244
FXUS63 KJKL 190551
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
151 AM EDT Thu Jun 19 2025

.KEY MESSAGES...

- Showers and thunderstorms are expected at times through
  Thursday, with the potential for high water or flash flooding.

- Some storms this evening into tonight and on Thursday could
  produce strong to damaging wind gusts.

- Seasonably warm high temperatures are forecast through most of
  the week, with heat then building during the weekend and
  especially the first half of next week.

&&

.UPDATE...
Issued at 1058 PM EDT WED JUN 18 2025

The line of showers and storms that we have been watching is now
starting to enter the western portions of the CWA. These showers
so far have been bringing us heavy rain and gusty winds up to
40mph. While the severe threat has lowered from when the storms
were further west, the possibility for a storm to reach severe
criteria remains. The main threat with any severe storms is still
damaging wind gusts. This line will move across the area over the
next few hours, generally between now and 6z. Tweaked the PoP
grids some to better refine the timing of the rainfall, in
addition to blending in obs.

UPDATE Issued at 827 PM EDT WED JUN 18 2025

The main feature of interest this evening is the line of storms to
our west across the middle of the state. That line will keep pushing
east over the next several hours, carrying the threat of hail and
damaging winds with it. A Severe Thunderstorm Watch is in effect
until 1 AM EDT for all but our far eastern counties. The severe
threat is currently expected to diminish around the time it gets
into that area, but this will continue to be evaluated going through
the night. Updated PoP grids to try and capture the timing of this
line of storms, but otherwise, the going forecast is on track.

&&

.SHORT TERM...(This evening through Thursday night)
Issued at 355 PM EDT WED JUN 18 2025

Late this afternoon, an upper level ridge was centered east of the
southeast US Coast while an upper trough extended from the
Northern Great Lakes to mid MS Valley to the Arklatex vicinity.
One or more weaker shortwaves were moving across the OH Valley and
Great Lakes regions in advance of the trough axis. Meanwhile
upper level ridging was centered off the Baja of Mexico coast and
extended into the Southwest Conus to parts of the Southern Plains
as well as north into parts of the Northern Rockies. Further
northwest, an upper level low was nearing the coast of BC with an
associated south that was nearing the Pacific Northwest. At the
surface, a frontal zone extended from low pressure in Quebec to a
sfc low in IL and then south and southwest to the Southern
Plains. Locally over eastern KY heating of a moist airmass into
the 80s dewpoints in the upper 60s near the VA border and low to
mid 70s elsewhere has resulted in MLCAPE analyzed at 1500 to 2500
J/kg with MUCAPE near 3000 J/kg. Shear is rather low end
generally 20 to 25KT in the east with a min in shear near the I-75
corridor while shear increases further west nearer to the
approaching boundary and trough. Low level lapse rates are
currently analyzed from near 6.5C/km or 7.5C/km with mid level
lapse rates of 5.5 C/km to 6.5C/km while DCAPE is roughly in the
600 to 800 J/kg range. A few pulse type storms have developed and
move across the area this afternoon and a strong to locally severe
gust could occur with any storms that might manage to develop
though given the minimal shear a lull in the activity is
anticipated for eastern KY for the next several hours.

The upper level trough axis should approach eastern KY this
evening and tonight, crossing the area later Thursday into
Thursday evening and then east of the area by late Thursday night.
A cold front should precede this across the area from midday
Thursday into early THursday evening, trialing from low pressure
tracking across the Great Lakes to the St Lawrence Valley and
Northeast through Thursday night. Meanwhile, a preceding shortwave
trough in advance of the front has led to ongoing linear
convection from IN and IL south into western KY. This should
continue east per CAMS at least maintaining a cold pool with the
activity likely to near the KCVG and northern KY area before
sunset and perhaps reach the I-64 corridor counties near sunset
while the southern portions of the linear convection should near
the Lake Cumberland region a couple of hours later in the evening,
progressing further east and southeast into the overnight hours.
RAP has mid level lapse rates becoming slightly better over the
next 6 hours at near 6C/km with some CAPE remaining tough some CIN
will also begin to develop over the area by late evening.
Effective wind shear should increase to 20 to 30KT at that time.
Although there will be lesser instability over far eastern KY as
compared to locations further west the threat for strong to
damaging winds will linger, especially western portions of the
area and possibly to the WV and VA borders. Shear will be slightly
better from northwest of the I-64 corridor to west of Lake
Cumberland and in those areas a brief spin up tornado cannot be
completely ruled out with the liner convection/QLCS. The recent
SPC Outlook has expanded the Slight Risk further into east KY
while brushing the 3 northwestern counties with an enhanced risk.
Torrential downpours remain a threat and areas that receive
multiple rounds of stronger thunderstorms could experience high
water or localized flash flooding.

Following this prefrontal convection, renewed convection is
anticipated ahead of the front on Thursday with some daytime
heating. Some of this convection could also become strong and
produce strong to locally damaging winds gusts. With the moist
airmass remaining ahead of the front, torrential downpours will
remain a threat and areas that receive multiple rounds of
stronger thunderstorms could experience high water or localized
flash flooding. Chances for showers and storms will diminish from
northwest to southeast by late Thursday afternoon to early evening
near and north of I-64 and near or just after sunset further
southeast. Clearing skies with high pressure building in and
slackening winds following recent rainfall should set the stage
for fog formation perhaps not only in valleys but perhaps more
widespread. Dense fog is also a possibility, but confidence was
not high enough to mention dense just yet.

.LONG TERM...(Friday through Wednesday)
Issued at 330 PM EDT WED JUN 18 2025

The period is expected to begin with an upper level trough axis
extending from Quebec to the mid Atlantic coast to the coast of
the Carolinas an upper level ridging extending form the Gulf
across the Southern Plains to northern Mexico while an upper
level low should be nearing the Pacific Northwest with an
associated trough moving into the western Conus. At that point a
sfc ridge of high pressure is expected to be centered over
northeast TN/Southern Appalachians while the boundary that will
have crossed eastern KY during the short term period should have
pushed into the Carolinas to northern GA. Meanwhile a frontal zone
should generally extend from the St Lawrence Valley to the
northern Great Lakes to northern Plains to MT at that point.

The upper level ridge is expected to build north and northeast to
end the week and into the weekend into the Lower to Middle MS
Valley to Southeast/Appalachians to OH Valley, becoming centered
over the Commonwealth with 594+ dm heights by late Sat over the
state. Heights are expected to rise even further on Sunday with
596+ dm heights over much of the OH Valley and arts of the Central
Appalachians by late Sunday. Meanwhile as the ridge builds in the
eastern Conus, a trough should evolve over the western Conus to
northern Plains regions. The upper level ridge is progged to begin
to gradually weaken by Monday to Wednesday though ECMWF guidance
generally remains stronger with the upper ridge centered over the
Southern Appalachians at midweek while GFS guidance is weaker and
more enlongated with the ridge from the OH Valley to the mid
Atlantic states/portions of the northeast Coast. Meanwhile the one
or more shortwave troughs should move from the northern
Rockies/Northern Plains to the northern Great Lakes and toward the
St Lawrence Valley. Lower height solutions would have weaker
capping and more chances for diurnally driven convection while the
recent ECMWF operational runs are drier solution. The consensus
of guidance is for increasing heat from the weekend into the first
half of next week with precipitation free weather through Monday.
Heat indices should peak near or in excess of 100 by Monday to
Wednesday. NBM probs as well as ENS and GEFS based probabilistic
guidance have increasing chances for convection into midweek.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 151 AM EDT THU JUN 19 2025

Scattered showers and storms will continue to move across the area
through the overnight hours, bringing gusty winds and reduced
visibilities to any TAF sites they might affect. Late tonight into
tomorrow morning, MVFR level ceilings are anticipated to move in
ahead of an approaching cold front, along with more chances for
showers and storms, but are expected to lift to VFR levels in the
afternoon. However the chances for showers and storms remain,
only really beginning to decrease tomorrow evening. Outside of
any erratic gusts within thunderstorms, winds are expected to
remain out of the southwest, between 5 and 10 kts tonight, peaking
between 7 and 12 kts tomorrow afternoon. Winds start to decrease
in the evening/nighttime hours tomorrow, as cloud cover and rain
chances decrease as well.


&&

.JKL WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...HAS
SHORT TERM...JP
LONG TERM...JP
AVIATION...HAS