608
FXUS62 KRAH 240111
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
811 PM EST Sat Nov 23 2024

.SYNOPSIS...
High pressure will settle across the southeastern United States for
the second half of the weekend. Two cold fronts will cross the
region this coming week - one on Tuesday and another on Thursday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 811 PM Saturday...

....Frost Advisory In Effect Tonight Across the eastern Sandhills
and coastal plain of NC where the growing season continues...

The pressure gradient between the deep area of low pressure over
Nova Scotia and surface high pressure over the Deep South will
continue to relax. Winds have decoupled with most locations already
reporting calm winds. Some broken orographically enhanced cirrus is
still hanging on across the far northern counties, but should
dissipate with time as the moisture lifts north and flow atop the
mountains becomes less orthogonal. Strong radiational cooling will
allow for colder temps than last night. Lows tonight 30-35, coldest
across the western and northern Piedmont.

While freezing temps ended the the growing season across the
Piedmont and western Sandhills earlier this week, the eastern
Sandhills and coastal plains have yet to experience a freeze. Thus,
a frost advisory is in effect for these counties.


&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
As of 235 PM Saturday...

Mid-level ridging over the MS valley will shift east into our area
during the afternoon and evening. Heights will progressively
continue to rise. At the surface, high pressure over the region will
shift offshore, allowing a return south-southwesterly WAA pattern to
build into the area. Other than some high clouds through the
day/evening, it should be a pleasant afternoon with temperatures
some 3-7 degrees above normal. The MAV/MET statistical guidance for
today is running some 2-4 degrees too low for today`s highs, so we
kept highs for Sun still closer to the NBM 90th or even 95th
percentile. That puts our highs in the low to mid 60s north to the
mid to upper 60s in the Sandhills and Triangle region. Although
southerly flow will persist Sun night, winds should be relatively
light. Lows will be closer to average in the upper 30s to low 40s,
except mid 30s in outlying areas.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
As of 235 PM Saturday...

* A period of active/wet weather is becoming increasingly likely for
  holiday travel Thanksgiving into Fri.

The work week will begin with a low amplitude by active mid/upper
level pattern across the CONUS. Most relevant for central NC will be
a trough situated over the northern-central Plains Mon morning that
will take on a negative tilt as it pivots across the Great Lakes and
Ohio Valley Tues. The associated surface low will similarly track
well to the north of our region, but an attendant cold front will
sweep across the forecast area Tues morning through the early
afternoon. NWP guidance continues to highlight a classic `Carolina-
split` with only a handful of models suggesting measurable
precipitation. As the decaying FGEN band and associated moisture
from upstream precipitation traverse the mountains, expect mostly a
thickening/lowering of the cloud cover and mostly sprinkles on Tues
(relatively equal chances areawide). Will continue the previous
forecast trend and lower highs a degree or two with widespread
cloud, sprinkles and early fropa favoring cooler highs.

The main area of concern in the extended will be unfortunately
around and after Thanksgiving (Thurs and Fri). Although there are
still considerable difference among ensemble guidance on timing and
placement of important features, a period of active/wet weather is
likely sometime from Thurs through Fri evening. The most notable
difference is the track of the lead area of low pressure as it
shifts from the KY/TN Valley towards the Mid-Atlantic. The EPS has
been consistently farther north than the GEFS and results in a
farther north development of a secondary low along the front over
the Virginias rather than over the Carolinas. The 12z GEFS has
shifted subtly farther north towards the 00z EPS solution, but there
is too much uncertainty to shift the forecast too far in this
direction just yet. An important note, if the farther north trend
continues, this would increase the risk for severe weather but
predictability remains low at this time.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
As of 612 PM Saturday...

TAF period: VFR conditions will continue over the next 24 hours at
all terminals.  The mid to high level clouds will continue to
dissipate the next few hours. Gusts have largely subsided, and sfc
flow should remain light overnight and into Sunday.

Outlook: A brief MVFR ceiling or sprinkle cannot be ruled out Monday
night into Tuesday morning. Another chance of precipitation will
arrive for Thursday. The rest of the period should be dry with VFR
conditions.

&&

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

&&

$$
SYNOPSIS...Green
NEAR TERM...CBL/Green
SHORT TERM...Kren
LONG TERM...Swiggett
AVIATION...Luchetti/Green