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000
FXUS62 KRAH 210711
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
310 AM EDT Sun Apr 21 2024

.SYNOPSIS...
A couple of mid and upper-level disturbances will approach and
interact with a frontal zone that will settle off the coast of the
Carolinas through this evening. High pressure will otherwise
build across the Middle-Atlantic states through Tuesday.

&&

.NEAR TERM /TODAY THROUGH TONIGHT/...
As of 215 AM Sunday...

Light rain developing with a chilly NE breeze this morning.

Occasional rain this afternoon, ending from the west this afternoon
and in the east this evening.

Temperatures falling into the 40s and 50s through the day.


A cluster of showers and thunderstorms continues to threaten hail
Sampson and Wayne counties this hour. This activity is quickly
moving SE and should be out of our region before 300 AM. Weak low
pressure was located over the southern Coastal Plain where dew
points were in the 60s. The trailing front delineated very dry air
with dew points in the 20s/30s NW NC and VA to 50s/60s over central
and eastern NC.

Meanwhile, a couple of shortwave perturbations now over NE and the
N TX , respectively, will come into phase as they pivot
across the mid MS Valley through 12Z. The associated ascent will
cause a separate area of light, stratiform rain to overspread cntl
NC generally between 08-14Z, with a combination of CAA and
evaporative cooling that will result in low temperatures
falling into the 40s and 50s through the morning. Highs will occur
at the current time, with falling temperatures expected through the
day with the occasional light rain.

The rainfall amounts are expected to range from less than 0.10 in
the NW to around a third to a half inch in the south and east. The
rain is expected to taper off through the afternoon west, and in the
east-central regions this evening.

Cloudiness will be slow to clear tonight with lows in the 40s, some
upper 30s north-central Piedmont.

&&

.SHORT TERM /MONDAY AND MONDAY NIGHT/...
As of 220 AM Sunday...

CAA northerly flow will keep temperatures in the lower to mid 60s
Monday as high pressure to our northwest builds into the region.
After some morning cloudiness east, skies will become mostly sunny.

Clear and chilly conditions are expected Monday night with lows in
the upper 30s to lower 40s. Some mid 30s are possible in the
typically coldest locations.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 305 AM Sunday...

Mostly dry forecast with only scattered sprinkles possible on Wed.
Forecast uncertainty for rain chances increases Fri night into Sat.

Shortwave ridging and elongated high pressure will spread across the
Carolinas on Tues and favor dry weather with only wisps of mid/upper
level moisture through the afternoon. An eager northern stream wave
on the southern periphery of a parent low will pivot across the
Great Lakes region and through the northern Mid-Atlantic Wed. The
better 700mb WAA and main shield of precipitation will be well
displaced north of central NC, but a trailing tail of mid-level
moisture and a progressive cold front may result in some light rain,
but mostly sprinkles, leaking across the mountains and into the
Piedmont of NC Wed morning into the early afternoon. Latest ensemble
and deterministic guidance is confident that the cold front should
progress completely through central NC by Thurs morning, but where
it becomes quasi-stationary largely remains in question with the 00z
GFS stalling this boundary noticeably farther north than 12z ECMWF.

The next minimal chance for precipitation will be associated with a
shortwave ejected from the Four Corners region Thurs morning and
riding up into the Northern Plains early Sat morning. The synoptic
forcing for ascent will stay west of the Appalachian mountains with
only weak isentropic ascent along the 290-295K surface a top the
quasi-stationary front. The 00z GFS and the 12z GEFS members are
much flatter with the building high amplitude ridging and largely
make up the precipitation chances during this time. Other model
guidance strengthens the surface high to the northeast and keeps the
lower level moisture return west of the mountains and thus minimal
precipitation chances. Below normal temperatures Fri will begin to
moderate towards above normal heading into the weekend.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
As of 155 AM Sunday...

VFR ceilings are expected to lower to MVFR then IFR with light
rain today. VSBYS will mostly lower from VFR to MVFR with the
light rain through the day.

Flight conditions will be lowest and rain relatively heaviest at
RDU/FAY/RWI. A period of NE gustiness may also result this
morning to 25kt, especially at RWI and RDU, as an area of surface
low pressure develops/ strengthens along the aforementioned,
offshore front.

Outlook: Light rain and flight restrictions will end from southwest
to northeast Sunday evening. High pressure through early next week,
then the passage of a moisture-starved cold front Wednesday
afternoon-evening, will favor VFR conditions through most of the
next week.

&&

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

&&

$$
SYNOPSIS...MWS/pwb
NEAR TERM...Badgett
SHORT TERM...Badgett
LONG TERM...Swiggett
AVIATION...Badgett/MWS