103
FXUS62 KRAH 141906
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
306 PM EDT Tue May 14 2024

.SYNOPSIS...
A warm front will move northward along the Carolina coast this
afternoon and evening as low pressure approaches from the west.
Low pressure will shift to the coast tonight and Wednesday. A cold
front will move through the region Wednesday night and Thursday
morning.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 300 PM Tuesday...

Afternoon analysis reveals two areas worth noting from
satellite/radar. An MCV from this morning is presently just east of
Wilmington, NC. This MCV will continue to drift ENE and not be an
impact for the rest of today into the evening. A secondary but
noticeable circulation is over northern SC and about to move into
the southern Piedmont of central NC. Tied to this is a warm front
extending from the circulation over SE SC into eastern NC. The
northwest Piedmont remains in a wedge of easterly flow north of the
warm front. Latest radar trends have shown an uptick in showers and
embedded thunder along this circulation in north-central NC, where
dewpoints are in the low 70s. As this circulation lifts ENE over the
next few hours, showers will continue to advance northward over
central NC, with higher rainfall rates along/northwest of the low
over the northern/western Piedmont. Localized spots in this region
could pick up between 1 and 1.5 inches on top of what has already
fallen, which could cause an issue for poor drainage areas of the
Triad. Additional showers and embedded storms are favored to the
east of the low as it tracks ENE, roughly from the Sandhills to
central Coastal Plain, where 500 J/kg of CAPE could inch northward.
While the severe threat is much diminished, there could still be a
locally strong storm in this area, with the main impact being a
strong gusty wind or two.

Showers and some embedded storms are forecast to weaken between 7
and 9 PM as the low lifts off to our NE. There still remains a
chance of some isolated storms during the late evening to early
overnight, roughly from 10 pm to 2 am, across the western Piedmont
associated with the upper-low pivoting SE into TN/KY. Most guidance
still dies out the storms as they track east of the higher terrain,
owing to weaker forcing and little to no instability. Have left low-
end chance PoPs in this area, but most areas should be dry
overnight. Lows in the low to mid 60s

&&

.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
As of 300 PM Tuesday...

...There is a Marginal/Level 1 Threat for Severe Storms Wednesday
afternoon/early evening...

A compact upper low/shortwave trough centered over the TN Valley
Wednesday morning will move eastward through the region through
Wednesday night. At the surface, a warm front draped across northern
portions of the forecast area Wednesday morning will lift north into
Virginia. As it does so, the primary surface low associated with the
shortwave trough will begin to fill, with energy transferring to a
secondary/triple point low near the southern mid-Atlantic coast. The
accompanying trailing surface front will cross the area during the
late afternoon and evening.

In the wake of the warm front lifting north into VA, a period of
mostly dry conditions are expected through mid day, with a
noticeable reduction in PWATs noted across the area, which should
allow for some partial breaks in the broken and overcast cloud
cover.

Amidst BL dewpoints in the mid/upper 60s, tempered afternoon heating
will lead to moderate destablization. Coincident with the arrival of
the upper trough dynamics and surface front moving into the area
from the west,  scattered to numerous showers and storms will
develop across the area. Deep layer shear of 30-40 kts would be
sufficient to support a few strong to severe storm clusters, with
the main severe window between 4-9 PM. Damaging wind gusts and large
hail will be the primary threat, with a model signal of stronger
updrafts and severe potential along and south of HWY 64. Rain
chances will taper off west to east during the late evening and
overnight hours.

Highs will depend on the extent and duration of partial breaks in
cloud cover and resultant insolation. Highs ranging from mid/upper
70s north to lower 80s south. Lows in the upper 50s to lower 60s,
with HREF probabilities favoring the development of stratus over
fog.


.LONG TERM /THURSDAY THROUGH TUESDAY...
As of 300 PM Tuesday...

...Unsettled Weather Continues For the Weekend...

Thursday and Thursday night: Weak perturbations on the back-side of
the exiting shortwave trough could result in some isolated showers
and perhaps a rogue thunderstorm Thursday afternoon. Otherwise,
mostly dry with temps very comparable to Wednesday. Highs in the
mid/upper 70s north to lower/mid 80s south. Lows in the upper 50s to
lower 60s.

Friday through Sunday:

Models are starting to come into better agreement with the timing of
another compact upper low and associated  shortwave trough into the
SE US over the weekend. However, there still remains considerable
spread and uncertainty regarding the location/track of a potential
surface low through the region and related convective evolution
across the area.

Shortwave ridging will build briefly over the Eastern US Friday and
then offshore Friday night as the southern stream shortwave trough
progresses eastward into the lower MS Valley. A newd ejection of
shortwave disturbances, potentially convectively enhanced, within
the moistening SW flow aloft, could impact the Carolinas as early as
Friday afternoon/evening, especially across the western Piedmont,
followed by rain chances spreading east across the area Friday
night.

Saturday and Sunday currently looks like the wettest, most unsettled
period. Strong SWLY moisture transport with the approach of the
upper trough into the area is projected to advect daily record
maximum PWATs of 1.7 to 1.9" into the area Saturday. Amidst this
anomalously moisture, synoptic scale H5 falls on the order of 30-40m
coupled with strengthening upper level divergence as a 80-90kt jet
streak into the region will likely support widespread showers and/or
storms across central NC. Following a potential early Sunday lull, a
second round of showers and storms is likely as the vertically stack
low crosses the area. While there`s too much uncertain to
confidently access how much buoyancy will be realized across the
area, CSU ML probabilities and CIPs analogs indicate the potential
for a marginal/level 1 threat both days, especially across southern
portions of the forecast area. Will closely monitor this severe
weather potential. Temperatures will be highly dependent on rain
coverage, but the widespread cloud cover and high rain chances
should keep high temps near or just below normal. Highs ranging from
mid/upper 70s north to lower/mid 80s south. Lows in the 60s.

Monday and Tuesday: Medium range guidance suggests potential slowing
down/stalling of the upper trough along the SE US and western
Atlantic early next week which could lead to some lingering rain
chances. Will have to monitor these trends. For now, will indicate
mostly dry conditions with gradual warming.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
As of 135 PM Tuesday...

Largely IFR conditions are expected to start the TAF period. Waves
of showers will continue to progress northeast across the terminals
into the early evening hours. There remains a chance of some
embedded storms, but confidence is too low to mention at this time.
If any storms do occur, the best chance appears to be at FAY and
possibly RWI/RDU, in the 21-02Z time frame. Most storms though
should remain confined south and east of the terminals. Most
guidance favors showers ending between 00-03Z as lift and energy move
to the north and east. Energy will be slowest to exit at RWI.
Lingering drizzle may linger across the northern terminals behind a
wave of low pressure. There could be a secondary chance of showers
at GSO/INT in the 00-06z period with a front but most guidance is
not in agreement on its eastward maintenance due to stability.
Otherwise, IFR/LIFR conditions will remain overnight before lifting
to MVFR by mid-morning Wed and VFR between 16-18z. As for fog, there
is limited agreement in the guidance as low-level clouds persist.
Any fog potential appears most favored at GSO/INT/RDU, but have left
out any mention for now.

Outlook: LIFR/IFR fog/stratus will lift to VFR Wed afternoon.
Another period of showers and storms are possible Wed aftn/eve,
along with a chance of sub-VFR stratus or fog early Thu. VFR should
return Thu midday, with the next chance of showers possibly from
late Fri into Sun.

&&

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

&&

$$
SYNOPSIS...Badgett
NEAR TERM...Kren
SHORT TERM...CBL
LONG TERM...CBL
AVIATION...Kren