Jinks, Kentucky Weather Forecast Discussion

545
FXUS63 KJKL 201836
AFDJKL
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
236 PM EDT Sat Sep 20 2025
.KEY MESSAGES...
- The probability for showers and thunderstorms increases each day
  into early next week.
- A Marginal Risk for a severe storm or two exists for Sunday
  afternoon and evening across western parts of northeastern and
  eastern Kentucky.
- Widespread, beneficial rainfall is possible next week, which
  would help to ease ongoing dry conditions across much of eastern
  Kentucky.
- There is a possibility for strong thunderstorms on Thursday,
  but significant uncertainty remains with the parent storm
  system`s track and strength.
&&
.SHORT TERM...(This evening through Sunday night)
Issued at 235 PM EDT SAT SEP 20 2025
A longwave trough remains across the north-central US, with a
negatively-tilted shortwave bringing today`s convective activity
before moving northeast and away from the area tonight. The
longwave trough takes on a positive tilt Sunday into Sunday night,
allowing for increase southwesterly upper flow across the region,
thus increasing warm advection across the Ohio Valley, including
eastern Kentucky. The associated disturbances moving through this
southwesterly flow will be triggers for the associated showers and
storms over the region Sunday and into early next week.
An upper tropospheric disturbance combined with sufficient moisture
and instability will allow for continued shower and isolated
thunderstorm development this afternoon, but the better upper-level
support will move out of the area to the northeast by mid- to late
evening, and surface instability will also wane with the loss of
daytime heating. Skies should clear as drier air moves over the area
and warm advection weakens considerably despite continued southerly
low-level flow. This will allow for fog formation in the typically-
prone river valleys, and may be locally dense especially where skies
are clear and where it rained this afternoon.
Warm advection increases again through the morning Sunday ahead of
an approaching disturbance, with moisture and instability
increasing. Wind shear will also increase by early afternoon ahead
of a subtle disturbance passing ahead of the primary disturbance
back to the west, and this may be just enough to support the threat
for a stronger storm or two. For this reason, the SPC has issued a
Marginal Risk for severe storms for northern and parts of central
and east Kentucky. The best wind shear arrives Sunday evening into
the overnight, but by that time the atmosphere is most likely worked
over from expected afternoon activity. However, at least isolated
showers and possibly a few storms can be expected into the
overnight Sunday night with warm advection continuing. During this
time, highs will continue to moderate downward closer to normal
while lows trend upwards with lesser ridge-valley splits than what
we have become accustomed to in the last few weeks of drier
weather.
.LONG TERM...(Sunday night through Friday)
Issued at 525 AM EDT SAT SEP 20 2025
Again, the main changes to the extended forecast on this shift
were to slightly enhance the terrain based differences for
temperatures each night. The PoP chances are looking more
promising for the new work week with even some excessive rains
possible by mid week.
The previous long term discussion follows:
The forecast period begins Sunday morning with a positively-
tilted 500 mb trough extending from Northern Ontario into the
Central Plains. Ridging is departing via the Mid-Atlantic and New
England as multiple disturbances eject from the Southern/Central
Plains toward the Ohio Valley. One of those disturbances will be
lifting into the Lower Ohio Valley Sunday morning, accompanied by
strong low-level warm air and moisture advection. The strongest
modeled forcing initially favors the western half of the forecast
area, where isolated showers and thunderstorms could be ongoing at
the start of the forecast period.
Model agreement is good for the first few days of the long-term
before spread becomes significant during the second half of the
forecast period. At this point, focus is on any notable large-
scale synoptic pattern agreement that is favored by ensembles such
as the 100-member LREF. An analysis of the latest data favors a
broadening 500H trough over the Central and into the northern
CONUS on Monday as the parent upper-level trough dampens and pulls
away to the northeast. Additional energy traverses the Rockies
and begins digging into the large-scale trough by Tuesday.
A majority (~68%) of the 00z LREF guidance showed that energy
diving into the Central Plains on Tuesday, though there were
substantial differences in eastward progression. At least half of
the 100-LREF members then favor that energy leading to the
formation of a closed low near or over Missouri on Wednesday.
Other solutions, however, favor a more subtle open wave. An even
larger number of members have that closed low feature on Thursday
in the vicinity of the mid-Mississippi Valley, though a
significant minority ~25% still favor a more progressive open
trough. In the favored majority solution, the upper low generally
drifts into the lower Ohio Valley region on Friday but could begin
to fill and/or begin the transition to an open wave as it
meanders closer to the stronger westerlies over southern Canada.
The synoptic-scale setup favors a surge of moisture moving in Sunday
into Monday as the trough initially to our northwest dampens and
pulls away. While the stronger upper-level forcing remains to the
north, PWATs are forecast to rise into the 1.3 to 1.6-inch range.
This renewed moisture, combined with surface heating and a
passing upper-level disturbance, will support modest instability
(>500 J/kg) on Sunday; however, weak shear will limit convective
vigor. That moisture lingers through mid-week with additional
passing weak perturbations aloft. The resulting diurnally-
modulated convection will maintain likely (40-60%) rain chances
for Monday through Wednesday. More substantial forcing is likely
to attend the upper low later in the week. Of particular interest,
at this point, is Thursday, which depending upon the track of the
upper low could bring a combination of shear and instability more
favorable for organized strong to perhaps severe thunderstorms as
eastern Kentucky potentially ends up under a strong warm conveyor
belt jet ahead of the systems cold front. While the associated
surface low is still favored to remain north of the Ohio River, a
strong cold front wrapping clockwise around the increasingly
vertically stacked low would then be favored to bring cooler and
perhaps continued showery weather to eastern Kentucky by Friday.
With abnormally dry to drought conditions ongoing across the
Commonwealth, the chances of a much-needed wetting rainfall appear
increasingly likely. The probability of at least 1 inch of
rainfall through Friday ranges from 50% in the far east to nearly
70% west of the Pottsville Escarpment.
In terms of sensible weather, Sunday will be another very warm
day with a mix of sun and clouds and highs in the mid-80s. A
chance of showers and thunderstorms exists, especially over
western portions of the area, though isolated activity is possible
anywhere. Scattered shower and thunderstorm chances will continue
each day from Monday through Wednesday. High temperatures will
gradually fall to around 80F by Wednesday. With more widespread
rain chances on Thursday and possibly Friday, forecast high
temperatures will fall further into the 70s. Nighttime low
temperatures remain in the mid 50s to mid 60s through Wednesday
night before settling back mainly into the 50s late in the week.
Fog is likely in the favored valleys each night and could be more
extensive in locations that receive substantial rainfall.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 136 PM EDT SAT SEP 20 2025
A cluster of showers with a few embedded thunderstorms extends
along a north-south line between KJKL and KSJS, and this activity
looks to continue for the next several hours. Will carry VCTS at
KJKL and KSJS, with a TEMPO group for -TSRA at KSJS, with the
potential for locally gusty winds/outflows briefly reaching these
two terminals. Otherwise, isolated to widely scattered showers
and storms can be expected this afternoon. Skies clear this
evening, which should promote fog development in the river
valleys, dissipating ~13z-14z Sunday. More showers and storms will
arrive Sunday afternoon, and will be more widespread than today,
but confidence is too low to include in the TAFs this far out
given uncertainties with timing. Winds outside of showers and
storms will be light and variable, becoming light out of the
south and southwest at 5 to 10 kts late in the period (~16z
Sunday) ahead of an approaching disturbance.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...CMC
LONG TERM...GEERTSON/GREIF
AVIATION...CMC

NWS JKL Office Area Forecast Discussion