Area Forecast Discussion
Issued by NWS Newport/Morehead, NC
Issued by NWS Newport/Morehead, NC
284
FXUS62 KMHX 201707
AFDMHX
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
Issued by National Weather Service Wakefield VA
107 PM EDT Thu Aug 20 2026
.WHAT HAS CHANGED...
No significant forecast changes. Updated full discussion and
aviation section for the afternoon forecast package and 18z
TAFs.
&&
.KEY MESSAGES...
1) Hot and humid conditions persist through the evening along
with isolated thunderstorms.
2) A more active pattern is expected from Friday through
Saturday, including a risk of strong to severe thunderstorms,
heavy rain, and flooding. Storm chances decrease on Sunday and
Monday.
&&
.DISCUSSION...
KEY MESSAGE 1...Light southerly flow continues this afternoon well
ahead of a cold front that is situated from West Virginia to
Pennsylvania. Heat indices are around or just above 105F with temps
of ~90F and dew points in the upper 70s. A Heat Advisory remains in
effect until 8 PM for the western half of the FA. A few showers have
developed. While MLCAPE has risen to 2000+ J/kg, deep layer shear is
weak and there really isn`t a forcing mechanism for convection
outside of the seabreeze. Coverage should be isolated with a risk of
gusty outflow winds of 40-50 mph in the strongest storms. Heat
indices may once again flirt with 105 degrees on Friday. However,
increased cloud cover and an increased risk of thunderstorms should
temper this risk some. A smaller Heat Advisory may be needed on
Friday, especially if thunderstorm activity is delayed later into
the day. Will hold off on additional headlines at this time, but will
reevaluate this evening/tonight.
KEY MESSAGE 2...Later this evening into the overnight (likely after
midnight), a broken line of thunderstorms is forecast to be
approaching the area from the NW. This convection will be tied to
the above mentioned cold front that will be moving SE out of
Virginia. Most short-term guidance insist that this convection will
be on a weakening trend as it approaches ENC. However, given the
increased forcing along the front, the convection may last longer
than some guidance suggests, even if elevated/weak in nature. Prior
to more substantial weakening, a risk of strong to marginally severe
outflow winds may accompany the thunderstorms as they reach the far
northern reaches of ENC during the early morning hours. Storms will
likely dissipate by 4-7 AM.
On Friday, the cold front will continue to slowly move south toward
the area before stalling in the vicinity of central/eastern NC. It
will interact with a very moist and strongly unstable airmass,
favoring the development of numerous thunderstorms. Deep layer shear
should get a bump up in the vicinity of the front. Combined with
strong surface heating/plenty of instability, a few strong to severe
storms are possible with the main threat being damaging to severe
(50 kt/58 mph) winds. However, given the slightly better shear and a
signal for rotating updrafts, a hail risk may develop in some of the
strongest/tallest cores.
In addition to the severe weather potential, there will also be a
risk of intense rainfall rates and hydro concerns. Strong
instability, 2"+ PWATs, increased large-scale and mesoscale forcing,
and the potential for training convection all point towards a risk
of flooding, including at least a few instances of flash flooding.
While no watches have been issued with the afternoon package, a
Flood Watch may eventually be needed for a portion of the area.
While the greatest coverage of storms (and highest flood threat) may
be more towards central NC, any storm will be capable of producing
localized rainfall amounts of 2-3+" in a short time. The 12z/20 HREF
has a ~30% neighborhood probability of 3" of rain in 3 hours across
west and northwest portions of the CWA. The potential for scattered
to numerous thunderstorms looks to continue into Saturday. However,
instability will be lower, and this may lead to a lowered risk of
severe weather. Heavy rain and flooding concerns may continue,
though. Precipitation chances will be lower on Sunday and Monday as
the low-level flow becomes NW then SW and the upper trough axis
pushes well to our northeast. It will be seasonably hot and humid
but well short of Heat Advisory criteria.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Mainly VFR through the period outside of showers/storms. Isolated
convection has developed early this afternoon and we`ll continue to
maintain a PROB30 mention for most TAF sites but will amend as
needed. After sunset (but mainly overnight/early Friday AM), an
elevated risk of TSRA may develop for at least the northern half of
ENC as a broken line of weakening SHRA and TSRA approaches from the
north.
Outlook: A heightened risk of TSRA is expected Friday into Saturday
thanks to a stalled front and various waves of low pressure
interacting with a very moist and unstable airmass. During this
time, widespread sub-VFR conditions can be expected, including a
risk of LIFR conditions at times during the strongest TSRA and
heaviest RA. Additionally, TSRA will carry a heightened risk of
gusty/erratic winds of 40kt+, especially on Friday. A risk of hail
up to 0.75" may accompany the strongest cores as well. Drier
conditions begin to move in Sunday and Monday with a reduced risk of
TSRA.
&&
.MARINE...
Benign conditions are expected outside thunderstorms for at least
the next few days. S-SW winds of 10-15kt are expected through
tonight. A few thunderstorms are possible over the waters this
afternoon and evening, with the risk increasing tonight. The
strongest storms this evening and tonight could produce gusty winds
of 30-40kt. A cold front stalls over the area on Friday with light
north winds expected across NE NC with S-SW winds south of the front
over the SE NC waters.
Outlook: The front will move back north as a warm front Friday night
and will be to our north on Saturday, with one or two areas of low
pressure lifting northeast along it. This will lead to a varying
wind pattern Friday evening/night but S-SW winds return on Saturday.
A more dominant southwesterly continues Sat night/Sunday.
The front and surface lows will support an increased risk of
thunderstorms Friday and Saturday for most waters. The strongest
thunderstorms will be capable of gusty winds of 40-50kt+ and perhaps
some hail. The thunderstorm risk is expected to lower by Sunday and
Monday.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Heat Advisory until 8 PM EDT this evening for NCZ044-079-080-
090>092-094-193>196-198-199.
MARINE...None.
&&
$$
DISCUSSION...RM/AKQ
AVIATION...AKQ
MARINE...RM/AKQ