Winston-Salem, North Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

064
FXUS62 KRAH 171843
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
243 PM EDT Thu Sep 17 2026

.WHAT HAS CHANGED...

* The boundary of the Level 1/Marginal risk for severe storms
  capable of damaging downbursts on Friday was expanded to include
  more of the Piedmont (srn and nwrn), though forecast rationale has
  not changed.

* An increasing likelihood for cold air damming during the middle of
  next week necessitated a reduction in high temperatures and
  diurnal temperature ranges; and additional downward adjustments
  may be needed.

&&

.KEY MESSAGES...
As of 240 PM Thursday...

1) It will be hot Fri, prior to scattered to locally numerous
showers/storms that will focus over the Piedmont and wrn Sandhills
Fri afternoon and night and redevelop over the srn half of NC
(especially along and south of US Hwy 64) on a less hot but still
humid Sat.

2) Monday will feature another round of scattered to locally
numerous showers/storms.

3) Nely flow and cold air damming will probably yield much cooler
and cloudier conditions, possibly accompanied by periods of mainly
light rain, by the middle of next week.

&&

.DISCUSSION...
As of 240 PM Thursday...

KEY MESSAGE 1... It will be hot Fri, prior to scattered to locally
numerous showers/storms that will focus over the Piedmont and wrn
Sandhills Fri afternoon and night and redevelop over the srn half of
NC (especially along and south of US Hwy 64) on a less hot but still
humid Sat.

An anomalously strong subtropical ridge will weaken while drifting
from the TN and lwr MS Valleys swwd to the srn Plains through Sat,
during which time at least a couple of convectively-enhanced mid-
level disturbances may develop and track through its nern periphery
from the OH Valley to the srn Middle Atlantic and Carolinas.

At the surface, a lead effective front and composite outflow
stretching somewhat discontinuously from nrn VA wwd through srn and
cntl OH, IN, and IL, will progress swd and across VA and perhaps nrn
NC by 12Z Fri. This boundary may be indiscernible from a lee trough
that will extend across the Piedmont during the morning and
subsequently progress sewd and across cntl NC through the day and
serve as the leading edge of both less hot temperatures and richer
low-level moisture that will displace a residually-dry/continental
pre-frontal airmass deposited by a preceding Canadian high and dry
air ridge. A closely-spaced, trailing synoptic front and nrn bound
of rich low-level moisture characterized by ~70 F surface dewpoints,
now stretching across the nrn Middle Atlantic, srn Lower MI, and nrn
IL, will also progress swd and through VA during the day Fri and
into-through cntl NC Fri night through Sat.

Instability and shower/storm chances will probably become maximized
in the moist axis between these two boundaries, favored over the
Piedmont and wrn Sandhills Fri afternoon-night. Isolated strong to
locally damaging downbursts will be possible where storms occur
during the afternoon-early evening, when steep low-level lapse rates
will favor multi-cell organization and preferential cell development
along shared and swd-moving outflow, amid weak nly to nnely mean
winds. Weak shear and mid-level lapse rates, above the steep low-
level ones driven by strong insolation/diurnal heating, will
otherwise limit severe potential.

Redevelopment or re-intensification of otherwise shallow convection
on Sat will then be favored over the srn half of NC (especially
along and south of US Hwy 64) on a less hot but still humid Sat.


KEY MESSAGE 2... Monday will feature another round of scattered to
locally numerous showers/storms.

The models indicate a weak frontal wave will develop across the OH
Valley and across and offshore the Middle Atlantic Sun-Sun night,
with the trailing cold front forecast to settle through cntl NC on
Mon. Hot and humid conditions, and moderate instability, will result
ahead of that cold front and focus for additional, scattered to
locally numerous convection over cntl NC on Mon.


KEY MESSAGE 3... Nely flow and cold air damming will probably yield
much cooler and cloudier conditions, possibly accompanied by periods
of mainly light rain, during the middle of next week.

Following Monday`s cold frontal passage, a strong (~1035 mb) surface
high is forecast to progress across cntl and ern Canada, while
ridging swd across the Middle Atlantic/Carolinas. This high/
anticyclone will be maintained by confluent mid/upr-level flow
downstream of a Rex blocking configuration invof the upr Great Lakes
and trailing a vigorous trough forecast to progress through Atlantic
Canada. Nely low-level flow and cold air damming will probably
result over the srn Middle Atlantic/Carolinas and yield much cooler
and cloudier conditions, possibly accompanied by periods of mainly
light rain, during the middle of next week.

&&

.AVIATION /16Z THURSDAY THROUGH TUESDAY/...
As of 1140 AM Thursday...

Scattered showers/storms are expected to develop from wrn through
Southside VA through this afternoon; and a couple of isolated ones
may drift generally swd and into the INT/GSO vicinity mainly between
22Z-01Z, before dissipating. VFR conditions are expected otherwise
and elsewhere until just beyond the 18Z TAF period, when Friday
afternoon through night a couple of cold fronts will trigger
scattered to locally numerous showers and storms over cntl NC.

Outlook: A risk of convection will linger along the passing fronts
on Saturday, especially over the srn half of NC and including at FAY.
Nely flow behind the fronts will otherwise increase the likelihood
of IFR-MVFR ceilings, lowest and most prolonged over the Piedmont
(especially at INT/GSO), both Saturday and Sunday mornings. Stronger
nely flow, and an increasing likelihood of cold air damming, will
favor additional sub-VFR conditions and periods of light rain during
the middle of next week (as early as Tue).

&&

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

&&

$$

DISCUSSION...MWS
AVIATION...MWS