590
FXUS62 KRAH 120725
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
325 AM EDT Wed Jun 12 2024

.SYNOPSIS...
Weak high pressure over the Ohio River Valley will drift east and
move off the coast by Thursday morning. A hot and humid air
mass will develop over the region on Thursday and especially
Friday before a cold front brings some cooler temperatures for
the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 255 AM Wednesday...

The latest surface analysis shows surface high pressure centered
over PA and NY early this morning with a light north to
northeasterly flow across central NC. The airmass across central NC
is rather dry with PW values of around an inch which is about 60-70%
of normal. Further aloft, a northwest flow at mid levels will weaken
and become more westerly and even southwesterly today and
tonight as a short wave trough moves into the Deep South. It
should remain dry today with a mix of clouds and sunshine.
Expect patches of cirrus clouds to move across the region along
with some afternoon stratocumulus clouds, especially across the
western Piedmont where low level moisture is a bit more
prominent. The airmass moderates just touch today across the
south but more noticeable warming should be noticed across the
north and northwest including the Triad where low level
thickness values warm a good 8 to 12m. This will result in highs
similar to Tuesday or maybe a degree or so warmer across the
southern/southeastern areas with highs about 3 to 4 degrees
warmer across the north. Highs should range in the mid 80s in
the VA border counties and Triad area with highs of 85 to 90
elsewhere including the Triangle and Fayetteville areas. Lows
tonight will be a little milder and a touch muggier with lows
mainly in the mid 60s. -Blaes


&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
As of 320 AM Wednesday...

A stationary frontal zone extending from northern FL and far southern
GA to off the Carolina coast will linger through Thursday night.
Several weak areas of low pressure that have developed in part by
convective clusters near and along the front will persist and
advance northeast and will be supported by an approaching short wave
trough. Guidance has perked up a bit with this system suggesting
some sort of low pressure area may develop late Thursday night
or into Friday as the system moves away from the eastern
Carolinas. At the same time, surface high pressure across the
mid-Atlantic will shift east and off the coast by Thursday. The
air mass across much of central NC warms on Thursday as low
level moisture values increase, making it feel warmer and more
humid. Will keep a dry forecast in place with central NC in
between the frontal zone and surface low off the Carolina coast
and an approaching cold front in the Great Lakes and western OH
Valley. Highs on Thursday will be warm, ranging in the upper 80s
to around 90 with some lower 90s across the Sandhills and
southern areas. These highs are about 2 to 6 degrees above
average. Lows on Thursday night will range in the mid 60s which
is a few degrees above average. -Blaes
&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 325 PM Tuesday...

Largely dry weather is expected through this period, with a roller
coaster of temps: hot, then seasonably cool, then above normal again.

Thu/Thu night: The surface frontal zone and any offshore low along
the front will be well to our SE and S, with surface high pressure
centered over the NW Atlantic nosing SW through central NC. Aloft,
very weak/baggy shortwave troughing over NC (as the westerlies hold
well to our N) will give way to rising heights as the ridge over
AZ/NM and N Mex begins to build eastward. We`ll be within a fairly
low PW environment with no opportunity for moisture transport into
the area and increasing stability aloft, so will keep a dry
forecast. Low level thicknesses are just a bit above normal, but
with abundant sunshine (clouds should be limited to sct high-based
flat cu with deep mixing), highs will be near a category above
normal, upper 80s to lower 90s. Lows in the 60s.

Fri through Sat night: A profound shortwave trough will swing
through the Great Lakes, St Lawrence Valley, and Northeast Fri
through Sat morning, which will drive a corresponding surface cold
front SSE through NC late Fri night through Sat morning. The NBM and
LREF members suggest that our extreme SE could see an afternoon
storm Sat near the front if it slows its progression, and have kept
an isolated thunderstorm risk in the far SE Sat, but even this may
be too high. Fri will be another hot day with above normal
thicknesses and narrowing and weakening surface ridging across the
area plus weak NW flow aloft still limiting prefrontal moisture
transport. Once again, clouds both days should be restricted to a
few high-based afternoon cu and perhaps a few wispy high clouds.
Highs will be in the low-mid 90s across the board, with warm lows
Fri night in the upper 60s to lower 70s, pushing our HeatRisk into
the Moderate category over much of the forecast area, indicating a
health threat for sensitive and vulnerable individuals. The Moderate
HeatRisk shifts to just our southern sections Sat, where highs will
be in the low-mid 90s, versus the upper 80s/near 90 across the N
where the cooler air post-front will arrive earlier. Lows will be
back into the 60s Sat night as less humid and cooler high pressure
builds in from the N.

Sun-Tue: Continued dry with temps rebounding back above normal. The
surface high pressure will shift off the Northeast and Mid Atlantic
coast Sun and continue to drift E through Tue while extending back
across NC. Gradually increasing onshore flow in the low levels from
the E and SE will bring increasing clouds, mainly across the S and
W, heading into early next week, with a risk of upslope-assisted
precip by the time we get to Tue. Will have dry weather through
early Tue, then just a slight chance in the W Tue afternoon. Expect
highs in the mid 80s to lower 90s Sun/Mon, then upper 80s-mid 90s
Tue. -GIH

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
As of 245 AM Wednesday...

VFR conditions are generally expected to continue across central NC
for the 24 hour TAF period as a westerly flow aloft and surface high
pressure moves across the region. There is a limited threat of some
patchy low stratus early Thursday morning across southern and
eastern areas but confidence in this developing is limited.
Otherwise areas of VFR stratocumulus is expected to continue and
redevelop across the area with CIGS of 5-8kft along with some
patches of cirrus clouds. Light mainly northeasterly winds early
today will become south or southeasterly at 5 to 10kts.

Outlook: Generally fair weather is expected through the rest of the
work week into the weekend. Some patchy late night/early morning fog
or stratus is possible into the first part of the weekend. -Blaes

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Blaes
NEAR TERM...Blaes
SHORT TERM...Blaes
LONG TERM...Hartfield
AVIATION...Blaes