-- Discussion containing changed information from previous version are highlighted. --
759
FXUS62 KRAH 011724
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
124 PM EDT Wed May 1 2024

.SYNOPSIS...
An upper level trough will shift slowly eastward across the central
and eastern Carolinas through this afternoon. Deep high pressure
will build over the Carolinas and Southeast this evening through
Friday, resulting in very warm temperatures. A series of weak upper
level disturbances will move through the region Friday evening
through Sunday, bringing periods of unsettled weather.

&&

.NEAR TERM /TODAY THROUGH TONIGHT/...
As of 1025 AM Wednesday...

No major changes with the forecast other than tweaking up cloud
cover along and to the east of a pressure trough and moisture
boundary separating mid/upper 60s to its east and mid/upper 50s to
its west. As of 14z surface analysis, the boundary stretches from
southeast VA and extends southwest through the Triangle and now
south of Albemarle area. This boundary will slowly sag southeast
through the afternoon and provide a western extent of potential
isolated showers and storms this afternoon.

Forecast discussion as of 230 AM Wednesday...

The mid-upper low (and its weak surface counterpart trough) shifts
slowly eastward, so too will the sufficient moisture through the
column to support convection with heating. Until this time, though,
as our eastern sections heat up with surface dewpoints still in the
60s and PWs still over 1", we should see enough CAPE develop for
scattered showers and a few storms pop up this afternoon, mainly E
of I-95. Some sea breeze interaction is possible as well. HREF mean
soundings in the E Coastal Plain show 500-1000 J/kg SBCAPE this
afternoon, although shear is rather poor, so expect little more than
the typical gusty winds in/near any showers or storms. Locations
along and W of Hwy 1 should stay mostly dry as the mid-upper levels
dry and stabilize. Lingering mid clouds in the E through midday may
temper heating and CAPE a bit, while west sections should see quite
a bit of sunshine today as heights rise aloft. Expect highs of 80-
86, 5-10 deg above normal, hottest in the SW.

Skies should trend mostly clear tonight, although patchy fog is
possible across the E, given the light winds, low dewpoint
depression, and good radiational cooling. Lows in the upper 50s to
lower 60s. -GIH

&&

.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
As of 300 AM Wednesday...

Dry and warmer weather is likely Thu with rising heights aloft as
mid level ridging builds strongly over the Carolinas from the SW and
PWs fall to generally under 1". Light onshore (SE) low level flow
develops over the E Carolinas, which should facilitate an inland sea
breeze push into our area, and this may result in some convective cu
in the afternoon from the Triangle to the S and E. Otherwise, skies
should be mostly sunny through sunset, with a trend to clear skies
Thu night. As thicknesses rise to 25-30 m above normal, expect highs
of 85-90, around 10 deg above normal. Lows in the upper 50s to lower
60s, perhaps mid 60s far SE. -GIH

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 350 AM Wednesday...

Unsettled weather expected over the weekend into early next week,
but confidence in the timing of possible showers and storms, as well
as total rainfall amounts remains relatively low .

A strong ridge over the southeast US will slowly shift east and
offshore by Saturday, allowing weak height falls aloft and the
passage of a series of weak shortwaves in more moisture-favorable
west-southwest flow aloft.

At the surface high pressure over eastern Canada will extend through
New England and nudge a backdoor cold into northeastern North
Carolina by Saturday morning, while a surface low migrates through
the Ohio Valley and its trailing weak cold front advances east into
the Appalachians by Sunday.  The weak front may not actually make it
into NC, but the presence of disturbances aloft along with
precipitable water increasing to over 1.5 inches should result in
scattered to numerous showers and a moist and less capped warm
sector, augmented by diurnal heating and instability, and the timing
of the disturbances.  A limiting factor in the coverage of precip
may be the absence of greater larger scale forcing and increased
cover/reduced instability as highs are expected to drop back into
the upper 70s and lower 80s.

The best time for precip appears to be late Saturday through Sunday,
though the models appear to be trending at least slightly wetter for
Monday and Tuesday as well.  All-in-all, near normal rainfall of up
to one inch is possible across the area, but the pattern doesn`t
appear to favor much more than that on the whole.  After the brief
relative cool down, upper 80s look to return by midweek next week

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
-- Changed Discussion --
As of 120 PM Wednesday...

An area of agitated cumulus in the vicinity of FAY has been
producing brief showers that redevelop along a prior showers outflow
for the past hour. So far, the dry air aloft has prevented enough
hydrometeors at or above -10C and have been void of lightning so far
this afternoon. Regional satellite has shown some glaciation on the
tops of a couple updrafts, so isolated lightning can not be ruled
out through the afternoon. Cumulus clouds in the vicinity of RWI
have remained flat and shallow which has prompted the removal of the
tempo in favor of a period of VCSH. Shallow moisture advection
behind the seabreeze may result in patchy fog affecting the Coastal
Plain (FAY/RWI) with less confidence on impacts at RDU. Fog/stratus
will quickly clear after daybreak with light winds generally out of
the southeast through the afternoon with scattered fair weather
cumulus.

Looking beyond 18z Thu, VFR conditions will prevail through Fri. The
chance for sub-VFR conditions within scattered to numerous showers
and storms will increase starting Fri night, lasting through Sun, as
a series of disturbances passes over the region. Areas of early-
morning fog are also expected. -GIH
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...Hartfield
NEAR TERM...Swiggett/Hartfield
SHORT TERM...Hartfield
LONG TERM...BLS
AVIATION...Swiggett/Hartfield