Marcus, North Carolina Weather Forecast Discussion

602
FXUS62 KRAH 251049
AFDRAH
Area Forecast Discussion
National Weather Service Raleigh NC
650 AM EDT Thu Sep 25 2025
.SYNOPSIS...
A surface cold front and an upper level trough will hold to our west
through early Friday, then both will push slowly eastward through
the Appalachians and into the Carolinas through the weekend,
bringing wet and unsettled weather.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
As of 315 AM Thursday...
* Continued hot and humid, with much above normal temperatures
  especially in the east.
* Scattered showers and storms expected NW today, with isolated
  strong to severe storms possible; the chance for showers and
  isolated storms expands areawide for tonight.
We`ll remain in a moist and strengthening SW low level flow today,
ahead of a surface front stretching from NE through the Ohio Valley
to the lower Miss Valley. This front is situated on the eastern edge
of the positively tilted mid level trough extending from MI SW
through OK, and as this trough eases ESE through tonight, the
surface front will likewise drift ESE into the central and S
Appalachians. SW mid level flow accelerates over our area through
tonight, with multiple weak perturbations tracking NE through the
Carolinas. PW will be above normal areawide but most so over our NW
half, where values are expected to be 125-150% of normal for much of
the day, and this is evident on GOES WV imagery which shows a deep
moisture plume from the central Gulf coast NE through the western
Carolinas. Amidst this favorable moisture in our NW, forcing for
ascent will be sufficient for at least scattered showers and storms.
In addition to the weak vorticity centers tracking through the W
Piedmont today, providing shots of dynamic support for lift,
moderate CAPE is expected this afternoon, bolstered by high surface
dewpoints in the upper 60s/lower 70s, all despite rather modest mid
level lapse rates. Fewer clouds in the east will allow for greater
heating and higher CAPE there as compared to the cloudier west,
although deep layer bulk shear will be greater across the NW. As has
been noted in previous discussions, the risk of strong to isolated
severe storms will be greatest where (and if) there is an overlap of
moderate to high CAPE and stronger shear, and given the high water
content over the Triad, isolated strong wet downbursts could occur
from mid afternoon into early evening. Will carry chance pops W of
Hwy 1, with good chances in the Triad today. Chance pops should then
expand areawide by this evening as the deep moisture plume eases
eastward further into central NC, and despite loss of heating, the
very warm low levels and high dewpoints should maintain some SBCAPE
(mostly sub-1K J/kg) well into the night areawide. Expect highs
today in the mid 80s NW, slightly lower than Wed with more clouds,
while the rest of the CWA should again see highs in the low-mid 90s,
around 10-15 deg F above normal. As this will be the third
consecutive day of much above normal heat and humidity, heat stress
and the risk for heat illnesses will be elevated. Tonight will be
muggy, with very warm lows in the upper 60s to lower 70s. -GIH
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
As of 230 AM Thursday...
* Minor urban and poor drainage flooding possible late Fri afternoon
  into the late evening hours.
The positively-tilted trough axis extending from the Lower Great
Lakes southwest through Louisiana will begin to separate. The base
of the trough will become closed and become neutrally-tilted and
stall just west of the Carolinas by 12z Sat. A steady stream of
anomalous deep-layer moisture and highly perturbed mid-level flow
will be directed from the Southeast through the Carolinas into the
Mid-Atlantic and continue well beyond Fri night.
The finer details of the forecast will remain relatively uncertain
and depend on how the weather unfolds on Thurs, especially with
regard to location of a prior outflow boundary and placement of an
inverted trough axis over the Carolinas. These will play a role in
the areal extent of the warm and unstable sector as well as where a
weak area of low pressure, expected to develop within an area of
convection over central Gulf coast Fri afternoon, tracks through
late Fri afternoon and into the overnight period. This will likely
be where greatest rainfall totals of 1-3 inches will be most
probable with the general consensus in available forecast guidance
somewhere across the eastern Piedmont, Sandhills, and/or Coastal
Plain. Flash-flood guidance is quite high in this region (around
4.5" in 3hrs outside of urban areas), so widespread flooding is not
expected. However, the pattern supports a marginal risk, level 1 out
of 4, for minor urban and poor drainage flooding.
Overall severe threat is low (< 5% from SPC), but the presence of
anomalous moisture, potential for moderate instability (> 1500 J/kg
of MLCAPE), and some storm organization within multicell clusters
and storm collisions may result in isolated strong wet-downbursts.
&&.
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 230 AM Thursday...
* Prolonged cloudy conditions and periods of rain likely to continue
  off and on into early next week.
* Although tropical development is becoming likely for 94L, timing,
  track, and intensity all have a high degree of uncertainty Sunday
  into Monday.
Forecast confidence remains high on widespread rain for Saturday as
the Carolinas into the southern Mid-Atlantic will be in a favorable
position relative the the slow moving trough and the upper jet. For
the most part, this should be a favorable soaking rain for the
forecast region, but with some modest elevated instability to tap
into, some periods of heavy rain and thunder will be possible. For
now, available guidance suggests 0.25" to around 1" is most likely
for most of the forecast area and pockets of higher totals of 2" are
possible from 12z Sat to 12z Sun.
The time period of the greatest forecast uncertainty is Sun through
Tues. This is stemming from a combination of low predictability
features, such as the cutoff low and how it evolves during this time
and invest 94L. From an ensemble approach, most guidance slowly
shifts the plume of anomalous moisture eastward towards the I-95
corridor Sun and then off the coast by Mon, but periods of light to
moderate rain still appear possible during this time with closer
proximity to the mid/upper low and weak upper divergence.
As for Invest 94L there appears to be loosely two scenarios
beginning to take shape and is largely a timing uncertainty on how
quickly it lifts northward Sun into Mon. A slower solution results
in 94L meandering off the Southeast Coast before getting kicked back
out east with strengthening southwesterly flow aloft and increasing
shear over the western Atlantic. In contrast, a quicker solution
results in 94L getting pulled north quickly and more likely to reach
the Carolina coast between Mon and Mon night. The slower solution is
the favored solution among latest guidance, but a trend to watch in
subsequent forecast runs.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
As of 650 AM Thursday...
Central NC will stay within a strengthening SW flow today and
tonight, ahead of a slow-moving surface front and upper level trough
sitting to our NW. Rain chances will increase today, mainly at
western terminals, before spreading E tonight.
At KINT/KGSO: A period of light showers is possible through 13z in
the Triad region, along with a chance for brief MVFR vsbys and
IFR/LIFR cigs. Otherwise, VFR conditions will dominate after 14z-
15z, then scattered showers and storms will move into the Triad area
after 19z, bringing the possibility for strong/shifting winds with
height and downpours producing MVFR vsbys. A few showers will linger
from 00z to 06z, then MVFR to IFR cigs are expected to develop after
07z. Surface winds will be light/variable through mid morning, then
from the SW 8-14 kts gusting to 15-20 kts through 00z before
becoming light from the SW through tonight.
At KRDU, VFR conditions are expected to dominate, with periods of
mid level clouds passing overhead. There is a chance for showers and
storms starting in the late afternoon, mainly after 21z, lasting
into the evening, but coverage should be lower than what is expected
further W in the Triad. MVFR conditions trending to IFR are expected
starting after 08z. Surface winds will be from the SW, mostly under
10 kts, but with gusts to 15-20 kts in the afternoon.
At KRWI/KFAY, VFR conditions are expected to dominate, although fair
skies should allow development of patchy fog toward sunrise, mainly
MVFR but may briefly drop to IFR. Any fog should lift by 14z. An
isolated shower or storm may drift near these sites late in the TAF
valid period, starting mid evening. Surface winds will be from the
SW, mostly under 10 kts, but with gusts to 15-20 kts in the
afternoon.
Looking beyond 12z Fri, a few showers and isolated storms are likely
to persist areawide through daybreak, and there is a good chance for
sub-VFR stratus or fog until mid morning Fri. As our weather becomes
increasingly wet and unsettled heading into the weekend, the chance
for sub-VFR conditions will increase and remain high Sat through Mon
with numerous showers and storms possible. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Hartfield
NEAR TERM...Hartfield
SHORT TERM...Swiggett
LONG TERM...Swiggett
AVIATION...CBL/Hartfield

NWS RAH Office Area Forecast Discussion