757
FXUS62 KRAH 211846
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
245 PM EDT Fri Aug 21 2026

.WHAT HAS CHANGED...

*  Severe Thunderstorm Watch issued for southern counties this
   afternoon.

*  Flood watch expanded to Anson county.

&&

.KEY MESSAGES...
As of 245 PM Friday...

1) There is a risk of excessive rainfall across the
entire forecast area, primarily during the afternoon and early
evening.

2) There is a risk of severe thunderstorms across the
entire forecast area this afternoon and evening, with the greatest
threat along and south of US-64.

&&

.DISCUSSION...
As of 245 PM Friday...

KEY MESSAGE 1... There is a risk of excessive rainfall across the
entire forecast area, primarily during the afternoon and early
evening.

The Weather Prediction Center has the entire forecast area
under a slight (level 2 of 4) risk for excessive rainfall. Locally,
a flood watch was issued overnight for much of the area, excluding
the Triad and areas northeast of the Triangle, going through
Saturday morning. A boundary is set up across southern counties,
having pushed slightly farther south than anticipated. From Sanford
and Erwin to the northeast, low clouds and northerly flow have kept
temperatures primarily in the 70s, while out in the Triad and
southern counties, more sun has allowed for temperatures to climb in
the 80s and lower 90s. While convective-allowing models have
performed poorly over the last day or two, there are still
indications that thunderstorms currently developing along the North
Carolina/South Carolina border will expand in coverage and push to
the north during the afternoon. With slow storm movement, deep
moisture, and "skinny CAPE", these storms will have the potential to
bring multiple inches of rain in a short period of time. In
particular, the 12Z HREF shows approximately a 50% potential for 3
inches of rain in 3 hours just to the south of the Triangle during
the late afternoon. Showers and thunderstorms will likely peak in
coverage before sunset, continue into the evening, then rapidly drop
off after midnight.

KEY MESSAGE 2... There is a risk of severe thunderstorms across the
entire forecast area this afternoon and evening, with the greatest
threat along and south of US-64.

The Storm Prediction Center has placed the Triad and counties
along the VA/NC border in a marginal (level 1 of 5) risk, with the
rest of the forecast area in a slight (level 2 of 5) risk. The
primary threat is damaging winds, although large hail cannot be
ruled out. As of 2pm, there is minimal MLCAPE and large amounts of
CIN along and to the north of US-64, while the greatest instability
is to the south of the boundary that was discussed in Key Message 1.
That is the primary reason that the Severe Thunderstorm Watch that
was issued around 1:30pm only included the southern half of the
forecast area and did not extend any farther to the north. Across
Cumberland and Sampson counties, the MLCAPE is as high as 3000 J/kg.
There is at least 30 kt of effective bulk shear across the forecast
area, which should help to eventually organize storms. The greatest
threat for severe thunderstorms should be over the next several
hours, and the Severe Thunderstorm Watch is valid through 9pm.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
As of 145 PM Friday...

TAF period: Confidence is lower than normal in the details of these
TAFs due to the uncertainty with thunderstorms and where they will
develop today; however, confidence is high that all terminals will
experience at least some rain this afternoon and have low ceilings
overnight.

Thunderstorms are beginning to develop along the North
Carolina/South Carolina border and will increase in coverage as they
move northeast. Have gone with prevailing showers at all sites,
continuing a TEMPO group during the most likely 4 hour window for
thunderstorms. Visibility reductions with the storms may be slightly
greater than normal considering heavy rain rates are expected today.
There is a bit of uncertainty as to how long the prevailing rain
will last into this evening, but IFR ceilings are likely to quickly
expand from INT/GSO south and east after dark, with all sites
expected to eventually develop LIFR ceilings. The ceilings should
lift to MVFR by late Saturday morning, with scattered showers
developing by that time at RDU/FAY/RWI.

Outlook: Precipitation will primarily be at RDU/FAY/RWI Saturday
afternoon, although it cannot be ruled out at INT/GSO. Widespread
restrictions are not currently forecast for any sites Saturday
night, although if precipitation is heavy enough, there could be
local restrictions. Dry VFR conditions are expected Sunday through
Tuesday night before a chance of thunderstorms returns to all
terminals Wednesday.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Saturday morning for NCZ023>025-039>043-
073>078-083>086-088-089.

&&

$$

DISCUSSION...Green
AVIATION...Green