Winter Weather Update

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Hazardous Weather Outlook
National Weather Service Jackson KY
402 AM EST Mon Dec 30 2024

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402 AM EST Mon Dec 30 2024

This Hazardous Weather Outlook is for a portion of eastern Kentucky.

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

South to southwest wind gusts of 25 to 35 mph are expected at most
locations on Tuesday, except above 2,000 feet where locally stronger
wind gusts of 40 to 50 mph are possible.

A mix of wintery precipitation is possible on Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

$$

GEERTSON/MARCUS

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AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
221 PM EST Mon Dec 30 2024

.KEY MESSAGES...

- Well above normal temperatures will last through Tuesday,
followed by a return to winter cold to start the new year.

- Quick-moving low pressure will bring another round of rainfall
on Tuesday along with strong south to southwest winds gusting to
between 25 and 35 mph at most locations.

- A dynamic storm system may bring a mix of wintery precipitation
types to Eastern Kentucky next Sunday.

&&

.UPDATE...
Issued at 221 PM EST MON DEC 30 2024

Light precip returns have diminished across the area, with clouds
gradually thinning out with time as expected. Made some minor
adjustments to the high temperatures, based on the latest trends
in the observations. Otherwise, the forecast remains on track.
Updates have been sent.

UPDATE Issued at 1113 AM EST MON DEC 30 2024

The forecast remains on track this morning. Mostly cloudy skies
continue to hold in across the majority of the area; however,
satellite trends reveal some diminishment on the northern and
southern periphery of the main canopy. A few light returns remain
evident on radar, more coincident with a weak surface trough. As
modest short wave ridging takes holds through the day, moisture
should become more shallow, and expect the sprinkles to gradually
dry up, and clouds to relent somewhat. Forecast highs in the mid
50s for most locations are also on target. Merely freshened up the
hourly temperatures and dew points through the afternoon,
accounting for an overall slightly cooler trend late this morning.
Updates have been sent.

UPDATE Issued at 821 AM EST MON DEC 30 2024

Radar shows last shower moving from Pike County into southwest
Virginia. Some river valley fog has developed where skies have
cleared sufficiently, especially in the upper reaches of the
Cumberland River basin. Any fog should lift by ~10 AM but
anticipate that low clouds will fill back in for a time later this
morning and could produce a few sprinkles into the early
afternoon hours.

&&

.SHORT TERM...(Today through Tuesday)
Issued at 517 AM EST MON DEC 30 2024

A much quieter day is ahead as any leftover showers are
dissipating/exiting the area early this morning. Low clouds remain
widespread for now. Temperatures are also noticeably cooler than
yesterday in the lower to middle 40s -- still about 15 to 20 degrees
above normal lows for this time of year. The latest analysis shows
the low pressure responsible for yesterday`s rain and wind now
centered over Lower Ontario. The associated cold front extends
from the low southeastward to off the New Jersey coast and then
south and southwestward across the Florida Peninsula. Surface
high pressure ridging extends from the Upper Midwest to the Lower
Mississippi Valley. Further west, another low pressure system is
taking shape in the lee of the Central Rockies.

Conditions over the Eastern Kentucky Coalfields will slowly dry out
today as the low pressure system to our north lifts into Quebec and
the high pressure ridging translates eastward to over the Lower
Ohio Valley. Meanwhile, the next low pressure system will begin
trekking eastward through the Central Plains, reaching Missouri
this evening. This low passes through Illinois tonight before
riding north of the Ohio River during the day on Tuesday. This low
is forecast to have a robust wind field with 850 mb winds nearing
or exceeding 50 knots as the low`s warm front passes from west-
to-east over the Coalfields on Tuesday morning. Though not as
evident in some of the other guidance, recent RAP model soundings
along the warm front reveal an intriguing shallow CAPE profile
(equilibrium levels generally warmer than -20C) of up to ~500
J/kg of SBCAPE with minimal CIN. This instability combined with
between 30 and 40 knots of effective shear and 100 to 250 m^2/s^2
of 0-to-1 km of storm relative helicity is sufficient for
supercellular showers along the warm front. Later shifts will need
to continue assessing the potential for strong winds with this
convective activity. Otherwise, the system`s cold front will
quickly follow closely on the heels of the warm front, likely
exiting to east around or shortly after midday. Post-frontal winds
in the low`s dry slot will again become strong with BUFKIT mixed
layer momentum transfer supporting 20 to 30 kt gusts across the
area with the strongest winds generally closer to the Virginia and
Tennessee borders. Locally stronger winds are possible above
2,000 feet during the morning when the 40 to 50 knot low-level jet
is most likely to impinge upon the terrain. Eventually, comma-
head moisture will wrap back into the eastern Kentucky Tuesday
afternoon as the low and stronger low-level winds depart to our
east.

In sensible terms, look for any showers to diminish to a few
sprinkles for the remainder of the morning. The low clouds will be
slow to break but should eventually attempt do so from south to
north. It will be cooler with highs only in the mid 50s at most
locales. Temperatures are expected to dip after sunset this
evening, perhaps even allowing for the formation of a modest
ridge-valley temperature split east of the Escarpment. Forecast
lows range in the upper 30s through the coolest northeastern
hollows and in the lower to middle 40s elsewhere. Minimum
temperatures are likely to be established early in the night as
winds will tend to pickup and clouds increase as the next storm
system approaches. Shower chances rise from the west to east after
1 AM EST and peak Tuesday morning with the passage of the warm
front and again during the midday/afternoon hours with the passage
of the cold front. South to southwesterly winds will become
strong Tuesday morning, generally gusting 25 to 35 mph at most
locations. However, locally stronger gusts in the 40 to 50 mph
range cannot be ruled out over the higher elevations above ~2000
feet. Temperatures will be mild, mainly in the mid 50s early in
the day before falling into the 40s during the afternoon. Event
total rainfall should be light, generally less than one quarter
inch.

.LONG TERM...(Tuesday night through Sunday)
Issued at 553 AM EST Mon Dec 30 2024

The long term forecast period opens upon a wet New Year`s Eve
forecast. A fast-moving and vertically-stacked low pressure system
will eject out of the Ohio River Valley and into New England by New
Year`s Day, but some wraparound moisture will stick around the
region to kick off 2025. While there has been a noticeable drying
trend in the modeled lower atmospheric moisture content for
Wednesday, some [slight] chance PoPs remain in the forecast. On the
backside of this system, cold air begins to advect into the area,
which may allow the leftover rain showers from New Year`s Eve to mix
with snow as precipitation tapers off. This changeover appears most
likely in areas of higher terrain, but the antecedent warmth will
severely limit accumulation potential and thus reduce the risk of
travel impacts. Temperatures on New Year`s Eve will be in the mid
30s across most of the area, and then they will struggle to surpass
the upper 30s on New Year`s Day with cloudy skies and the
aforementioned cold air advection in the forecast.

On Wednesday night into Thursday, surface high pressure will build
into the region and foster a clearing trend. While the sensible
weather looks drier during this time frame, it also looks much
cooler. Expect late week highs in the upper 30s to near 40, with
lows dipping into the 20s. Guidance continues to resolve a clipper-
type system quickly passing through our forecast area on Thursday
Night into Friday, and with the colder air in place, this system
could produce some snow. However, the various members of the
forecast guidance suite disagree on the amount of moisture that this
system will have to work with, which in turn will determine the
efficacy of this snow. The greatest potential for accumulating snow
currently looks to be in the higher terrain along the Virginia state
line and in locations northeast of the KY-15 corridor. For the
former, a forecast shift to northwesterly flow as the system
progresses will lead to orographic lifting enhancements on northward
facing slopes. For the latter, there is a greater signal for
sufficient moisture in the guidance in this area. Regardless, the
quick forward speed of the parent system should relegate
accumulations to less than half an inch.

As said system departs, a reinforcing shot of cold air will advect
into the area via northwesterly flow on Saturday. With morning lows
split between the upper teens (valleys) and lower 20s (ridgetops),
and afternoon highs forecast to hover around freezing, this colder
airmass will prime the area for potential wintery precipitation on
Sunday. Confidence has increased that a dynamic storm system will
approach the Ohio River Valley late next weekend, and the
precipitation out ahead of it is likely to start as snow on Sunday
morning given forecast lows in the upper teens that morning. Beyond
then, a variety of precipitation types are on the table. The latest
deterministic runs of the GFS and European models are closer to a
consensus than they were at this time yesterday, but there remains a
great deal of model spread in the temperature forecast for Sunday.
For example, the difference between the 25th and 75th percentiles of
the NBM is approximately 15 degrees for Sunday, with the majority of
the members resolving afternoon highs above freezing. Collectively,
these pieces of forecast guidance suggest that a warm front will
lift north across the area at some point on Sunday, with warm air
nosing into the mid levels via isentropic upglide. This would yield
in a messy precipitation type forecast in which the exact details of
the parent low pressure system`s positioning and forward progression
speed will determine what p-type falls where, when, and for how
long. It is far too early to pinpoint such details, so for now, the
forecast grids depict a snow/rain mix on Sunday.

Beyond then, model spread remains too high to provide sensible
weather specifics, but long range guidance suggests a
climatologically colder-than-normal first full week of January. The
latest Climate Prediction Center 8-14 Day Outlook signals an 80-90%
chance of below normal temperatures. To contextualize this, the
normal temperatures for Eastern Kentucky in early January are
defined as MaxTs in the lower 40s and MinTs in the upper 20s.
Interested parties are encouraged to stay tuned to future forecast
packages as the details regarding this weekend`s system come into
focus, especially if they have post-holiday weekend travel plans.
They are also encouraged to visit weather.gov/safety/winter to learn
more about how to prepare for the aforementioned winter weather and
cold temperatures ahead of time.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 100 PM EST MON DEC 30 2024

MVFR ceilings will diminish from the south and the north through
20z, with VFR conditions returning and holding through late
tonight. Clouds will lower once again from the west during the
pre-dawn hours, as deeper low pressure tracks east into the Ohio
Valley. Showers will develop and move in by around 09z, and some
of these have the potential to bring temporary MVFR conditions.
Showers will continue through the day, with ceilings lowering to
MVFR from the west, behind a departing cold front. Southwest winds
of around 5 kts, will diminish and back to the southeast through
this evening. Meanwhile, a strengthening low jet will provide a
threat of LLWS overnight into early Tuesday morning, before more
turbulent mixing ensues, as low pressure draws closer to our area.
Surface winds will increase to 10 to 15 kts, with gusts of 25 to
30 kts out of the south southwest.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JKL
SHORT TERM...GEERTSON
LONG TERM...MARCUS
AVIATION...JKL