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672
FXUS62 KRAH 220730
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
230 AM EST Wed Jan 22 2025

.SYNOPSIS...
Arctic high pressure will remain entrenched across the region
through early Thursday. A wave of low pressure will track northeast
off the coast of the Carolinas Thursday into Friday, followed by
cold high pressure late Friday into Saturday.

&&

.NEAR TERM /TODAY AND TONIGHT/...
As of 230 AM Wednesday...

* Winter Weather Advisory remains in effect for hazardous driving
  conditions through mid-morning

* Winter Storm Warning remains in effect for up to an inch of
  additional accumulation prior to sunrise

* Cold Weather Advisory remains in effect until 10 am

The snow shield has all but exited central NC, holding on across the
southern Coastal Plain and Sampson County. Additional accumulations
in the Warning area, specifically just Sampson County, could see an
additional inch of snow. Latest observational reports indicate about
1 to 2.5 inches of snow fell across the warned area along/east of US-
1. Areas across the northwest Piedmont saw a dusting to one half
inch. Not many reports have come out of the eastern Sandhills to
southern Coastal Plain, but would not be surprised if a few isolated
locations report 3 or more inches in spots of the Coastal Plain. A
snow band of 25-30 dBZ on radar moved across these areas and likely
produced some isolated higher totals.

As the snow exits, conditions have improved dramatically. However,
the high cirrus shield persists thanks to the strong upper-level
jet. These high clouds should move east of our region by mid to late
morning, slowest in the east, leaving behind full sun above a fresh
blanket of snow. Those going outside or driving in the morning and
afternoon should be alert for hazardous driving conditions. Given
the very cold temperatures, many sidewalks and roadways are expected
to be ice or snow covered.

We remain under the cold airmass again today in the wake of the
departing system. Cold high pressure will be across the southern Mid-
Atlantic region. Gusts of 15-20 mph this morning combined with
temperatures in the teens and 20s will produce wind chills in the
single digits and teens. The Cold Advisory will be allowed to expire
after mid-morning. Highs will not rise much despite full sun
building in. Fresh snow cover will mean highs only in the upper 20s
to low 30s.

Tonight, a Winter Weather Advisory or special weather statement may
be needed to highlight the expected black ice and slick roads and
sidewalks, primarily along/east of US-1. We will see mid/high clouds
building toward daybreak Thu, but before that skies will be clear.
This along with clear skies will set up excellent radiational
cooling. Combined with fresh snow cover should support lows in the
single digits to lower teens, coldest along/east of US-1 where more
snow fell.

&&

.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
As of 230 AM Wednesday...

Aloft, swly flow will prevail over central NC, with the positively
tilted trough to the west. A s/w will lift newd from the OH Valley
through the nrn mid-Atlantic and Northeast US within the trough. The
trailing, stronger s/w will further sharpen the trough axis as it
swings through the cntl/srn Plains and into the mid-MS Valley. At
the surface, some ridging should continue over central NC on Thu as
an inverted trough amplifies off the Southeast/Carolina coast. There
could be multiple lows that form within the trough, one off the NC
coast Thu and another, stronger low off the Southeast US coast Thu
night. There is still some variability in the model guidance wrt the
timing and location of the low(s), but the overall trend has been
for any moisture associated with them to remain east of the area.
Have opted to maintain a dry forecast for Thu/Thu night. As for
temperatures, expect highs in the mid to upper 30s (which is 12-18
degrees below normal) and lows in the upper teens to mid 20s (5-12
degrees below normal).

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 230 AM Wednesday...

Friday through Sunday: Aloft, the trough will become more neutrally
tilted and less amplified as it and its embedded s/w move ewd from
the MS Valley through the East Coast and offshore Fri/Fri night. The
flow will become zonal over central NC Sat and Sun. At the surface,
while there could be some weak troughing over the area  early Fri
before the coastal low moves away and out over the Atlantic on, high
pressure should quickly move ewd across the Deep South and over the
Southeast US and Carolinas through Fri night and remain in place
through Sat night. The high should weaken over the region on Sun as
a lee trough sets up. Largely expect the forecast to remain dry
through at least Sat night/Sun. Temperatures will remain below
normal, but gradually moderate to near/slightly below normal from
Fri to Sun.

Sunday night onward: While models have come into better agreement
overall, there are still some differences wrt precipitation chances
Sun night/Mon. The closed upper low over CA/NV Sun will gradually
become cutoff from the parent trough by Monday as a s/w within the
parent trough moves ewd through the Plains and mid-MS Valley Sun
night. The s/w will then continue ewd through the TN Valley and mid-
Atlantic Mon/Mon night. The question regarding potential precip for
central NC lies with a srn stream plume of moisture off the western
Gulf into TX/LA Sun and if any of that moisture is able to get drawn
nwd, picked up by the s/w, and advected into the Carolinas Sun night
into Mon. The GFS continues to be the wetter solution, while the EC
keeps much of the moisture suppressed to the south. Given the
uncertainty, will continue with slight chance/chance for rain late
Sun night through Mon, drying out Mon night and remaining dry
through Tue. Expect primarily liquid precipitation if/where it
occurs, with the cold air chasing it on the back side. For now,
expect temperatures within a category or two of normal Sun-Tue.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
As of 1230 AM Wednesday...

The back edge of the snow has pushed east of GSO, INT, and RDU. The
FAY and RWI terminals have a few more hours of IFR/MVFR snow. The
03z RAP model has a good depiction of the latest trends. This along
with upstream radar returns and ASOS/AWOS observations, will hold
onto IFR snow restrictions at FAY/RWI till ~ 09z. A brief period of
LIFR is possible at FAY up to 07z. As the snow lifts east of the
terminals, some north to northeasterly gusts will be possible,
ranging from 15 to 20 kt, highest at FAY/RWI. These gusts should
diminish by midday Wed. VFR should prevail through the remainder of
the TAF period.

Outlook: VFR should prevail through Thu. A system crossing the
region Fri into Sat could bring wintry precipitation but confidence
with this remains low.

&&

.CLIMATE...
Record Low Maximum Temperatures:

January 22:
KGSO: 29/2014
KRDU: 27/1970

January 23:
KGSO: 28/1954
KFAY: 30/1970


Record Low Minimum Temperatures:

January 23:
KRDU: 8/1977
KFAY: 9/1970

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
Cold Weather Advisory until 10 AM EST this morning for
NCZ007>011-021>028-038>043-073>078-083>086-088-089.
Winter Weather Advisory until 7 AM EST this morning for NCZ011-
021-026-027-040>042-073>077-083-084.
Winter Storm Warning until 7 AM EST this morning for NCZ028-
043-078-085-086-088-089.
-- End Changed Discussion --

&&

$$

SYNOPSIS...Kren
NEAR TERM...Kren
SHORT TERM...KC
LONG TERM...KC
AVIATION...Kren
CLIMATE...RAH