC next
week.

Saturday-Sunday: High pressure shifting further east out into the
Atlantic will allow a warming, and moistening, southerly flow to
develop over the weekend. Despite the increasing moisture, it
doesn`t look like the chance of precip will immediately respond,
mainly due to a lack of better instability. At minimum, though, it
looks like a few showers or storms may develop on the seabreeze both
days. The bigger story over the weekend will be the building heat.
With the southerly flow developing, we`ll lose the "cooler" easterly
flow of late that has helped keep temps and humidity at more
comfortable levels. Both deterministic and ensemble guidance
continue to show a good signal for heat-related impacts, especially
on Sunday, as heat indices ("feels like" temps) reach 100-105
degrees. Sunday could be our first opportunity for heat headlines if
recent trends hold.

Monday-Thursday: Humidity will continue to increase next week with a
continued southerly flow off the Gulf of Mexico and western
Atlantic. With increasing low-level thicknesses, the heat and
humidity combination is expected to lead to a continued risk of heat-
related impacts. The risk of thunderstorms will be increasing during
this time as well, though, which will have a daily impact on where
the greatest risk of dangerous heat will be. Bottom line, there
continues to be a good signal for multiple days of an elevated to
significant heat risk for much of the area.

Regarding the thunderstorm risk, Monday continues to be the day
favored for the highest chance, and is also the next appreciable
chance of wetting rainfall to help offset the recent stretch of dry
weather. Guidance differs on the timing of a couple of fronts that
may attempt to move into the area, which of course factors into
where the greatest coverage of thunderstorms will be. Also of note,
some guidance hint at the remnants of the SW Atlantic wave getting
pulled northeast through the area. If this were to occur, this would
support an increased risk of precip. Lastly, the shear/instability
combo still appears supportive of a marginal severe weather risk on
Monday, and that will be something to watch in the coming days.

&&

.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
SHORT TERM /through Friday/...
As of 620 PM Thu...VFR conditions prevail across all terminals
this evening as offshore high pressure continues to extend over
the Carolinas for yet another day. Diurnal Cu field will
dissipate with loss of heating. Main focus overnight will be for
the potential for patches of radiational fog, primarily along
the coastal plain, where clear skies, calm winds, and increasing
low-level moisture provide a favorable set up. Introduced MVFR
visibilities at PGV and ISO for this risk but can`t rule out
patchy fog occuring just about anywhere.

Friday, increasing clouds and moisture from the south as weak
tropical wave/low, currently just north of the Bahamas, migrates
across the far southeastern coast tomorrow morning. The
increase in moisture will feed an uptick in offshore showers and
a few thunderstorms, which could drift along the immediate
coast tomorrow morning. Afternoon sea breeze circulation could
also spark convection in the early afternoon. Signal right now
keeps any MVFR cigs from penetrating more than a few miles
inland, but can see a low-end risk for EWN/OAJ if moisture
intrudes farther than forecast.

LONG TERM /Thursday night through Tuesday/...
As of 315 AM Thursday...

 - Increased risk of TSRA and sub-VFR conditions Monday

A developing coastal trough may support low CIGs and SHRA/TSRA along
the immediate coast Friday. This will be followed by isolated SHRA
and TSRA developing each day along the seabreeze over the weekend. A
better chance of TSRA and sub-VFR conditions is still expected
Monday. A period of breeze southwesterly winds is expected Sunday
into Monday as well, with non-TSRA gusts of 20-25kt possible.

&&

.MARINE...
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SHORT TERM /through Friday/...
As of 900 PM Thu...No changes to previous thinking. Swell from
a weak tropical wave just north of the Bahamas this evening
continues to encroach into our offshore waters, mainly south of
Cape Hatteras, where seas remain 5-7 feet. High pressure remains
in control with another night of easterly flow around 10-15 kt.
The tropical wave is forecast to drift inland near the FL/GA
border tomorrow morning, and this afternoon`s swell will
gradually abate through the evening. SCAs for the waters south
of Ocracoke Inlet have been extended through the evening, but
all others were previously dropped as waves subsided to 3 to 5
feet.

Another benign day of boating conditions returns tomorrow, with
winds gradually veering more southerly through the day as the
surface high finally begins to move further offshore. Winds will
generally be no higher than 10 kt and seas will be able to
return back to around 4 feet, except 3 feet closer to shore.

LONG TERM /Friday night through Tuesday/...
As of 315 AM Thursday...

 - Elevated wind and seas Monday

 - Increased thunderstorm risk on Monday

Elevated seas from today will begin to slow lay down on Friday as
the persistent easterly flow of late begins to subside. Weaker flow
continues into Saturday, with south winds of 5-15kt common. That
southerly flow will notably increase to 15-25kt Sunday into Monday,
with a subsequent increase in seas to 4-6 ft once again. Sunday and
Monday will present the next chance of SCA conditions. Coastal
troughing developing on Friday now appears more supportive of
scattered showers and thunderstorms, especially for the waters south
of Cape Hatteras. This risk then subsides over the weekend some,
before increasing again as we move into early next week.
-- End Changed Discussion --

&&

.FIRE WEATHER...
As of 4 AM Thur...Minimum RHs will reach 35-40% this afternoon
(primarily away from the coast). Given the continued dry airmass,
dry fuels, and E`rly breezes, these conditions remain noteworthy
for any ongoing, or planned, fires.

&&

.MHX WATCHES/WARNINGS/ADVISORIES...
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NC...Beach Hazards Statement through Friday evening for NCZ195-196-
     199-203>205.
MARINE...Small Craft Advisory until 2 AM EDT Friday for AMZ156-158.
-- End Changed Discussion --

&&

$$
SYNOPSIS...MHX
NEAR TERM...JME/MS
SHORT TERM...MS
LONG TERM...RM
AVIATION...RM/JME/MS
MARINE...RM/JME/MS
FIRE WEATHER...MHX