316
FXUS63 KJKL 152149
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
549 PM EDT Sat Aug 15 2026

.KEY MESSAGES...

- The potential for showers and thunderstorms will persist through
  the weekend.

- 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,
  or train, leading to flash flooding.

- Heat indices will flirt with Heat Advisory levels (105F +) again
  on Sunday afternoon.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 520 PM EDT SAT AUG 15 2026

Early this evening, multiple outflows and scattered or greater
coverage of convection has occurred across the northern and
eastern half to two thirds of the area this afternoon.
Temperatures in outflowed areas are in the upper 70s to mid 80s.
Further southwest, temperatures are in the upper 80s to around 90.
A quasi stationary boundary remains generally just south of the
OH River in northeast KY and then near or just east of the WV and
KY border and into SW VA. Some convection is occurring nearer to
this boundary and near an effective differential heating boundary
from near Montgomery County to Clay and Leslie County. In the
southwest, mid level heights are higher and that area is nearer to
the center of the ridge. Cumulus has been more suppressed there.
Mid level lapse rates are analyzed in the 5.5 to 6C/km range,
while low level lapse rates in the western half o the area are in
the 6.5 to 7.5 C/km range. MLCAPE is analyzed in the 2000 to
nearly 3000 J/kg range while effective shear is minimal 20KT or
less for most areas and nearer to 25KT near and north of the I-64
corridor. PW has increased from midday to the 1.85 to 2.1 inch
range.

This evening into tonight, the MCV/shortwave is expected to track
north and northeast of eastern KY while the upper ridge remains
centered in the Arklatex region and extend across much of the TN
Valley and into the Northeast. On Sunday, the ridge is progged to
become centered over the Southern Plains/TX and remain there
through the end of the period. Further north, the shortwave
currently extending from Manitoba into the Dakotas will move east
to Ontario and the Great Lakes and then continue east to Quebec
and the eastern Great Lakes and the Northeast Conus to mid
Atlantic states to end the period. Meanwhile, at the surface, the
quasi stationary boundary currently from northeastern KY then
southeast near the WV and KY border into SW VA should lift
northeast as a warm front into the Great Lakes to mid Atlantic
into the day on Sunday while the cold front associated with the
shortwave moving across Canada reaches the Central Great Lakes to
mid MS Valley to OK and TX panhandle. This front will move into
the Northeast to mid OH Valley and sag into or toward the
Commonwealth to end the period.

Ongoing convection may continue in the western part of the area
near the effective differential heating boundary and near
outflows. With the high PW values, any training cells could result
in additional high water or flash flood concerns. The passing
MCV/shortwave may lead to additional convection through late this
evening or into part of the overnight, mainly for the north and
east. If there is any training from that activity, the chances for
high water or flash flooding would continue. The quasi stationary
boundary will be over near the northern and eastern sections of
the area as well and in those areas, isolated to scattered pops
were maintained for late this evening and most of tonight. Sunday,
the entire region should get into the warm sector, with isolated
storms not out of the question in the afternoon. By late
afternoon/early evening, chances for convection should increase
form the north or northwest as the cold front approaches. One or
more areas of convection may cross the area on Sunday night as
progged by the CAMS. If these move over northern and eastern
sections with pockets of heavy rain that fell today or fall
through this evening, additional high water or flash flooding is
possible. At least moderate instability is also anticipated for
Sunday convection and damaging winds could again be a threat.

Outside of convection, if and where clearing occurs, especially
for valleys areas, fog should develop both tonight and on Sunday
night. Some of that may become dense. Heat indices could top 100
and near 105 again mainly near the Lake Cumberland region and some
deeper valley locations.

.LONG TERM...(Monday through Saturday)
Issued at 510 PM EDT SAT AUG 15 2026

The long term period will open with upper level ridging over the
southern CONUS and troughing over the Northern Plains into the
Upper Great Lakes region, maintaining northwest flow aloft.
Meanwhile, at the surface, an area of low pressure will be located
in the vicinity of western Kentucky, with a frontal boundary
sitting just west of the area. This boundary will push through the
forecast area as a cold front on Monday, bringing renewed shower
and storm chances. As in previous days, the environment will be
very moist, with PW values generally in the range of 1.7-1.9 in.
Thermodynamic profiles also look to be supportive of torrential
downpours, with a deep warm cloud layer and LREF mean MUCAPE in
the range of 2000-2500 J/kg across the forecast area. Given these
indicators and the expectation that soils will be fairly
saturated, isolated flash flooding will be possible. In fact, WPC
has placed the entire forecast area in a Day 3 Marginal (Level
1/4) Risk for Excessive Rainfall to cover this flash flood threat.
Rain chances will peak Monday afternoon into evening; then,
following the frontal passage, drier air will advect in from the
north. By Tuesday, dewpoints will be only in the mid to upper 60s,
with perhaps a few areas in the 70s in the southwestern corner of
the forecast area. Highs will also be marginally cooler,
generally in the mid to upper 80s, and rain chances are looking to
be low. Of note, a few recent model runs do depict subtle
shortwave energy traversing the area, which could inspire a few
showers or storms, although this scenario still appears unlikely
at this time.

The next robust rain chances will arrive Wednesday evening into
the overnight hours. Aloft, troughing will continue to dig into
the Great Lakes region, and the ridge to the south will continue
to flatten. Meanwhile, an additional cold front will push
southeast, with rain chances ticking up again late Wednesday.
Moisture will return quite quickly as winds become southwesterly
ahead of the front, and PW values look to leap again too (with
LREF mean PW in the 1.6-1.7 in range for much of the area,
representing at least the 75th percentile compared to
climatology). As in previous days, this environment could support
at least an isolated flash flooding risk; WPC has again placed the
majority of the forecast area in a Day 5 Marginal (Level 1/4)
Risk for Excessive Rainfall (covering Wednesday morning through
Thursday morning).

Behind the front, temperatures will be noticeably cooler. With
eastern Kentucky sitting near the base of the upper level trough,
flow aloft will either be zonal or northwesterly, with models
still disagreeing about the exact orientation of the trough at
this stage in the forecast. Regardless, this pattern will open
eastern Kentucky up to additional shortwave impulses. Although
exact timing is difficult to resolve at this timescale, broad rain
chances have been maintained each day through the end of the
period for now.

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 300 PM EDT SAT AUG 15 2026

Mainly VFR was observed across eastern KY at issuance time, but
cumulus had begun to develop across the north and east with some
showers and thunderstorms across the region. KSME and KLOZ will
be located further from the quasi stationary sfc boundary and
closer to the upper ridge and will have the least chance for
convection during the first 6 hours of the period as we move
through peak afternoon heating. Meanwhile, isolated to scattered
showers and thunderstorms are anticipated elsewhere with brief
reductions to MVFR or even lower along with wind gusts up to 30KT.
Some convection could affect areas from near KIOB to KJKL and
points north and east including KSYM and KSJS during the second 6
hours of the period as a disturbance passes. However, following
afternoon convection there is uncertainty the extent of any of
this possible activity. Thus, PROB30 groups were restricted to the
timeframe through 00Z and left out after. Some fog or low stratus
could also become a concern, but confidence outside of the deeper
valleys in the north and east was too low low to include at any of
the TAF sites at this point. Winds will generally be 10KT or
less, except locally stronger and erratic near thunderstorms.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM EDT this evening for KYZ083.

&&

$$

SHORT TERM...JP
LONG TERM...FAGAN
AVIATION...JP