Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/11/25
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
905 PM EST Fri Jan 10 2025
.SYNOPSIS...
Low pressure is expected to lift northeast from the Gulf coast
today, tracking along the Carolina coast tonight into Saturday,
bringing additional winter weather to the region. Dry conditions
return later this weekend into early next week.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
As of 900 PM EST Friday...
Key Messages:
- Winter Storm Warnings remain in effect for southside, central,
and eastern Virginia. Winter Storm Advisories continue north
of Richmond, and for southeast Virginia and northeast North
Carolina.
- Moderate to locally heavy snowfall will result in 2-5" snow
accumulations with a higher band of 5-6+" within the broader
Winter Storm Warning footprint.
An area of low pressure continues to shift northeastward from the
Gulf Coast towards the Carolina Coast overnight. Snow has begun to
move into the forecast area, with snow being reported across the
southern Piedmont so far. Dewpoints have increased 8-10 degrees in
these locations as the lower levels are gradually becoming more
saturated, allowing the snow to reach the ground. There is a batch
of higher reflectivity moving along the state line as well
indicating bigger snowflakes. This is resulting in snow quickly
covering surfaces and even some roadways. Expect snow to become more
widespread over the next few hours, followed by an increase in snow-
rates, resulting in impacts to travel. The only part of the forecast
that was changed was upping snow totals very slightly along a line
from roughly Clarksville to Wakefield to the Peninsula due to
trends in the latest high- resolution models. This is where
locally higher amounts up to 5-6" will be possible. Also
accounted for the possibility of a period of sleet across NE
NC. Otherwise, the forecast is on track -- please see the
previous discussion below.
As of 410 PM EST Friday...
Low pressure over the Gulf Coast is moving across the SE US towards
the Mid-Atlantic, dropping snow from KS to SC. Tonight, the low
pressure will move through the area bringing snow and some wintry
mix precip to the south of the area before turning to rain. 12z
model guidance has supported an increase in QPF, in addition to the
system over-performing in the SE US, showing a more amplified
system. COnfidence in seeing a mesoscale band of enhanced lift
from strong FGEN has increased snowfall amounts to 3-5" for the
areas in the WSW, which is relatively between a line ENE from
Cumberland County to Accomack County and a line ENE from central
NC Northampton County to City of Norfolk. Models are currently
aiming the heavier band generally along and ~25 mi ether side of
a line ENE from Lunenburg county to the peninsula and into the
Eastern Shore amounting snowfalls of 5-6+". Outside the
Warnings, regions in the Winter Storm Advisories can expect 1-4"
of snowfall. Have upgraded East Hanover County and Lancaster
County from an Advisory to a Warning as snowfall amounts are
anticipated to be within warning criteria (4" in 12 hrs).
A warm nose both at the surface and aloft will push in the area from
the SE. This will prevent a full snow event for the SE of the FA.
The event will begin as all snow tonight and then transition into a
mixed precip in SE VA/NE NC before becoming plain rain. HRRR and RAP
models have decreased the amount of ice with this storm, now only
showing a few hundredths of an inch in inland NC. Soundings
additionally suggest that any ZR would be brief and not accumulate
much. Have decreased ice amounts slightly, but a light glazing up to
0.1" to the SE of the FA is still possible.
This system is quick moving and moisture will quickly decrease from
W to E after sunrise. Temps Sat will warm up to the upper 30s to
lower 40s. If there is more snowpack than expected, temps may
struggle to reach that high. Sat night will continue to be below
average, refreezing any precip, with lows in the upper 10s to lower
20s.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
As of 410 PM EST Friday...
Key Messages:
- Cold temperatures continue with warmest temperatures of the
week on Monday in the mid 40s.
After the low pressure system that brings the wintry precip moves
offshore, high pressure will move into the area with the core of the
high over the Appalachian mountains. High temps Sun will reach the
upper 30s to lower 40s across the area with clear skies. Sun night
will continue to be cold with temps in the upper 10s to lower 20s.
Winds will be calm, so currently no concern for a CWY Sat or Sun
night. Mon will be the warmest day of the week with high temps in
the mid 40s (upper 40s in SE VA/NE NC). Mon continues to be dry with
clear skies.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 245 PM EST Friday...
Key Messages:
- Another surge of well below normal temperatures is expected
Tuesday through Thursday, moderating by Friday. Generally dry
through the period.
- Cold Weather Advisories will likely be needed at times next
week, especially Tuesday night/early Wednesday and Wednesday
night/early Thursday.
Models remain in good agreement in regards to another anomalous,
deep upper trough diving ESE from the Upper Midwest Monday
night, pushing off the New England coast by Wednesday. It still
appears to remain dry for the local area with strong sfc high
pressure over the midwest slowly ridging S to the Gulf coast and
SE states later in the week. This pattern brings 850 mb temperatures
down to -10C to -15C Tuesday-early Thursday, resulting in another
round of very cold/well below normal temperatures through Thursday.
Highs will mainly be in the 30s and lows in the teens through
this timeframe with a blustery NW wind making it feel even
colder. Wednesday is still looking to be the coldest day of the
forecast period with high temperatures only in the upper 20s to
around 30 across the north, to the mid 30s farther south. With
the expected wind, apparent temperatures Wed afternoon are
likely to remain in the teens across the MD eastern shore, with
20s elsewhere. Cold Weather Advisories will likely be needed at
times next week, with the highest potential at this time being
Tuesday night/Wednesday AM and Wednesday night/Thursday AM where
we may see wind chill values as low as 0 to 5 degrees across
the northern half of the area and upper single digits to lower
teens south. Temperatures moderate towards the end of the week
as the mid/upper flow becomes more zonal, with high temperatures
perhaps close to normal by Friday.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As of 630 PM EST Friday...
VFR flight conditions persist across the area, but will be
quickly deteriorating as the evening progresses as a fast-
moving winter system brings snow in from the SW. Light to
moderate snow spreads from SW to NE, first impacting the
Piedmont/RIC after 00z and quickly spreading east to the
remaining sites by ~03z. Significantly reduced VSBYs/CIGs are
expected with the snow, with IFR to LIFR flying conditions
likely to begin between 02-06Z in most areas. Periods of +SN are
possible mainly between 04Z and ~09Z. A changeover to IP or
-FZRA and then RA is expected early Sat across the SE (including
ECG/ORF). Snow lingers at SBY through 12-14Z, with a mix to
rain at ORF after 11z. Dry conditions return later Saturday
morning and beyond, with VFR prevailing through the rest of the
weekend. A bit breezy Sat aftn with NW winds gusting to around
20 kt.
Outlook: Dry/VFR through the middle of next week. A dry cold
front brings another period with elevated W-NW winds Monday
night through Wednesday (generally highest across the MD eastern
shore).
&&
.MARINE...
As of 340 PM EST Friday...
Key Messages:
- Low pressure system tracks along the coast bringing rain and snow
showers across all waters. Another round of high end SCA are needed
behind the system.
- NW winds and unsettled marine conditions return late Monday night
into the middle of next week.
Winds from this morning have quickly diminished due to the
weakening pressure gradient. Wind continue to be out of the NW and
are sustained between 5 to 10 kt with gusts upwards of 15 kt across
the bay, and 10 to 15 kt with isolated gusts upwards of 20 kt across
the coastal waters. with these winds diminishing and the seas
lowering below SCA criteria all SCA have been allowed to expire.
Afternoon surface analysis shows a 1008mb low pressure system just
off the Florida coast. This system will track along the coast
bringing heavy snow and rain showers across all waters. The heaviest
of snow bands will track along the bay and rivers and could drop
visibility to less than 1/2 NM. Across the oceans visibility could
drop to less than 1 NM with the heaviest snow band. Winds overall
will remain relatively benign through this event with sustained
winds up to 10 kt and gusts up to 15 kt and some possible higher
gusts across the ocean. Once this system exists the local waters
tomorrow morning strong NW flow will return to the region ushering
colder air causing winds to increase to high end SCA criteria. SCA
have been issued for all waters starting as early as Saturday
morning and lasting through Sunday morning. Winds will be sustained
between 20 to 25 kt with gusts up to 30 kt. Some of the high res
model guidance does hint on isolated gusts upwards of 25 kt. However,
at this time no gale warnings are needed as these gusts will be very
isolated and not frequent. Conditions improve on Sunday with sub-SCA
conditions continuing into Monday as high pressure moves in from the
west. Unsettled conditions return late Monday night into the midweek
period as low pressure to the north brings another cold front across
the waters.
Seas remain between 1-2 ft across the bay and 3-4 ft across the
ocean as of this afternoon. Overall tonight, waves will remain
similar as of this afternoon. By Saturday morning behind the system
seas will again begin to build back 4-6 ft in offshore flow Saturday
into early Sunday. While across the bay waves will increase to
3-4ft.
&&
.TIDES/COASTAL FLOODING...
As of 340 PM EST Friday...
With the continuance of the NW winds this continues to allow tidal
anomalies to fall across the region. Low Water Advisories remain in
effect for the Currituck Sound and Rappahannock River through
Saturday morning. Based on real time observations and the latest
model data these tides maybe continue longer as another surge of NW
winds enter the area tomorrow morning.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...Winter Weather Advisory until 1 PM EST Saturday for MDZ021>025.
NC...Winter Weather Advisory until 1 PM EST Saturday for NCZ015>017-
030>032-102.
Winter Storm Warning until 1 PM EST Saturday for NCZ012.
Winter Storm Warning until 1 PM EST Saturday for NCZ013-014.
VA...Winter Weather Advisory until 1 PM EST Saturday for VAZ048-062-
064-075>077-098-509>511-517-519-521-522.
Winter Storm Warning until 1 PM EST Saturday for VAZ060-061-
065>069-078>090-092-093-099-100-512>516-518-520-523>525.
Winter Storm Warning until 1 PM EST Saturday for VAZ095>097.
MARINE...Small Craft Advisory from 10 AM Saturday to 10 AM EST Sunday
for ANZ630>632-634-650-652-654.
Low Water Advisory until 2 AM EST Saturday for ANZ633.
Small Craft Advisory from 7 AM Saturday to 7 AM EST Sunday for
ANZ633.
Low Water Advisory until 8 AM EST Saturday for ANZ635.
Small Craft Advisory from 10 AM Saturday to 4 AM EST Sunday
for ANZ635>637.
Small Craft Advisory from 10 AM Saturday to 7 AM EST Sunday
for ANZ638.
Small Craft Advisory from 7 AM Saturday to 10 AM EST Sunday
for ANZ656-658.
&&
$$
SYNOPSIS...RHR
NEAR TERM...KMC/JKP
SHORT TERM...KMC
LONG TERM...LKB
AVIATION...LKB/JKP
MARINE...ERI/HET
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Dodge City KS
420 PM CST Fri Jan 10 2025
.KEY MESSAGES...
- Well-below temperatures continue today despite full sunshine
and downsloping winds as fresh snow limits heating.
- Warmer tomorrow, but the next approaching weather system will
send a cold front through that could be accompanied by some
light snow.
- Gradual warming trend next week, with no noteworthy chances
for precipitation.
&&
.DISCUSSION...
Issued at 200 PM CST Fri Jan 10 2025
Water vapor satellite imagery and RAP upper air analysis at
midday reveals the highly amplified, positively-tilted trough
that brought yesterday`s snow has moved on to the Upper Midwest
through Dixie Alley, allowing DNVA to overspread the central
plains and provide us with completely clear skies. Despite the
strong solar insolation and downsloping northwesterly winds on
the northeast periphery of surface high pressure, fresh snow on
top of existing snow will significantly limit temperatures
today, with highs only in the 30s. Overnight, continued clear
skies and light winds will support ideal radiational cooling
conditions, resulting in lows dropping into the teens.
Daytime tomorrow, short range ensembles agree weak upper level
shortwave ridging will pass overhead the High Plains, which will
help foster the warmest day southwest KS has enjoyed in a while
as afternoon highs increase into the 40s for most locations.
The unlucky folks will be our far southeast zones where the
most snow fell as highs stay in the upper 30s. However, this
warmth will be short lived as a weak upper level trough digs
southeast from the Pacific Northwest towards the central plains,
and sends another cold front through our area. This frontal
passage may be accompanied by light snow during the mid-
afternoon through the evening as some high-resolution guidance
suggests, however HREF probability of snowfall reaching or
exceeding 0.5" is less than 20% for all areas, so confidence is
high any snowfall will be minimal.
Sunday through the end of the period, medium range ensembles
agree 500-mb heights atop the central plains will gradually
increase through next week as the broad, longwave trough inches
northeast, leading to a slow warming trend across our area with
little to no chances for precipitation. NBM probability of
afternoon highs at or above 50F peak in the 70-80% range for
our far southwest zones by Friday, but decrease with
northeastward extent.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 444 PM CST Fri Jan 10 2025
VFR expected through TAF pd. Some cigs may work in for KHYS at the
very end of the TAF pd as a weather disturbance starts to influence
that terminal. A fropa is expected tomorrow, but generally winds
will be fairly light as the front is expected to be weak.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...Springer
AVIATION...Sugden
Area Forecast Discussion
National Weather Service Gray ME
1057 PM EST Fri Jan 10 2025
.SYNOPSIS...
An axis of high pressure slides across the area tonight.
A clipper system brings light snow Saturday followed by another
period of high pressure Sunday into Monday. An upper low crosses
the area next Tuesday bringing renewed chances for snow showers
followed by colder air mass settling over the Northeast for the
second half of next week.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
1045 PM Update...Updated the forecast to include more clouds
across the eastern portion of the forecast area overnight as
lower clouds from the east have pushed west and now are
affecting KAUG and probably KPWM within the next couple of
hours. Otherwise, clouds will increase area-wide as cirrus
spreads overhead.
7 PM Update...Other than some increasing cirrus we expect a
quiet night with calming winds.No significant changes to the
going forecast as it remains on track. It`s so nice to not have
30 to 35 MPH gusts blasting me in the face this time of night.
Finally.
Previously...
Clear skies and narrow surface ridging this evening should allow
temps to drop quickly after dark. That will be temporary though
as clouds will invade from the southwest and thicken thru the
night. Eventually I have temps leveling off and slowly rising as
the cloud cover comes in before dawn.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
WAA will slice thru at least the southern half of the forecast
area during the first half of Sat. This will spread light snow
across parts of the region. While lift is not overly strong...it
will be more or less centered in a snow growth zone around 100
mb or so deep. This should be good enough for 15:1 ratios or
perhaps even a little better. So while QPF is light...at least
an inch appears probable for much of the forecast area. Closer
to the forcing and where it will linger longest across southern
New Hampshire...2 or 3 inches is possible.
One note is that hi-res guidance keep hinting at an inverted
trof developing and focusing a locally heavier band of snow
during the day Sat. At this time it is really just the HRRR that
has it affecting the forecast area...but other hi-res guidance
is nearby around Cape Ann. The good news is that the trof is
fairly transient...forming and then sweeping south as the storm
enters the open ocean. It will still bear watching...as it could
lead to an additional inch or two if it does manage to
develop along the Seacoast. I did nudge both PoP and QPF there
to at least hint in this direction.
Sat night precip will have transition to upslope snow showers.
Much like this past upslope event...flow looks to be quite
blocked. Snow showers should therefore be confined to areas
upstream of the mtns. Temps will be a steady decline thru the
night in CAA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
1045 PM Update...New NBM is in and differs little with the rest
of the guidance in the extended. Mainly dry weather continues to
be expected but we may need to increase PoPs some late Mon-Tue
with vigorous upper trough expected to amplify overhead.
Previously...
A ridge of high pressure will build into the forecast area Sunday
and will slide offshore Monday. This will bring a period of fair
weather with temperatures running above normal. An upper low will
cross the area Tuesday into Wednesday bringing chances for snow
showers. A colder air mass will move into northern New England
behind this system with a period of gusty NW winds. The second half
of next week looks mostly dry with temperatures trending below
normal.
High pressure cresting over the area Sunday afternoon will allow
for mostly sunny skies and light winds. Highs on Sunday will
range from the mid 20s north the mid 30s south. Conditions
remain mostly dry Monday with increasing clouds as the ridge of
high pressure moves offshore. Light SW flow will brings highs on
Monday a couple of degrees higher than Sunday.
An upper low will cross the area Tuesday through Tuesday night.
The 12Z model suite suggests there will be little in the way of
surface features to focus precipitation resulting in mainly
scattered snow showers. A shot of colder air will move in from
Canada Wednesday into Thursday. Additional disturbances in NW
flow aloft suggest at least the mountains could see additional
snow showers through the end of next week while there is limited
signal for a widespread precipitation event.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
Short Term...Widespread VFR tonight. Light snow will be moving
in near or shortly after daybreak Sat. Areas of IFR conditions
will move thru the area during the day Sat...gradually improving
to VFR during the afternoon or evening south of the mtns.
Additional upslope cloud cover and snow showers will be possible
around HIE with local MVFR or lower conditions.
Long Term...Mainly VFR through the period. Snow showers on
Tuesday will likely be more persistent A KHIE that could bring
periods of restrictions.
&&
.MARINE...
Short Term...Winds and seas continue to diminish this evening. I
have trimmed the SCA from the coastal waters of Casco Bay and
south of Cape Elizabeth for the overnight. The break in gusty
winds will be brief. After light snow moves thru Sat...northeast
winds will pick up and SCA conditions are likely outside of the
bays. A new SCA will likely be needed after the current one
expires.
Long Term...North winds will relax Sunday as high pressure
builds in from the west. Winds and seas likely remain below SCA
thresholds Sunday afternoon through Tuesday. Increasing NW winds
will likely bring SCA conditions by Wednesday.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.
&&
$$
NEAR TERM...Ekster/Legro
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1029 PM EST Fri Jan 10 2025
.KEY MESSAGES...
- An accumulating snowfall event of significance continues to
affect the region this evening and tonight, before tapering off
late tonight to Saturday morning.
- The heavier accumulations from this event are still expected
over the more southern and southwestern locations.
- Below normal temperatures will persist through the next week.
&&
.UPDATE...
Issued at 1028 PM EST FRI JAN 10 2025
Made adjustments to PoPs through 18z Saturday utilizing a mix of
the 18z GFS, 00z NAMNest, and NBM, mainly to better reflect
current radar trends as well as projected cold advection snow
showers and flurries during the day Saturday. Other changes were
insignificant.
UPDATE Issued at 651 PM EST FRI JAN 10 2025
The forecast is largely on track, but still made some minor
changes to the grids to account for latest model trends. The
Winter Storm Warning statement was updated with the latest
additional forecast accumulations starting at 7 PM EST.
&&
.SHORT TERM...(This evening through Saturday night)
Issued at 455 PM EST FRI JAN 10 2025
Late this afternoon, an upper level trough extended from Hudson Bay
to the western Great Lakes to mid MS Valley to the Southern Plains,
upper level ridging extending from the Pacific across portions of
the southwestern Conus to WY to the western Dakotas, and another
trough upstream from western Canada into the Pacific Northwest. At
the surface an area of low pressure was tracking across the
northeast Gulf of Mexico with an inverted trough extending into the
TN Valley and Appalachians. Another clipper type system was tracking
across the western Great Lakes with a cold front extending into the
upper MS Valley. Meanwhile a ridge of high pressure extended from
the Rio Grande Valley northeast to parts of the Central Plains. Snow
was falling across much of the TN Valley into the oH valley and
Southern Appalachians at this time with varying intensity. Some
transient heavier bands have affected portions of the region from
midday through this afternoon with a couple of more sustained bands
from OH to the Louisville area to the Fort Campbell vicinity and t
another that has been working northeast form middle TN toward the
Cumberland Plateau and Lake Cumberland region. Locally, snowfall
intensity has picked up across the northwest and western sections of
the area over the past half of an hour.
This evening and tonight, the peak of the event should occur as the
upper level trough axis approaches with the lead shortwave trough
crossing the Lower OH Valley this evening which should lead to an
increase in intensity of the snow areawide. Some bands of heavier
snow may occur with potentially the deformation band working into
the western and northwestern sections this evening while the band
snow over TN may work across the southern and southeastern counties
with some HRRR picking up on this. This should lead to the heaviest
storm total snow this evening and tonight across counties south of
the Mtn Pkwy and perhaps south of the Hal Rogers Parkway and KY 80
corridor. There remains some uncertainty in the more northern
counties as far as reaching the 4 inch warning criteria versus
staying more on the upper end of advisory criteria in the 2 to 3
inch range. Although the 12Z HREF and guidance has lower
probabilties or forecasts of rates less than an inch per hour rates
of 0.5 inches per hour or more may occur for a few hours in the
heavier bands. This steadier activity should begin to wind down from
west to east by the overnight hours as the lead shortwave crosses
the area and the sfc low tracks toward the Carolinas. However, cold
advection and linger moisture along with somewhat of an upslope
component will lead to lingering snow showers and flurries once the
steadier snow winds down. Over the counties near the VA border, the
steadier snow may hang on a bit longer into the day on Saturday. At
this point even though the banded nature of the snow may lead to
some areas/counties falling short of warning criteria, no changes to
headlines were made at this time as the height of the event will be
over the next few hours.
On Saturday, the initial shortwave trough axis is expected to shift
east of the area during the morning with shortwave ridging/height
rises across the region behind that. This shortwave ridge works east
across the area on Saturday night in advance of the next trough
sharpening from Manitoba south through the Plains/Central Conus. At
the surface, low pressure slides northeast off the NC coast and into
the Atlantic with sfc high pressure ridge building north northeast
into the Lower OH Valley/Commonwealth Saturday and then settles from
the Central Appalachians to the northeast Gulf of Mexico Saturday
night. 850 mb temperatures will continue to fall behind the
departing system on Saturday and bottom out at roughly -9C to -11C
from midday to early afternoon on Saturday. Moisture should extend
to at least the -10C level throughout the day and this combined with
the cold air advection and daytime heating leading to instability and
westerly flow with an upslope component should lead to snow showers
lingering until nearly midday in the southeast with flurries
areawide behind the steadier snow. Under the cold advective pattern,
temperatures should only rise a few degrees on Saturday with most
places struggling to get to the 30 to 32 degree range. Clouds should
gradually thin from the south on Saturday night with temperatures
likely to fall into the teens.
.LONG TERM...(Sunday through Friday)
Issued at 548 PM EST FRI JAN 10 2025
Our New England-like winter pattern rolls on through the long-term.
The latest 10/12z model suite analysis beginning Friday morning
shows ridging from the southern Appalachians northward into
Ontario. Meanwhile, a deep positively-tilted trough stretches from
an ~515 dam low over Manitoba southwestward to over the Baja
California. Translating down to the surface, this is reflected by
a surface high along the Central and Southern Appalachians with
upstream ~1004 mb low pressure over the Upper Midwest. One cold
front extends southward from this low to over Texas while a second
arctic boundary curves back to the northwest along the eastern
slopes of the Canadian Rockies.
A relatively mild southwesterly return flow setup across eastern
Kentucky on Sunday as the high pressure moves off to the east.
This will bring us a brief thaw for Sunday as temperatures warm
into the mid 30s north to the lower 40s south of the Mountain
Parkway (at lower elevations). Skies should remain clear enough
Sunday night for the development of a ridge-valley temperature
split in the upper 10s to mid 20s. The aforementioned surface low
will move north of Sault Ste Marie Sunday night dragging the first
cold front through eastern Kentucky early Monday morning,
bringing a few snow showers. A few snow showers and flurries can
be expected to continue through Monday with the approach and
passage of the second cold front. In the wake of the second cold
front, deep/broad 500H troughing will become re-established over
the Northeastern CONUS/Great Lakes/Ohio Valley.
Multiple weak disturbances rotating around trough will keep flurries
and occasional snow showers lingering through Wednesday. Any
accumulations appear minor at this point. Temperatures are also
forecast to once again dive into the freezer mid-week. After one
more day with maximum temperatures in the 30s on Monday, expect
highs only in the upper 10s to mid 20s for Tuesday and Wednesday
with nighttime lows in the single digits to 10s. Some of the
coldest spots could flirt with or drop below 0F, most likely on
Tuesday night. The mean troughing finally begins to pull away on
Thursday and Friday, allowing a milder westerly flow to return and
send daily maximum temperatures back closer to the freezing mark
on Thursday and perhaps even nearing 40 or better for some
locations on Friday. This second thaw doesn`t look to last though
as longer range CPC outlooks highlight elevated probabilities for
much below normal temperatures returning after January 20th.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
ISSUED AT 621 PM EST FRI JAN 10 2025
Widespread snow with a winter storm is bringing generally IFR,
LIFR, or VLIFR conditions this evening. Worst conditions should
occur through the first 6 hours of the TAF period with slowly
improving cigs into IFR for most locations through about 15Z,
before improvements from west to east into the MVFR range as snow
slowly tapers off. Generally light winds less than 5 kts will
becoming south and then west through 09Z, then remain from the
west through the end of the period at 5 to 10 kts through much of
the remainder of the TAF period before diminishing toward 23z
Saturday.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 1 PM EST Saturday for KYZ044-050>052-
060-104-106-107-109-110-119-120.
Winter Storm Warning until 10 AM EST Saturday for KYZ058-059-068-
069-079-080-083>088-108-111>118.
&&
$$
UPDATE...CMC
SHORT TERM...JP
LONG TERM...GEERTSON
AVIATION...CMC
Area Forecast Discussion
National Weather Service Raleigh NC
938 PM EST Fri Jan 10 2025
.SYNOPSIS...
Arctic high pressure will settle into the lower Middle Atlantic
today. An area of low pressure will track northeast from the Gulf
coast today to the North Carolina coast tonight, and then offshore
on Saturday. High pressure will build back in through Sunday.
&&
.NEAR TERM /REST OF TONIGHT/...
As of 938 PM Friday...
* Winter Storm Warning and Winter Weather Advisory remains in effect
for central North Carolina through Saturday morning.
No changes are planned to current Warning and Advisory areas.
The warm air aloft, which was highly evident in dual-pol CC data,
has surged north across much of the area. The snow has already
changed over to sleet across the central and northern portions of
the Piedmont, which will greatly limit additional snow/sleet going
forward. So far we`ve seen a maximum of 1-1.5" across the northwest
and northern Piedmont, with 0.5-1.0" around the Triangle. RAP
soundings show that the warm nose over the NW Piedmont could
collapse back to the east and south, which could allow for
additional 0.5-.1.0" of snow/sleet before drying out aloft and
precip tapers as freezing rain/drizzle between 09 to 12z.
The main concern for the remainder of the event is the transition to
freezing rain, which is rapidly lifting northward into central
portion of the forecast area. It still appears a corridor of 0.1-
0.2" of freezing rain is likely across south and east of the I-85
corridor, with some isolated higher amounts of 0.25" possible. The
cessation of the wintry precip is still on track to exit the area
around sunrise.
Previous discussion: Minor to moderate impacts are expected across a
majority of central North Carolina, with locally significant impacts
possible. However, there is still some uncertainty with regard to
the exact accumulations at any given location...more below.
As of 3 PM, the surface low was located over the western panhandle
of FL, while generally high pressure lingers over the Carolina
coast. Snow, sleet, and rain have started to fall across western and
southern portions of central NC, and is expected to spread nnewd
over the area through this evening. Where precipitation has been
falling for an hour or so, temperatures have fallen into the
mid/upper 20s, a trend that should continue over the next several
hours. The surface low should continue ewd along the FL panhandle
for the next couple hours, then lift newd through FL/GA before
tracking along the Carolina coast tonight. As the low approaches,
the warm nose aloft will strengthen, especially in the southeast.
The low should begin to move enewd away from the NC coast Sat
morning.
Snow: Given the multiple days of very cold conditions, the ground is
sufficiently cold to allow for efficient and immediate accumulation
of snow. This will be very atypical compared to a normal "Carolina`s
winter event" where it would take a couple hours for accumulation to
begin. Along and north of the I-85 corridor is most likely to remain
mostly snow and sleet with accumulations of generally 2 to 4 inches
expected. Locally higher amounts will certainly be possible,
especially where it remains all snow for the duration of the event.
Freezing rain: Forecast confidence remains lowest with the freezing
rain accumulations and location of greatest impacts. A majority of
guidance has a swath of ice accumulations developing after midnight,
as surface temperatures drop to below freezing in the insitu CAD
regime that sets up at precipitation onset, however vary on its
placement. Many model solutions show a narrow swath of freezing rain
accumulation around 0.25", decreasing sharply outward from the
swath. Even if that does not materialize, a swath of 0.1" to 0.2" is
probable, which would still be impactful. The uncertainty is where
exactly that swath will be. Latest best guess is along a line from
Wadesboro to Lillington to Rocky Mount. Where this forecast may go
wrong is if the insitu wedge doesn`t hold over the southern
Piedmont, Sandhills, southern Piedmont and the central/southern
Coastal Plain and southerly flow and gradual warming above freezing
at the surface occurs, which would significantly narrow/lessen the
freezing rain accumulations as a transition to all rain occurs.
Sleet: In between the snow and freezing rain corridors will likely
be a transition to mainly sleet for an hour or two, but may remain
stationary for several hours as the warm nose ceases to spread
farther north. Sleet accumulations of 0.25" to 0.5" are possible if
it persists for more than an hour or two in any given location. This
is most likely to occur perhaps along and just south of the I-85
corridor into the Triangle, which would cut snowfall totals closer
to the 0.5" to around 2" range.
By Saturday morning, precipitation will likely rapidly come to an
end in the Triad by 4-6 AM, the Triangle by 5-7 AM, and exiting the
Coastal Plain by 8 AM.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 340 PM Friday...
All precipitation should exit to our east after 12z Saturday, with
skies becoming mostly clear behind the departing mid/upper trough
and associated surface low that will be moving off the NC coast. The
pressure gradient between the deepening low moving NE into the
Atlantic and a building high over the Deep South will result in NW
winds around 10-15 mph with gusts to 20-30 mph from mid-morning into
the afternoon, highest east. The full sunshine will help
temperatures rise above freezing everywhere by mid-to-late-morning,
reaching a high in the lower-to-mid-40s in the afternoon. This will
help melt the snow and ice that had accumulated, especially on the
roads and less so in shady spots. While travel impacts will lessen
through the day, the gusty winds may help bring down more trees and
tree branches already weighed down by the snow and particularly ice,
resulting in a threat for additional power outages.
The surface high will reach the Appalachians on Saturday night. Low-
level thicknesses bottoming out in the 1280-1290 m range combined
with clear skies, light winds and lingering snow cover will bring
low temperatures down into the upper-teens to lower-20s. This will
quickly freeze any lingering moisture on the roads, resulting in
some black ice concerns. However, the extent of black ice will
depend on how much moisture is able to evaporate during the day
Saturday from the sunshine and gusty NW winds.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY...
As of 315 PM Friday...
Wnwly flow aloft Sunday morning will turn a bit more swly in the
evening as a southern stream wave moves across the Gulf of Mexico.
As we pivot to early to middle of next week, a trough over the Great
Lakes will dive south a drive dry and colder air into the southeast.
Ensembles/deterministic runs are in good agreement shunting the
anomalous moisture associated with the Gulf of Mexico system to our
south. As such, we continue to highlight a dry forecast in the
extended range.
Temperature wise, after daytime highs generally in the mid 40s
Sunday and Monday, the cold air mass will plummet temperatures back
into the mid to upper 30s by Wednesday. Temperatures will moderate a
bit by Friday. Overnight lows Tuesday and Wednesday nights could be
quite cold, potentially dipping into the mid to upper teens.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As of 640 PM Friday...
TAF period: Precipitation continues to spread from west to east.
Flight conditions are highly variable as of 23Z, with IFR conditions
at INT/GSO and VFR conditions at FAY/RWI, but LIFR ceilings are
expected at all sites by 06Z. Precipitation will be primarily snow
at INT/GSO, while RDU/RWI/FAY should begin as a snow/sleet mix and
eventually transition to freezing rain. Precipitation should come to
an end at all terminals by mid-morning Saturday, and as low pressure
moves off the coast, expect NW winds 10g20kt to develop across all
sites.
Outlook: Dry VFR conditions are forecast through the outlook period.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 1 PM Friday to 10 AM EST Saturday for
NCZ007>011-021>028-038>043-073>077-083>086.
Winter Weather Advisory from 1 PM Friday to 10 AM EST Saturday for
NCZ078-088-089.
&&
$$
SYNOPSIS...BLS
NEAR TERM...CBL/KC/Swiggett
SHORT TERM...Danco
LONG TERM...Luchetti
AVIATION...Green