945
FXUS62 KRAH 060629
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
228 AM EDT Thu Jun 6 2024

.SYNOPSIS...
A pre-frontal trough and cold front will move across the area
Thursday evening through early Friday. High pressure will move in
with cooler and drier air for the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 225 AM Thursday...

...There is a Level-1 (Marginal Risk) For Severe Storms this
afternoon and early evening...

...Gusty wind is expected to be the primary hazard with the stronger
storms and isolated storms may reach severe limits...

The mid/upper trough moving through the Great Lakes states will send
a pre-frontal trough through central NC this afternoon and evening.
Central NC will be removed from much influence of the upper trough;
however, strong heating will allow for MLCAPE to reach near 2000
J/kg during peak heating. In addition, a deep W-SW flow and bulk
shear around 20 knots may also aid in organization of storms.

Scattered thunderstorms should form on the pre-frontal trough and
possible evolve into a line of showers/thunderstorms as it moves ESE
across our region. The most likely timing would be around 19z-22z in
the Triad, then 21z-02z in the Triangle and points south and east.
The line of showers/storms will eventually move east of the region
this evening.

The cold front will arrive later tonight, but little if any
showers/storms are expected after the pre-frontal trough sweeps most
of the MLCAPE and moisture out of the region.

Highs today should reach the mid to upper 80s NW ranging into the
lower 90s SE. Lows tonight will be in the 60s.

&&

.SHORT TERM /FRIDAY and FRIDAY NIGHT/...
As of 225 AM Thursday...

...Lowering humidities and temperatures Friday and Friday night...

Mid and upper troughing will be along the eastern seaboard Friday
and Friday night. Central NC will be on the back side of the trough
with the axis moving offshore. CAA will drive the humidities and
even temperatures down from early June standards. With partly to
mostly sunny skies, highs will reach the lower to mid 80s NW ranging
into the mid to upper 80s east and south. Lows will dip into the 55-
60 range except lower 60s SE.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 228 AM Thursday...

A persistent northwest flow is favored to be in place through much
of the extended. Embedded in that flow will be the potential for
disturbances within the larger pattern to influence central NC with
rain chances, most favored in the Sun to Tue period.

Sat will feature high pressure in place across the southern
Appalachians. Models then show a cold front reaching portions of the
lower OH and TN valleys by early Sun. Ahead of that, guidance shows
a thunderstorm complex developing somewhere over the Mid-Mississippi
Valley Sat morning in the return flow over the Midwest. Most of the
deterministic models take this energy into the Carolinas Sat night
ahead of the front. We are fairly stable with little if any
instability, but there could be a non-zero threat of a decaying MCS
reaching the area early Sun.

Sun-Wed: Most guidance brings the front on Sat through late Sun into
early Mon. This would appear to be the best chance of showers and
storms with return flow, PW`s returning above 1.5 inches, and energy
at mid-levels tracking in from the TN valley in the NW flow.
However, there remains uncertainty as most of the GFS/ECMWF/CMC show
the greatest instability across GA/SC. The best chance would be in
the afternoon and evening hours. Sun looks be our warmest day in the
extended with above normal highs in the upper 80s to lower 90s.

Model uncertainty continues to grow Mon into Wed. We still appear to
remain in a NW flow to start the week, potentially transitioning to
some weak ridging by midweek. The cold front in the guidance appears
to reach the Deep South early Mon, with perhaps a reinforcing front
Mon night into Tue, before the Bermuda high takes over into Wed.
Nearly all the deterministic models keep the instability axis well
to our south during this time across the Deep South. GFS point
soundings show a subsidence inversion as well during this period.
However, we will be in the NW flow and ensemble guidance still show
embedded energy in the flow to warrant rain chances. The best
chances appears to be Mon into Tue, though confidence is low given
the overall suppression of deeper moisture and frontal forcing. More
diurnally driven showers/storms could return Wed in a more favorable
return flow. Temperatures should gradually trend upward from below
normal in the low/mid 80s Mon to the mid/upper 80s Wed.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
As of 145 AM Thursday...

24-hour TAF period: Scattered patches of mid and high cloudiness
will stream across central NC, before IFR/MVFR stratus and
stratocumulus again develop late tonight by around 08-10z. The
highest confidence of this occurring is at the Triad terminals (INT
and GSO), followed by RDU and FAY, and lastly RWI. S/SW winds should
stay elevated overnight (around 5-10 kts) and this combined with the
low stratus fog is not expected to be a concern. Conditions
will improve to VFR by mid to late morning, but a line of showers
and thunder storms associated with a pre-frontal trough is
expected to move east through central NC during the afternoon and
evening. The best guess is for the line to reach the Triad terminals
by mid afternoon, followed by RDU near the end of the TAF period,
though timing is still a bit uncertain. MVFR or even IFR ceilings
and visibilities will be possible as the line moves through, along
with gusty winds.

Outlook: The line of showers and storms will continue to impact
southern and eastern parts of the area through the evening, with
sub-VFR conditions still possible. VFR conditions and dry weather
are expected to return Friday through the weekend.

&&

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

&&

$$
SYNOPSIS...Badgett
NEAR TERM...Badgett
SHORT TERM...Badgett
LONG TERM...Kren
AVIATION...Badgett/Danco