382
FXUS62 KRAH 291458
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
1057 AM EDT Sat Jun 29 2024

.SYNOPSIS...
A potentially dangerous hot and humid air mass will become
established across the area this weekend. A cold front will approach
the area Sunday bringing a chance of thunderstorms Sunday afternoon
and evening. A much more seasonable air mass will arrive with a
Great Lakes high pressure Monday and Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1057 AM Saturday...

Water vapor imagery this morning depicted a de-amplified ridge over
the southeast. Further upstream, a developing trough and associated
convection was evident over the Midwest/Great Lakes region. A weak,
convectively-enhanced short-wave currently over Missouri/Illinois
will progress east across the mid-Atlantic today.

The remotely-sensed MMIC-TPW satellite product depicted a pocket of
residual drier air over much of central NC this morning. This drier
air will lift northeast and offshore today, as flow turns more sly
with increasing PWAT expected to stream in from the west late
tonight. Void of upper forcing (shunted to the north), and strong
sfc forcing, showers/storm coverage should be limited and primarily
confined to the higher terrain today. A few showers and isolated
storms could trickle into the far western Piedmont this afternoon,
and perhaps a rogue sea-breeze cell further east, but overall it
should be mostly dry today.

Given the persistent sly flow today, temperatures should once again
reach the mid 90s.  However, given the exiting residual drier air,
think that the dew points could mix out a bit more than previously
thought later this afternoon (upper 60s).  As such, heat indices may
not officially reach Heat Advisory criteria, but should hover in the
100 to 105 range.  Given that these values will be quite close to
advisory criteria, and that the experimental HeatRisk product
depicts the "Major" category over much of central NC, will let the
current Heat Advisory ride this morning.

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
As of 333 AM Saturday...

The heat and humidity peak, but with good chance of thunderstorms to
bring cooling relief late day and Sunday night.

High heat and humidity will be the rule of the day at least until
scattered thunderstorms begin to develop in the early to mid
afternoon. Heat indices may very well be higher Sunday than today if
the clouds/storms hold off until mid to late day (which appears the
case for the eastern areas). Temperatures will get an early start
given the lows expected to be near 80 at many locations. Actual
highs in the lower to mid 90s are expected, with heat indices
possibly 105-109 from Raleigh and Durham south and east through the
Coastal Plain and Sandhills. Heat indices may top out near 100 in
the normally cooler NW Piedmont region before the chance of storms.

Given the high heat and humidity, instability MLCapes 2000-2500 J/kg
should result increasing the chance of strong to locally severe
storms. However, the stronger flow aloft is generally limited this
far south and southwest. SPC has placed at least the NE quad of our
region in a slight risk, with a marginal risk over the rest of
central NC. The primary threat will be local damaging wind.

Showers and thunderstorms are likely Sunday evening, especially from
the Triangle Area south and east. Hopefully, this will bring some
cooling rain for areas that have had little rainfall in the past
month. It will be cooler Sunday night after the front and hopefully
rain pass the region. Lows in the mid 60s to lower 70s expected.

&&

.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 /12Z SATURDAY THROUGH WEDNESDAY/...
As of 645 AM Saturday...

IFR stratus is likely to develop at all terminals through 13z-14z.

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

Outlook: Sub VFR conditions will be possible Sunday morning with IFR
stratus, followed by a chance of mainly afternoon and evening
thunderstorms Sunday.

VFR conditions are expected early to mid week next week.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 2 PM this afternoon to 8 PM EDT Sunday for
NCZ024>028-040>043-076>078-088-089.

&&

$$

SYNOPSIS...Badgett
NEAR TERM...Luchetti
SHORT TERM...Badgett
LONG TERM...KCP
AVIATION...Badgett