833
FXUS62 KRAH 161848
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
245 PM EDT Sun Aug 16 2026

.WHAT HAS CHANGED...

* Another Heat Advisory has been issued for Monday for southern and
  eastern portions of central NC.

* The chance for a few strong to severe storms has increased for
  much of the Piedmont of NC for Monday.

&&

.KEY MESSAGES...
As of 245 PM Sunday...

1) A Heat Advisory remains in effect today for parts of the Triangle
and south-central NC, and we`ve issued another Heat Advisory for the
Triangle to the S and E for Mon. The hot weather will continue into
mid week, will gradually lowering heat indices mid through late
week.

2) The threat for a few strong to severe storms continues through
Mon. We have a Marginal (level 1 of 5) risk of severe thunderstorms
across the northern half of central NC for the rest of today, and a
Slight (level 2 of 5) risk in the Piedmont on Mon. Damaging winds
are the primary threat.

3) Rain and thunderstorm chances will increase from late Thursday
through the weekend as a slow-moving cold front stalls over the
region, though exact timing and impacts remain uncertain.

&&

.DISCUSSION...
As of 245 AM Sunday...

KEY MESSAGE 1... A Heat Advisory remains in effect today for parts
of the Triangle and south-central NC, and we`ve issued another Heat
Advisory for the Triangle to the S and E for Mon. The hot weather
will continue into mid week, will gradually lowering heat indices
mid through late week.

Heating has been curbed somewhat today by this morning`s areas of
low clouds as well as the early-onset of convection across parts of
the Sandhills and far N CWA. But several locations have still
managed to reach a 105F heat index today, as pockets of strong
heating combine with high dewpoints in the mid-upper 70s. We should
see a bit less cloudiness Mon morning, and with low level
thicknesses expected to reach 20 m above normal, highs should reach
the mid 90s to near 100F. The small bit of good news is that the
dewpoints tomorrow are expected to be slightly lower than today,
dipping into the 70-76 range with mixing in the afternoon, with
these lower readings in the west, and this should help keep heat
indices from reaching criteria for an Extreme Heat Warning, although
certainly this will be assessed further tonight and monitored
closely on Mon. But a Heat Advisory is warranted for all but NW and
VA border portions of the CWA, with heat index values expected to
reach 105-109F. NWS Heat Risk, which is based on how unusual and/or
long-lived this heat is, as well as on past CDC heat-illness data,
reaches a level 3 (out of 4) nearly everywhere Mon, suggesting that
this heat could be particularly dangerous.

Temps may be a bit less hot on Tue, but still elevated over the S
and E CWA, where the long duration of this hot stretch will add to
the already-high heat stress.


KEY MESSAGE 2... The threat for a few strong to severe storms
continues through Mon. We have a Marginal (level 1 of 5) risk of
severe thunderstorms across the northern half of central NC for the
rest of today, and a Slight (level 2 of 5) risk in the Piedmont on
Mon. Damaging winds are the primary threat.

A few strong to severe storms remain possible today and Mon. Deep
layer bulk shear remains poor today, under 20 kts, which will limit
the intensity and duration of any updraft. But SBCAPE has reached
2500-4000 J/kg thus far (according to RAP-based mesoanalysis) with a
DCAPE over 800 J/kg much of the area, highest SW, and with PWs still
around 2" or up to 130%-140% of normal, isolated water-loaded
downdrafts remain possible, leading to localized strong to severe
gusts into early this evening. On Mon, the SBCAPE may be a bit
lower, but our deep layer shear is expected to be around 25 kts,
with added forcing for ascent provided by an approaching MCV
expected later in the day from the NW. In particular, convection
over the NC mountains may maintain strength with better organization
as they track ESE into the NC Piedmont, again with damaging winds as
the primary threat, from mid afternoon through mid evening.

Storm coverage is expected to decrease and push to our SE sections
on Tue, as a slug of drier air with lower PW spreads in from the WNW.


KEY MESSAGE 3... Rain and thunderstorm chances will increase from
late Thursday through the weekend as a slow-moving cold front stalls
over the region, though exact timing and impacts remain uncertain.

As we head into late week, a stronger cold front is expected to move
into the region. Forecast guidance shows precipitation chances
increasing late Thursday ahead of a slow moving trough. The frontal
boundary is expected to stall over the region before eventually
washing out. This lingering boundary will act as a focus for daily
rain and thunderstorm chances returning Friday afternoon/evening and
persisting through the weekend. Given how far out this is, there are
still several details to look into. Will closely monitor forecast
trends over the coming days for any adjustments in the timing,
amounts, and exact placement of this frontal boundary which will
then result in a better idea for how isolated or widespread precip
chances will be over the weekend.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
As of 110 PM Sunday...

Areas of sct-bkn MVFR clouds persist over much of the area including
near RDU/RWI/FAY, but these clouds will continue to break up and
lift over the next hour or two, yielding mainly VFR conditions after
20z away from storms. Showers and storms are quickly developing just
N and NW of INT/GSO and over south and east areas from VUJ to HRJ to
GSB, and as these drift toward the SE and expand in scope through
mid afternoon, all 5 TAF sites will see a threat for storms for a
few hours from mid afternoon through early evening, first at INT/GSO
and FAY then soon thereafter at RDU/RWI. Gusty winds over 30 kts and
brief sub-VFR conditions are expected in and near these storms.
After 00z, VFR cigs/vsbys should again prevail, although there is a
good chance for patchy MVFR fog 09z-13z early Mon morning at all
sites, especially those that see rain today. Surface winds will be
mostly light, under 10 kts, from the S or SW through 00z,
light/variable tonight, then from the W or WNW after 15z Mon.

Looking beyond 18z Mon, another round of scattered showers and
storms is expected 18z-22z, highest chance at INT/GSO. The better
chances should then shift to mainly south and southeast areas for
Tue-Thu. Higher rain chance are expected areawide Fri ahead of an
approaching upper level low pressure trough. Outside of storms,
generally VFR conditions are expected, although a few hours of
patchy early-morning sub-VFR fog/stratus may occur each day, with
the highest chances in areas that see rain.

&&

.CLIMATE...

Record High Temperatures:

August 17: KGSO: 99/1988 KRDU: 99/1997 KFAY: 104/1954

August 18: KFAY: 98/1988

August 20: KFAY: 102/2007


Record High Minimum Temperatures:

August 16: KGSO: 75/2016 KRDU: 76/2007 KFAY: 78/2005

August 17: KGSO: 75/2010 KRDU: 76/2024 KFAY: 78/2007

August 18: KGSO: 75/2017 KRDU: 77/1995 KFAY: 78/2021

August 19: KRDU: 77/1988 KFAY: 76/1940

August 20: KRDU: 75/2007 KFAY: 78/2005

August 21: KRDU: 76/2009 KFAY: 77/2005

August 22: KFAY: 75/2018


&&

.RAH WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 11 AM to 8 PM EDT Monday for NCZ024>028-040>043-
073>078-083>086-088-089.
Heat Advisory until 8 PM EDT this evening for NCZ025-040>042-073>077-
083>086-088-089.

&&

$$

DISCUSSION...Hartfield/CA
AVIATION...Hartfield