501
FXUS62 KRAH 290608
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
208 AM EDT Sat Jun 29 2024

.SYNOPSIS...
A hot and more humid air mass will become established across the
area this weekend. A cold front will approach the area Sunday
bringing a chance of storms.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 753 PM Friday...

Evening analysis shows a stalled boundary across northern sections
of SC and arcing into eastern TN. High pressure was situated off the
New England coast. The high will shift off into the north Atlantic,
resulting in a developing southerly flow toward sunrise Sat. With
the more moist flow off the southwest Atlantic, dewpoints will
likely rise overnight after mixing out earlier this afternoon.
Daytime convection along the sea-breeze brought isolated storms
across Sampson Co and the Sandhills. The convection has produced a
well pronounced outflow evident on radar, currently pushing into
Moore, Lee, and Chatham counties. As this outflow continues to track
WNW through the late evening, high-res CAMs such as the HRRR show
spotty isolated activity developing over the western/southern
Piedmont and perhaps over the Triad. Any storm activity should
weaken after midnight with loss of heating and forcing, though
cannot rule out a stray shower over the Triad near daybreak.
Overnight lows should be in the upper 60s to low/mid 70s. Guidance
is hinting at some widespread low stratus and possibly patchy fog
with the onshore flow taking shape overnight into daybreak Sat. This
should lift and dissipate by mid-morning.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 415 PM Friday...

Hot, seasonably humid, with a small chance of showers/storms on the
wrn and ern flanks of cntl NC.

Cntl NC will remain tucked between a couple of sub-tropical to lower
mid-latitude mid-level highs/ridges centered over the srn Plains and
w-cntl Atlantic, respectively. Poleward of this expansive zone of
ridging, a compact mid-level cyclone now over nern MT will become an
open wave trough while pivoting across the nrn Plains and upr MS
Valley through 12Z Sat, then accelerate newd and across the Great
lakes and QC through 12Z Sun. A trailing shortwave perturbation now
over the cntl Canadian Prairies will dig sewd into the upr MS Valley
and upr Great Lakes Sat and then follow a similar path as the first
shortwave trough through Sun. In the intervening swly flow between
these shortwave perturbations and the aforementioned ridges, a
convectively-amplified mid-level trough will move across the OH
Valley and cntl Appalachians Sat and the Middle Atlantic Sat night,
the latter when weak mid-level height falls (10-20 m/12hr) will
glance the srn Middle Atlantic. Weak mid-level lapse rates of less
than 5 C/km will exist over cntl NC on Sat, with a slight increase
to between 5-5.5 C/km, amid the aforementioned weakly falling
heights, Sat night.

At the surface, the remnants of a couple of fronts that have settled
across the South Atlantic states during the past 24 hours will
retreat nwd across the Middle Atlantic, on the wrn periphery of high
pressure over the Atlantic basin. Broad sly flow will result
throughout the South and Middle Atlantic states, while a lee trough
will develop with diurnal heating over the srn Middle Atlantic and
Carolina Foothills/wrn Piedmont. Weak confluence between the
Atlantic high and lee trough will result over the Foothills and wrn
Piedmont. A sea breeze will also retreat inland and across ern and e-
cntl NC through the evening.

While both temperatures and humidity levels will be on the increase
as a result of the return to sly flow and the influence of the
ridging aloft, afternoon/mixed surface dewpoints are likely to
decrease into the upr 60s to around 70 F. Resultant heat index
values, when factoring in high temperatures mostly 92-98 F, are
likely to peak in the 100-105 F range over all but the nrn and nwrn
Piedmont, where upr 90s will be common. Those mixed dewpoints will
also result in a minimum of MLCAPE generally between 500-1000 J/KG
over cntl NC, with slightly higher dewpoints in the lwr 70s, and
MLCAPE between 1000-1500 J/KG, along and west of the Yadkin Valley
and from the the far ern Coastal Plain to the coast. A 20-30 percent
chance of showers/storms will consequently exist along the wrn/ern
flanks of cntl NC. Overall coverage and strength of convection will
be limited by the relative lack of buoyancy and forcing for ascent,
aside from low-level convergence along the sea breeze and into the
lee trough.

After a lingering small chance of showers/storms over the srn/wrn
Piedmont during the evening, it will otherwise be warm and muggy
overnight, with lows 75-80 F.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 205 AM Saturday...

Aloft, a trough will progress eastward through the Northeast and mid-
Atlantic Mon/Mon night, while the mid-level anticyclone sits over
the ARKLATEX. As the trough moves away from the East Coast, the high
will once again build into the region from the west, sitting over
the TN Valley/Deep South Tue and Wed. A series of northern stream
s/w disturbances will track eastward through the northern CONUS Tue
through Fri, with each successive s/w slowly suppressing the high
southward. However, the high should generally remain over the
Southeast US through Fri. At the surface, the cold front should be
through NC Mon morning, with high pressure ridging into the area in
its wake from a high moving eastward through the Great Lakes. As the
high continues eastward through the Northeast and offshore Tue/Tue
night, it will continue ridging southward into central NC. Once the
high moves out over the Atlantic, a lee trough will develop, with
swly flow and the advection of warm, moist air into the area taking
over once again. Temperatures may actually be near to slightly below
normal Mon and Tue, but once the warm advection commences on Wed,
they will quickly rise back above normal Wed and remain above to
well above normal through the end of the week. As for rainfall,
aside from some possible lingering showers/storms in the east on
Mon, the next best chance for appreciable rainfall looks to be Fri
night.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
As of 132 AM Saturday...

IFR stratus is likely to develop at all terminals late tonight/early
Saturday morning.

Any lingering stratus should lift to VFR by late morning/early
afternoon. After which, a few isolated showers/storms could impact
KINT/KGSO this afternoon. However, coverage looks limited and mostly
confined to the mountains.

Outlook: Sub VFR conditions will be possible area wide Sunday
morning with IFR stratus, followed by a good chance of mainly
afternoon-evening showers/storms Sunday. VFR conditions are expected
early to mid week next week.

&&

.CLIMATE...

Record High Temperatures:

June 30:
KFAY: 102/2012

July 4:
KGSO: 98/1970
KRDU: 101/2012
KFAY: 98/2019


Record High Minimum Temperatures:

June 29:
KGSO: 74/2010
KRDU: 78/1914
KFAY: 76/1969

June 30:
KGSO: 74/1936
KRDU: 80/1936
KFAY: 79/1936

July 1:
KRDU: 75/2012
KFAY: 76/1990

July 4:
KGSO: 73/2018
KRDU: 79/1902
KFAY: 78/1913

&&

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

&&

$$
SYNOPSIS...Badgett
NEAR TERM...Kren
SHORT TERM...MWS
LONG TERM...KC
AVIATION...Badgett
CLIMATE...RAH