360
FXUS62 KRAH 031845
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
145 PM EST Wed Dec 3 2025

.SYNOPSIS...
Continental Polar high pressure will migrate across the Southeast
through early Thursday. A dry cold front will lead Arctic high
pressure across and offshore the Middle Atlantic later Thursday
through Friday, while weak waves of low pressure will track along a
wavy frontal zone from the northern Gulf to offshore the Southeast
coast.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1240 PM Wednesday...

* Unseasonably cold with variable cloudiness through the overnight
  period.

A broad area of 1022mb high pressure leaking across the southern
Appalachians will continue to drift eastward throughout the day
before becoming increasingly diffuse by Thurs morning. Patches of
flat strato-cumulus clouds, visible on satellite imagery over the
western Piedmont into the Sandhills and Coastal Plain, will provide
locally greater coverage of partly to mostly cloudy skies through
the afternoon before gradually thinning late this evening into
tonight.

Light surface winds will become more south to southwesterly through
the afternoon and keep surface dew points fairly steady as moisture
north of the stalled occluded front to our south counteracts the
very dry air just above the PBL. Limited horizontal moisture
advection is expected overnight within the weak pressure gradient,
but relatively moist afternoon crossover temperatures and pockets of
heavily saturated soils from Tues rainfall, may result in patchy
fog. Widespread fog is not anticipated as waves of cirrus with
varying thickness shift over the region overnight and should provide
an unfavorable factor to an otherwise excellent radiational cooling
night for radiation fog. Lows tonight will settle in the mid 20s to
low 30s.

&&

.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
As of 425 AM Wednesday...

* Increasing clouds and milder/more-seasonable Thu

* Precipitation developing, including a rain/snow mix that will
  probably transition to all snow for several hours across the nrn
  Piedmont, late Thu night-Fri morning

The mid/upr-level height gradient will tighten across the lower mid-
latitudes and contribute to the intensification of a powerful, 150-
175 kt upr-level jet across the OH Valley and Middle Atlantic, where
u-wind anomalies are forecast to reach 3 sigma. It will do so in
response to the pivot of a negatively-tilted, nrn branch polar
shortwave trough across and offshore the Middle Atlantic and
Northeast, and as the srn branch polar and sub-tropical streams
merge and phase downstream of a couple of ejecting shortwave troughs
now centered over the Southwest and near 25N/125W, respectively. A
strengthening low/mid-level WAA regime, and also frontogenesis, will
result within the elongated jet entrance region, equatorward of the
jet core and across the Southeast.

At the surface, a dry cold front will lead Arctic high pressure
across the OH Valley and Middle Atlantic Thu and swd into NC by Fri
morning. The Arctic high will be favorably strong (~1028-1030 mb)
and located (over PA) for wintry precipitation in cntl NC Thu night
but then quickly weaken and progress offshore on Friday.

After a mostly sunny start to Thu, considerable mid and high-level
moisture, and associated combination of altocumulus and cirrostratus
ceilings, will overspread cntl NC through the afternoon and evening.
Despite the increasing clouds, temperatures Thu will probably
moderate into the 50s courtesy of both modification of the cP high
and airmass over the Southeast, and also wly/downslope flow at 850
mb.

Lift, initially centered in the mid-levels between 700-500 mb, will
cause a precipitation shield to blossom across the TN Valley and
expand quickly newd and across the srn Appalachians and especially
wrn Carolinas Thu night. Partial thickness and point forecast
soundings (top-down) suggest that as the precipitation shield begins
to overspread cntl NC Thu night, its nrn periphery will probably
transition from a mix of rain and snow across the nrn Piedmont to
all snow for several hours roughly along and north of I-85 Fri
morning, as thermal profiles trend toward deep, near freezing
isothermal, including into the near surface layer owing to diabatic
contributions from both evaporational cooling and melting of snow. A
very light coating may begin to accumulate over the nw Piedmont by
sunrise, with some additional light accumulation through the
morning, before thermal profiles trend above freezing amid continued
mid-level WAA and a lack of continued surface cold/dry advection
from the transitory and weakening surface high.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 140 PM Wednesday...

* Mixed precipitation event possible Sun night into Mon, but
  synoptic pattern is typically unfavorable for impactful snowfall.

* Bitterly cold temperatures possible Tues morning.

A strong and elongated jet will be in place Sat morning from the
southern Plains through the Mid-Atlantic and into the Atlantic with
150-175kts at 250mb (1-2 SD above normal). On the equatorward side
of the jet, anomalous deep-layer moisture will remain in place with
perturbed H5 flow directed across the Southeast and Mid-Atlantic.
This should favor a continued chance for light rain possible
through Sun. Although the mid-levels should still be cold enough for
ice-crystal formation, lack of saturation above -8C and warming low-
levels will keep all precipitation liquid through Sun.

Forecast uncertainty increases with an added wrinkle of potential p-
type concerns Sun night into Mon. The primary driver in uncertainty
with this next system is the amplitude and propagation speed of the
northern stream wave as it shifts across eastern Canada and the
Northeast. Cluster analysis from the old 00z grand-ensemble suggest
a quicker northern stream wave and shortwave ridging moving across
the Northeast, resulting in a more favorable surface high placement
ahead of the next wave, would provide a greater concern for snowfall
in the Piedmont and northern Coastal Plain. Climatology suggest cold
air arriving `just in time` for the onset of precipitation is
typically not favorable for measurable snow in the Carolinas. This
methodology and leaning on climatology keeps the forecast all rain
for now.

Forecast turns quieter and colder early next week as cold high
pressure on the backside of the Sun night/Mon system filters into
the area and PWAT values drop to well below normal. Tues morning
could be bitterly cold with the surface high centered directly over
the area. Lows in the low/mid 20s to upper teens Tues morning
certainly appear possible.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
As of 1240 PM Wednesday...

Scattered to broken MVFR stratocumulus has indeed blossomed over the
Coastal Plain and eastern Sandhills (nearest FAY) this afternoon. A
separate area around 3,500 to 5,000 ft stratocumulus from SC has
spread north into the southern Piedmont with fleeting low-VFR cigs
as far north as the Triad terminals. The MVFR stratocu may affect
FAY vicinity for the next several hours before lifting to around
3,000-4,000 ft this evening. There is a potential for FAY to remain
around high-MVFR cigs into late this evening, but opted for a more
optimistic forecast for now. Cooling temperatures tonight, atop
saturated soil from yesterday`s rain, will probably promote the
development of at least patchy fog Thu morning, with highest
probability of occurrence and lowest visibility restrictions from
near CLT to FAY to OCW to as far north as RWI.

Outlook: Another storm system is expected Fri into Sat and will
likely bring flight restrictions to all central NC terminals. A
period of snow/sleet remains possible for the northern terminals
(GSO/INT/RDU) Fri morning before transitioning to all rain by the
afternoon.

&&

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

&&

$$

SYNOPSIS...MWS
NEAR TERM...AS
SHORT TERM...MWS
LONG TERM...AS
AVIATION...AS/MWS