414
FXUS62 KRAH 050623
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
220 AM EDT Thu Jun 5 2025

.SYNOPSIS...
A developing area of low pressure along the GA/SC coast will track
northward over eastern portions of the Carolinas through tonight,
then shift off the southern Mid-Atlantic Coast on Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 910 PM Wednesday...

Minor changes with this evenings forecast update. The plume of
moisture is located off the SC coast this evening and expected to
move inland overnight. While the rain has held off with the deep dry
layer intact according to the 00z sounding from GSO, it is still
expected to slowly creep into the region overnight and bring steady
rain through early Thursday morning. Areas across the region are
expected to have periods of heavy rain during the morning commute
before becoming more scattered in coverage.  Lows overnight will be
in the low 60s north to mid/upper 60s south.

As of 330 PM Wednesday...Deep dryness was observed in both the GSO
and MHX RAOBs this morning, and the initial rain shield that will be
falling from lowering high through mid-level ceilings early tonight
will have a difficult time overcoming sub-cloud dryness. While a few
sprinkles may result this evening, measurable rain is unlikely to
materialize until later tonight-Thu morning, when low-level forcing
and moisture transport increase into the srn half of cntl NC, and
probably into the Triangle around the time of the Thu morning
commute. Low temperatures in the 60s.

&&

.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
As of 410 PM Wednesday...

*Wet, with a risk of a short-lived tornado or two and isolated
instances of flash flooding

A shortwave trough from the srn Appalachians to the e-cntl Gulf will
deamplify while lifting newd and across and offshore the Carolinas
and srn Middle Atlantic. It will be immediately preceded by an area
of diabatically-amplified mid-level vorticity from the area of
precipitation and embedded convection now centered over the Savannah
Basin, and an associated plume of PWs of around 2.0" and 150% of
normal.

At the surface, an area of low pressure is forecast to develop late
tonight from the Heart of GA to cntl SC, then track generally and
slowly newd across the srn Piedmont and wrn Sandhills of NC on Thu
and cntl and nrn Coastal Plain Thu night.

Rain will become increasingly-widespread, and moderate to heavy at
times over the srn half of cntl NC, early Thu morning, then spread
newd within a zone of low-level frontogenesis and isentropic ascent
and moisture transport that will all maximize along and immediately
northwest of the track of the slow-moving surface low. Despite
widespread, multi-layered cloudiness, surface theta-e advection
ahead of the low will support the development of weak surface-based
instability. Additionally, despite generally weak deep layer flow,
strongly veering wind profiles from ely at the surface to wswly at 3
km will support clockwise-curved hodographs between 0-3km and 150-
250 m2/s2 effective helicity and supportive of mini-supercells. Such
environments, particularly ones with low LCLs like that forecast for
Thursday, are characteristic of tropical tornado environments and
are similar to that which supported the back-to-back days of
tornadoes in Edgecombe Co. in May. Rain and storms will gradually
edge ewd and out of cntl NC Thu night, with clearing and areas of
fog, perhaps dense, possible over the far nw through srn NC
Piedmont Fri morning.

Clouds and precipitation will otherwise keep temperatures Thu about
8-10 F below average and in the 70s, followed by seasonably mild and
humid lows in the 60s.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
As of 245 PM Wednesday...

KEY POINTS:
- Unsettled weather during much of this long term period with lowest
rain chances on Friday and highest rain chances on Tuesday. Above-
climo rain chances the remaining days.
- Temps near to slightly above normal.

The long term period will be defined by daily, mostly diurnal,
shower and thunderstorm chances each day, as slowly-evolving broad
upper trough transits across the NE quadrant of North America, all
while sending shorter-wavelength disturbances across the Mid
Atlantic and Southeast states.  A series of relatively weak cold
fronts accompanying each of the upper short waves will approach and
stall or fizzle out across our area during this time, all of which
will contribute the daily shower/tstm chances.

Of the days in the long term, the driest day (PoP <20%) will be
Friday, thanks to our area briefly being in the subsident region
behind the departing sfc low that was noted in the near and short
term periods.  The wettest day (PoPs in the likely range) may end up
being Tuesday given that the sharpest of the short waves will be
passing by that day.  PoPs for the remaining days in the long-term
will generally be in the chance range, again, mainly diurnal in
nature.

Daytime temps during this time will generally be around or slightly
above normal (highs in the mid to upper 80s) given that the longwave
trough axis and frontal positions will remain mainly to our west
most of the period.  Night-time lows will be several degrees above
normal (upper 60s to around 70) due to the extensive cloud coverage.

Finally, for those with outdoor activities this weekend... the best
chance for rain both Saturday and Sunday will be mainly during the
afternoon and evening hours, while the overnight and morning hours
should be mostly dry.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
As of 220 AM Thursday...

A developing area of low pressure along the GA/SC coast will track
northward over eastern portions of the Carolinas through tonight,
then shift off the southern Mid-Atlantic Coast on Friday.

Tropical moisture lifting northward in association with this system
will support increasing showers from the south between 09 to 15z.
Rain may become heavy at times during the afternoon and early
evening, with scattered thunderstorms also possible, especially at
KFAY, and to a less extent at KRDU and KRWI.

Flight restrictions are expected to deteriorate to IFR at most
terminals, with some brief periods of LIFR possible. If the heavier
rain/showers remain east of the KINT and KGSO, those sites could
remain MVFR or even experience low-end VFR conditions.

Between 00 to 03z Friday, bulk of rain and storms will shift east of
the area, with only isolated showers possible across the eastern
terminals. As the area of low pressure shifts towards the coast,
drier air on the back side of the system will allow the sub-VFR
ceilings at KINT and KGSO to improve to VFR. However, ceilings at
KRDU, KFAY, and KRWI ceilings are expected to remain LIFR to IFR
until after daybreak Friday.

Outlook: Scattered showers/storms will be possible around the Triad
terminals Fri afternoon/evening. A series of fronts moving into and
stalling over the region will bring an unsettled period Sat through
Wed for showers/storms each afternoon and potential for sub-VFR
fog/stratus each morning.

&&

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

&&

$$
SYNOPSIS...CBL/MWS
NEAR TERM...CA/MWS
SHORT TERM...MWS
LONG TERM...np
AVIATION...CBL/Hartfield