839
FXUS62 KRAH 281927
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
326 PM EDT Tue Jul 28 2026

.WHAT HAS CHANGED...

* The relatively highest severe weather threat, at least through
  early this evening, has shifted to the wrn Piedmont, where Severe
  Thunderstorm Watch #526 is in effect through 8 PM EDT.

&&

.KEY MESSAGES...
As of 325 PM Tuesday...

1) There remains a (conditional) Slight risk, Level 2 of 5, for
severe thunderstorms throughout cntl NC through this evening, though
the greatest threat/highest confidence area will be over the
Piedmont at least for the next several hours.

2) Dry through Saturday, then unsettled into next week.

&&

.DISCUSSION...
As of 325 PM Tuesday...

KEY MESSAGE 1... There remains a (conditional) Slight risk, Level 2
of 5, for severe thunderstorms throughout cntl NC through this
evening, though the greatest threat/highest confidence area will be
over the Piedmont at least for the next several hours.

The models indicate a closed mid/upr-level low will develop across
the lwr Great Lakes and nrn Middle Atlantic through early Wed,
within a shortwave trough now progressing across that region per
GOES-E water vapor satellite data. In cyclonic, nwly flow through
the associated trough base, at least a couple of lower amplitude
perturbations, one of which may be convectively-amplified within the
band of frontal convection now over the lwr OH Valley, are forecast
to dig across and offshore the Middle Atlantic. An unseasonably
strong belt of wnwly/nwly 700-500 mb winds of up to 30-40 kts are
forecast and already observed in VWP data over the srn Middle
Atlantic. Meanwhile, 850 mb-centered moisture transport now directed
into the cntl Appalachians will develop ewd and across the srn
Middle Atlantic through this evening.

At the surface and in the low-levels, an MLCAPE minimum over cntl NC
and Southside VA per SPC mesoanalysis data has resulted from
mid/high-level debris cloudiness and remnant stratiform rain and
related limited diurnal destabilization, and also from the presence
of somewhat shallower low-level moisture east of the Appalachians,
indicated by 12Z-observed mean mixing ratios around 13.5 g/kg at
RNK/GSO versus 16-17 g/kg upstream at BNA/ILN. The swrn periphery of
lingering stability and inhibition over cntl NC has been marked by
an outflow and differential heating boundary draped at 19Z from near
TNB to VUJ. This boundary may retreat slightly newd and into the nw
NC Piedmont this afternoon, while a synoptic cold front across WV/KY
will continue to progress swd/sewd across the srn Middle Atlantic
and srn Appalachians.

Deep convection will probably continue to develop this afternoon,
with scattered coverage between the outflow boundary and the
synoptic front and a broken line along the latter, then propagate
generally sewd and  into the NC Piedmont (particularly wrn portions)
through this evening. Shear profiles will be supportive of
supercells, particularly where coverage remains scattered and cells
discrete, versus a tendency for bowing segments within the broken
line of frontal convection. It remains unclear to what degree any
additional development may occur over the ne Piedmont and Coastal
Plain this evening, deeper in the aforementioned stability there and
where the severe threat is even more conditional and uncertain.
However, a lack of cumulus there and presence of stable/billow
clouds nearby over much of cntl and nrn VA suggest any such threat
will be delayed relative to the nearer storms approaching Watch
#526; and no local extensions to the current Watch or issuance of a
new one altogether for locations to its east are imminently
anticipated.


Key Message 2: Dry through Saturday, then unsettled into next week.

Late Week through Weekend: High pressure shifts from the Upper
Mississippi Valley on Wednesday, settling over the Mid-Atlantic by
Friday. Expect near to below-average temperatures and fair weather
through Saturday afternoon. The next round of precipitation arrives
late Saturday evening into Sunday morning as tropical moisture
interacts with a developing stationary boundary.

Into Next Week: Unsettled weather persists through at least mid-week
as the stationary boundary lingers overhead. Plentiful Gulf and
Atlantic moisture will tap into this lingering  boundary, bringing
multiple rounds of showers and isolated thunderstorms across the
region over several days.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
As of 155 PM Tuesday...

Low VFR to MVFR visibility restrictions in a band of now mostly
stratiform rain will be possible for the next couple of hours at RWI
and Piedmont sites. Deep convection will meanwhile continue to
develop --with scattered coverage along an outflow and differential
heating boundary draped at 18Z from near TNB to EXX and in a broken
line along a synoptic cold front over the lwr OH Valley-- then
propagate generally sewd and across the NC Piedmont between 19Z-02Z
and, with lower probability of occurrence and if it holds together
amid lesser instability and debris cloudiness from the
aforementioned stratiform rain, into the RWI and FAY between 23-04Z.

In the wake of the convection, clearing aloft will result atop
residually moist low-levels and soils tonight, such that areas of
mist/fog and low stratus may develop especially at ern sites. VFR
conditions and a surface nwly wind, with gustiness into the teens
kts especially over the Piedmont, will follow for Wed.

Outlook: VFR conditions are generally expected until probably
Sunday, when lift ahead of a mid/upr-level low approaching from the
OH Valley will favor above average chances of showers/storms and
flight restrictions.

&&

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

&&

$$

DISCUSSION...MWS/CA
AVIATION...MWS