057
FXUS63 KJKL 131914
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
314 PM EDT Thu Aug 13 2026

.KEY MESSAGES...

- The potential for showers and thunderstorms will persist through
  the end of the week. The greatest coverage is expected through
  tonight. Some of the storms could arrive as organized clusters
  with a possibility for strong to damaging wind gusts.

- Excessive rainfall may occur where storms are most persistent,
  leading to flash flooding.

- A Flood Watch is now in effect for the northeast portion of the
  forecast area through 8 AM EDT Friday morning.

&&

.UPDATE...
Issued at 1055 AM EDT THU AUG 13 2026

14Z sfc analysis shows a wavy front has shifted east deeper into
eastern Kentucky. Some widely scattered storms are working east
ahead of this boundary and still could cause some localized heavy
rain. The afternoon conditions are still a bit muddled but seems
to be trending down. Have adjusted the CAMs PoPs into the evening
with lesser values west of that boundary as it shifts further
east. Currently, temperatures are warming much quicker than
yesterday with reading reaching the upper 70s to lower 80s in the
west and still in the low to mid 70s where the showers or storms
have recently gone through. Meanwhile, amid still rather light
winds, dewpoints are generally in the sticky lower 70s. Have
updated the forecast mainly to add in the latest radar and CAMs
trends for PoPs. Did also add in the obs and tendencies for the
T/Td/Sky grids. These minor adjustments have been sent to the NDFD
and web servers along with a freshening of the SAFs and zones.

UPDATE Issued at 910 AM EDT THU AUG 13 2026

Adjustments to PoPs and QPF were made for the near term with
flooding likely in northern Letcher County as a thunderstorm only
slowly dragged its way out of the CWA. Also, with the best
consensus high resolution forecasts keeping much of the area dry
through the afternoon could not justify extending the watch for
most of the area. Did extend the northeast section where we have
the highest QPF forecast for the next 24 hours and there is a
better chance them to be impacted by additional MCS. In addition
to those changes, did also include the latest obs and trends for
the T/Td/Sky grids. These adjustments have been sent to the NDFD
and web servers along with a freshening of the FFA, HWO, SAFs and
zones.

&&

.SHORT TERM...(Today through Friday)
Issued at 445 AM EDT THU AUG 13 2026

08Z sfc analysis shows a nearly stationary boundary arcing west to
east over Kentucky passing through the western Cumberland Valley.
This keeps eastern Kentucky in a prime location for organized
clusters of showers and thunderstorms to periodically develop
and move southeast through the region. These will bring times of
heavy rain and a potential for strong wind gusts. The latest of
these is rather steady state in strength as it is spreading
just south of east through the middle parts of the JKL CWA after
entering in Estill County. A few Flood Advisories have been
issued due to its slow movement and heavy rains over already
soaked locations. Luckily, it appears to be progressive enough to
prevent any more than minor and nuisance flooding. However, this
area will be ripe for flash flooding should a subsequent cluster
hit it later this morning or in the afternoon. Otherwise, clouds
from the earlier cluster have cleared but the new one is spreading
back in and this should make any fog issues a fleeting concern
ahead of the morning commute. Currently, temperatures (and
dewpoints) are similar to last night with reading generally from
the mid 60s northeast to the lower 70s in the southwest, amid
light winds away from any storms.

The models, and their individual ensemble suites, continue to be
in broad agreement with regards to the overall mid and upper
level pattern but differ on the more subtle features that will
impact our weather through the short term portion of the forecast.
They all depict west northwesterly mid-level flow lifting to the
northeast a tad today and then holding rather steady state while
the 5h ridge builds over the Deep South. By 00Z Saturday this
ridge will have pushed into eastern Kentucky with some decent
height rises and likely blunt the impact of passing shortwaves to
the northeast. Even so, a couple more of these impulses will move
east southeast through the region and across the central
Appalachians during the first part of the period. The latest of
these is rather weak as it digs through our area early this
morning. This will be followed by a more defined one arcing
through the middle Ohio Valley tonight - much further away than
these last several passages. Another follows similarly far away
(maybe a tad closer) by Friday evening with at least the upper
pattern suggesting higher 5h heights able to blunt the impacts of
these last two identified perturbations. Again, on account of the
relatively small spread in the models` solutions for the overall
broad pattern aloft, the unadjusted NBM data was used for the bulk
of the grids for this forecast package. However, some
enhancements were made to the PoPs and thunder chances today into
Friday evening primarily through the inclusion of coverage,
timing, and intensity details from the consensus CAMs` solutions -
though generously smoothed and blended temporally with the best
ideas on the timing of these storm clusters.

Sensible weather will feature the late season summertime heat and
humidity continuing to provide instability and fuel for any storm
clusters that manage to make it here through the period. Unlike
the past couple of days, the rising heights aloft and shifting of
mid-level northwest flow pattern will put in doubt the ability for
these systems to dig too deep into our part of Kentucky. Again the
models offer litter ground level consistency for the formation and
movement of these potential clusters. For that reason the Flood
Watch was not extended beyond 12Z this morning, though should
another cluster ignore the height rises it could certainly bring
additional flood concerns into the area through tonight. An
extension or re-issuance will be possible if confidence improves.
Also again, the possible daytime clusters may be organized
enough, or with a a healthy enough cold pool, to yield strong to
wind gusts. Look for temperatures today and Friday to be less
hindered by clouds and passing convection so that upper 80s and
lower 90s will be achievable for most of the area - warmest Friday
afternoon where some mid 90s will be possible. Combined with the
very high dewpoints this afternoon and again on Friday, we will
likely see many spots hit heat indices pushing 100 degrees -
highest in the west and probably even a notch more miserable on
Friday.

The main adjustments to the NBM starting point were to include
the latest CAMs consensus scenarios for PoPs and thunder through
the short term. Considering the high humidity levels limiting the
impacts of radiational cooling at night and lack of dry air
available to mixdown for the afternoons (as well as the still
rather high level of convective uncertainty) - both elements were
mostly left alone for this package.

.LONG TERM...(Friday night through Wednesday)
Issued at 515 AM EDT THU AUG 13 2026

The most current model data continues to suggest the dominance of
the southern upper Ridge into Kentucky over the weekend briefly
limiting convection. However, this dome oh higher heights
retreats southwest in time for the new work week returning the
storm track closer to the state. Right now, SPC has continued a
Marginal severe threat into Saturday for the eastern part of our
area. Meanwhile, WPC continues to highlight excessive rain threats
through Saturday - though the concern is much higher prior to the
weekend.

The previous long term discussion follows:

At the onset of the long term period, eastern Kentucky will find
itself in continued northwest flow aloft, sandwiched between
ridging over the southeastern CONUS and troughing over the
Northeast. At the surface, an area of low pressure will sit over
Atlantic Canada, with a long and poorly defined cold front
extending back through the Mid Atlantic, just north of the
forecast area. This front will sag south through the area on
Friday, bringing a chance for additional convection. As in
previous days, the environment will support intense rainfall rates
with any convection that does pass through; LREF mean PW values
range from 1.8-2 inches on Friday afternoon, well within the 90th
percentile or higher when compared to climatology, and given
already moist soils, flash flood risk could be higher than in
typical summer thunderstorms. WPC has maintained a Day 3 Marginal
(1/4) flash flood risk for our area to account for this.
Additionally, at least moderate instability is likely to build
ahead of the front, which could potentially support strong
convection. Given some model guidance suggests the potential for
additional shortwave impulses within broader northwest flow aloft,
additional MCS type activity cannot be ruled out on Friday
(although uncertainty remains high). That being said, upper level
flow will be weak, with deep layer shear generally favored to
remain under 30 kts across the forecast area, which would not
conventionally support widespread severe weather. Even so, some
machine learning guidance has been comparatively more aggressive
in highlighting eastern Kentucky as a potential location for
additional damaging winds. Given some of the signals in global
models, it is still plausible that MCS activity could increase the
potential for severe wind gusts Friday afternoon/evening,
although confidence in this scenario remains very low. For now,
NBM PoPs were maintained given a lack of baseline model agreement,
but with the caveat that rain chances/timing will require some
refining as uncertainty decreases.

By the weekend, the front will have passed through the forecast
area. Meanwhile, the upper level ridge will continue to build into
our area. This will usher in a period of hotter and drier
weather, with high pressure working to suppress most convection
through the weekend. Unfortunately, the aforementioned cold front
will do little to bring down heat or humidity. Behind the front,
temperatures will actually trend warmer in accordance with
increased upper level ridging (highs likely in the 90s), and
dewpoints will remain in the 70s. Accordingly, apparent
temperatures will be warm, likely in the upper 90s or perhaps even
the low triple digits on Saturday and Sunday afternoons.
Overnight temperatures will only provide limited relief given a
continued moist environment; although radiative conditions will be
ideal, valleys may only end up being a few degrees cooler than
ridges at most, with typical valley fog formation possible
overnight.

Early next week will mark a return to more quasi zonal flow aloft
as an upper level trough begins to dig toward Kentucky and
ridging retreats to the southwest, initiating a return to a
somewhat more active period. Notably, an approaching cold front on
Monday will bring renewed shower and storm chances. In comparison
to the previous cold front, the air mass behind this front will
be marginally drier, with dewpoints expected to fall into the mid
to upper 60s in most locations. High temperatures will also be
around 5 degrees cooler for most locations, marking a return to a
more typical August weather regime.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 313 PM EDT THU AUG 13 2026

Dry weather had returned to the area at the start of the period,
but MVFR ceilings still lingered in some places, mainly around
KSYM, KJKL, KPBX, and points northeastward. Those MVFR ceilings
should be rising and generally scattering out this afternoon.
However, scattered thunderstorms are expected to redevelop as
heating and destabilization occurs. Where and when they occur is
very uncertain. The threat will last into the night, with the
remnant of a thunderstorm complex currently over IL possibly
spurring on the activity as it moves southeast. Fog will probably
affect some locations again overnight and early in the morning,
with favored locations being valleys and in places where rain
falls tonight. The thunderstorms and fog would result in localized
IFR or worse conditions. Outside of that, mainly VFR is forecast
from late today into Friday.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Friday morning for KYZ044-052-104-106-107-
109-110-119-120.

&&

$$

UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...FAGAN/GREIF
AVIATION...HAL