Rocky Mount, North Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

543
FXUS62 KRAH 241137
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
637 AM EST Sat Jan 24 2026

.WHAT HAS CHANGED...
As of 400 AM Saturday...

* There will probably be a corridor of more sleet accumulation at
  the expense of freezing rain accrual than currently forecast,
  probably over a portion of the nw Piedmont. This probability is
  not explicitly forecast at this time; and it may not be until the
  nowcasting phase, when observational trends indicate when and
  where it may occur.

* No notable changes have otherwise been made to the ongoing
  forecast.

&&

.KEY MESSAGES...
As of 400 AM Saturday...

1) Incoming, Arctic cold and wind today will feel as cold as teens,
to single digits this morning over the nrn Piedmont and nrn Coastal
Plain.

2) Winter Weather headlines, and expected Moderate to Major Winter
Storm Severity Impacts, remain unchanged for the winter storm that
will affect central NC mainly tonight through Sunday night.

3) The coldest temperatures of the season (so far) are expected from
Monday night through the end of the week, with daytime highs and
overnight lows 20 to 25 degrees below normal. Near zero or sub-zero
wind chills are expected at times later this week.

&&

.DISCUSSION...
As of 400 AM Saturday...

KEY MESSAGES 1 and 2...

A polar vortex centered in 00Z/24th upr air charts along the QC/NL
border will progress across the Labrador Sea and nw N. Atlantic this
weekend. Some degree of confluent flow, favorable for the
maintenance of underlying high pressure and cold air damming east of
the Appalachians, will remain its wake. However, backing of that
flow and a broad area of height falls ahead of a complex and net,
positively-tilted trough that will progress from the Rockies to the
Great Lakes through mid MS Valley --and one which will be preceded
by the deamplifying and accelerating remnants of a mid/upr-level
cyclone now nearing the coast of the cntl Baja Peninsula-- will
cause that underlying Arctic high to weaken and retreat newd/
poleward during the latter half of the weekend. That pattern and
backing of the flow aloft, and to swly in the mid-levels, will also
cause mid-level warmth to surge newd across the Carolinas and Middle
Atlantic, such that at or below zero 850 mb temperatures over cntl
NC this morning will be replaced by Sun evening, by 10-15 C ones
observed from TX to the Gulf coast this past evening.

At the surface, a 1045 mb, Arctic high now centered over MN and with
minus 30-40 F surface temperatures, and up to 10 F lower surface
dewpoints, will progress ewd and across the Great Lakes, nrn Middle
Atlantic, and Northeast at around 1040 mb through 12Z Sun, then
retreat poleward and weaken considerably to sub-1030 mb across
Atlantic Canada by 12Z Mon. It will be favorably strong and located
and dammed east of the Appalachians for a significant (classical,
diabatically-enhanced) cold air damming episode through much of Sun,
before weakening and retreating poleward late Sun and especially Sun
night. Despite its retreat and demise later this weekend, the
magnitude of its related Arctic cold and dry, with associated sub-
zero F surface dewpoints all the way into srn VA already this
morning, may allow its influence to linger longer through the
duration of the event than its increasingly unfavorable position and
strength with time would suggest. Around the srn periphery of the
Arctic high, a pattern of Miller Type "B" or Miller Type "A/B"
cyclogenesis will result, with a couple of initial lows forecast to
track across the TN and OH Valleys (inland) and along and offshore
the srn Middle Atlantic coast (coastal), respectively, during which
time a third low will follow and track across GA and the ern
Carolinas. This surface pattern will favor corridors of predominant
precipitation-types that will include and be highlighted by
significant accumulation/accrual of sleet/freezing rain over cntl
NC. An associated surface wet bulb freezing line that will become
established along the NC coast today will probably retreat nwwd
across the NC Coastal Plain and ern Sandhills by Sun evening, then
*possibly* into the Piedmont later Sun night-Mon morning. How
quickly and far nwwd it can retreat will have ramifications on how
much additional icing may result with a sw to ne-oriented band of
briefly heavy frontal precipitation forecast to sweep across the
region Sun evening-early Sun night.

The sensible weather related to the synoptic pattern described above
will feature an increasingly cloudy and cold, but dry Sat, with
virga that will likely begin to reach the ground across the nrn
Piedmont by this evening. It will do so during a time when partial
thickness values and top-down both suggest snow would be the
predominant precipitation type, for the first few or so hours, and
when most any snow would be able to accumulate - perhaps an inch or
so over the nrn Piedmont, depending upon how quickly it can reach
the ground. The time window for snow will be limited, however, as
the aforementioned significant warming aloft (centered around 850
mb) noses rapidly newd and promotes a changeover to sleet overnight,
and as strong QG ascent (related to the mid-level warming via WAA)
increases throughout cntl NC.

Further, significant warming aloft will ensue Sun-Sun night, when
forecast 850-700 mb partial thickness values are off-the-nomogram
high at around 1600+ meters, with an associated general sse to nnw
mixing with or changeover to a predominance of freezing rain, as
those warm nose temperatures increase well above values to
completely melt any snow/ice nuclei falling through it. Despite that
complete melting, underlying cold nose temperatures are forecast to
be atypically cold (~minus 10C) and sufficiently so to yield
additional ice nucleation in the lowest couple of thousand ft AGL;
and that may allow for periods of continued snow and sleet
production, with crystal habits of the former that would favor
columns/prisms/needles that would not accumulate very efficiently,
particularly if accompanied by freezing rain as expected. The
aforementioned nwwd retreat of the surface wet bulb freezing line
into at least the Sandhills and srn-cntl Coastal Plain will favor a
changeover to all rain there Sun evening-early Sun night, and
possibly into parts of the Piedmont overnight.

Forecast storm total liquid equivalent amounts remain similar to the
previous forecast: near one inch over the srn Coastal Plain, where a
significant portion of that will probably come from the frontal
precipitation band when above freezing surface temperatures may
support just rain Sun night, to 1.75-2" in the far nrn/nw Piedmont
(Triad).

We remain confident in the aforementioned corridors of precipitation
types that will be mostly ice and a combination of sleet/freezing
rain over most of cntl NC, except mostly freezing rain and then rain
across the Sandhills and srn to cntl Coastal Plain, but exact
amounts remain somewhat in question given uncertainty with how long
sleet over the Piedmont will be the predominant p-type before
yielding to freezing rain; and *accumulation of one will come at the
expense of the other*. Deterministic storm total frozen (mostly
sleet) and freezing rain totals also remain relatively unchanged
from previous forecasts, but there will probably be a corridor where
more sleet accumulates at the expense of freezing rain and may
consequently reduce impacts, specifically those related to power
outages; and that corridor appears most likely over portions of the
nw Piedmont.


Key Message 3...The coldest temperatures of the season (so far) are
expected from Monday night through the end of the week, with daytime
highs and overnight lows 20 to 25 degrees below normal. Near zero or
sub-zero wind chills are expected at times later this week.

In the wake of the departing winter storm, very cold air will
overspread the entirety of the East Coast. Across NC, this will
translate to steady or falling temperatures through the day on
Monday with highs ranging from the upper 20s to mid 30s. Monday
night`s low is projected to be the coldest night of the season so
far as a 1032mb surface high makes its way into western NC. The
combination of clear skies and light winds should yield lows in the
lower single digits in the NW Piedmont, and in the low to mid teens
in the southern Coastal Plain. Cold Weather headlines will almost
certainly be needed during this time period as wind chill readings
will plummet below 0 along the NC/VA border and hover in the lower
single digits elsewhere. Temperatures should slowly moderate Tuesday
into Wednesday but highs and lows will remain well below normal with
highs both days in the low to mid 30s. Overnight lows in the low to
mid teens.

A fast moving shortwave trough embedded within northwesterly flow
aloft is forecast to cross the mountains into the Mid Atlantic on
Thursday. At this point nearly all ensemble cluster solutions agree
that this trough will swing through the area, although precip
amounts (if any) remain in doubt. Given downslope drying, it`s hard
to support more than a slight chance mention of precip late
Wednesday into Thursday along the NC/VA border. If nothing else,
this trough will usher in a secondary reinforcing shot of cold air.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
As of 636 AM Saturday...

12Z Update: The cold front has cleared through central NC, behind
which we continue to see some enely gustiness especially at
KRWI/KFAY. Still expecting this to subside some this morning and
through the rest of the 24 hr TAF period. Timing of winter
precipitation still appears similar to what`s described in the
previous discussion below. However, latest guidance is trending
towards hanging onto sleet a little longer than previously thought
(especially at KRDU/KFAY/KRWI). These sites will transition to more-
so freezing rain later Sunday and continue through Sunday evening.
Ceilings will also fall to IFR early Sunday morning.

Previous discussion:

A strong cold front continues to sag south from VA this morning. As
it clears through central NC the next few hours, expect winds to
turn more enely and for periodic gusts of 20 to 25 kts (especially
at KRWI/KFAY) through sunrise. Gusts will mellow some from sunrise
through the end of the 24 hr TAF period, but remain largely from the
nne.

A winter storm with varying mixed precipitation will start to arrive
at the end of the 24 hr TAF period. At KINT/KGSO, forecast soundings
would support a few hours of pure snow (and associated typical LIFR
visibilities) for a few hours tonight before transitioning to sleet
by ~06Z.  At KRDU, sleet will be possible at onset, but a quick
transition to freezing rain seems likely.  KFAY/KRWI will likely
start off as freezing rain near the end of the 06Z TAF period. MVFR
ceilings will also accompany the incoming precipitation later
tonight.

Outlook: Ceilings will further tank Sunday as winter precipitation
continues through late Sunday evening/night. Additionally, extreme
LLWS is expected Sunday night. Conditions will improve by Monday and
VFR is expected thereafter, although gusty northwest winds will
continue Monday during the daylight hours.

&&

.CLIMATE...

Record Low Maximum Temperatures:

January 25:
KGSO: 23/1940
KRDU: 28/2013
KFAY: 30/2013


Record Low Temperatures:

January 26:
KRDU: 10/1940

January 27:
KRDU: 8/1940
KFAY: 11/1940

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 1 PM Saturday to 1 PM EST Monday for
NCZ007-021>024-038-039.
Winter Storm Warning from 7 PM Saturday to 1 PM EST Monday for
NCZ008>011-025>028-040>043-073>077-083>086.
Winter Weather Advisory from 7 PM Saturday to 1 PM EST Monday for
NCZ078-088-089.

&&

$$

DISCUSSION...MWS/Leins
AVIATION..Luchetti/AS