732
FXUS63 KLMK 101803
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
203 PM EDT Thu Sep 10 2026

...Updated Aviation Discussion...

.KEY MESSAGES...

* A cold front arrives today with 80-90% chance of showers and a few
  storms possible. Fairly widespread rainfall between .5" - 1" is
  expected with locally higher amounts over 1.5" possible,
  especially along and north of I-64. A few localized areas could
  see 3"+ which could lead to a some flooding concerns.

* This weekend is expected to remain active with off and on isolated
  to scattered showers and storms.

* Overall drier and hotter conditions arrive early next week.

&&

.UPDATE...
Issued at 1034 AM EDT Thu Sep 10 2026

Morning satellite imagery shows mostly cloudy skies across southern
IN and much of central KY this morning.  Some partial clearing was
noted across southwest and far southern KY.  Temperatures were
mainly in the low-mid 70s under the clouds, but where filtered
sunshine was noted, temperatures were in the upper 70s to near 80
along the KY/TN border.

Initial batch of morning convection continues to push on off to the
east and is now located from Flemingsburg southwest to near
Campbellsville.  Convection seems to be aided by the nocturnal low-
level jet axis which will continue to move eastward through the
morning hours.  Surface cold frontal boundary is still north of the
CWA in central IN and will continue to track southward this morning.

For the remainder of the morning hours, we`ll see a brief break in
the rainfall from SE IN down into portions of north-central KY.
However, another band of showers across southwest/southern IN will
gradually work eastward ahead of the approaching frontal boundary
from the north.  Abundant cloud cover and ongoing precipitation will
likely result in keeping stability across the region down this
afternoon, with the exception of southern KY where filtered sunshine
may allow MLCAPE values to get into the 1200-1700 J/Kg range this
afternoon.  However, the low-level jet axis will continue to move
eastward and should be well east of the area this afternoon.  We do
expect storms to redevelop during the afternoon hours.  Some strong
storms are possible with wet microbursts being the primary threat
posing a small damaging wind risk across the area.  High moisture
content will keep PWAT values up and some swaths of heavy rainfall
are possible, yielding widely scattered instances of hydro issues
across the region.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 240 AM EDT Thu Sep 10 2026

Scattered showers and a few storms will continue early this morning
as subtle low level jetting (~25 knots) continues to respond beneath
favorable right entrance region upper jet structure. As we move
toward dawn and into the late morning hours, it appears there could
be a bit of an uptick as shortwave energy ejects out of the Plains
into the mid Mississippi River Valley. This will also occur as the
weak surface frontal boundary will start to slide southward toward
the Ohio River. The end result should be clusters of showers and
storms capable of locally heavy rain and gusty winds. PWATs look to
surge over 2" through the column, and with 500-1000 J/KG of ML CAPE
expected we could see a few water loaded downbursts in the most
intense precip cores. Later on this afternoon, ML CAPE values look
to rise into the 1500-2000 J/KG range along and south of the Ohio
River (ahead of the surface front). By this time, the overall deep
layer shear will be weakened, especially in the low levels with the
loss of the LLJ. Still, could get a few localized downbursts, along
with a continued heavy rain threat thanks to high PWATs, relatively
slow movement, and efficient rainfall processes. Still seeing some
locally high values over 2-3"+ showing up in the HREF PMM data,
which adds confidence to what the meteorological data showing the
locally heavy rain potential is plausible. Don`t have enough
confidence in coverage and/or placement to focus Flood headline at
this time, but will continue to message the potential for some low-
end localized flooding concerns.

The surface front will be slow to push south, so will linger some
shower chances into late tonight across KY, with southern IN likely
staying more dry. Overall intensity should be somewhat diminished by
this time with the loss of the best instability and the front
starting to wash out.

The good news is that the increased shower and storm activity
combined with the weak surface front dropping south will provide
some relief in temperatures today, at least for southern IN and
north central KY. Southern KY will still hold onto upper 80s and low
90s south of the surface boundary.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 240 AM EDT Thu Sep 10 2026

Friday - Saturday...

The weak surface boundary will be stalled somewhere near the KY/TN
border on Friday, with a weak and meandering shortwave over the mid
Mississippi River Valley. A high PWAT airmass will pool over our
area ahead of this weak upper trough axis with showers and storm
chances continuing mainly each afternoon and evening. The overall
deep layer shear profile will be weak, so any slow moving storm may
be capable of localized heavy rain given the high moisture content.
1000-1500 J/KG of CAPE in a tall/skinny profile combined with 2 -
2.25" PWATS, high freezing levels above 15K feet, and slow movement
will be quite efficient with rain rates. Something to watch going
into the first part of the weekend.

Temperatures each day will be mostly in the low and mid 80s,
although the southern and western CWA could sneak into the upper
80s. Will keep pops pretty high through this period given the amount
of deeper moisture and a triggering mechanism.

Sunday - Tuesday...

Looks to be a drier and hotter stretch of weather for the end of the
weekend going into early next week. The southern CONUS ridge will
build back over the area, pushing the stronger westerlies much
farther north. This will put us in a mostly subsident and dry
pattern as forecast soundings do show an impressive H7 inversion.
Hotter temperatures will also accompany this upper pattern change
with afternoon highs back in the upper 80s and low 90s by Tuesday.

Wednesday...

There seems to be fairly decent model agreement (for Day 7 anyway),
that the upper ridge breaks down a bit by mid week, and allows a
cold front to approach our region. This would bring a return of
showers and thunderstorms to the area, if correct. In addition,
temperatures would probably step back toward normal temps back in
the 80s.

&&

.AVIATION /18Z TAFS THROUGH 00Z SATURDAY/...
Issued at 203 PM EDT Thu Sep 10 2026

Showers continue to move through southern Indiana, with scattered
thunderstorms starting to pop up across south-central Kentucky.
These storms should be individually short-lived, but will continue
to spawn across the southern portion of Kentucky. Winds shift from
northwesterly to a weak variable/northeasterly overnight, with
any gusts associated with a passing shower. Patchy fog sets in in
the morning alongside low CIGs, especially in places that received
moderate rainfall in the past day, with HNB/RGA/LEX in IFR
visibilities. CIGs across the whole area should remain VFR outside
of passing storms until this evening, when the whole area settles
into likely MVFR clouds before letting up tomorrow mid-morning.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.

&&

$$

UPDATE.......MJ
SHORT TERM...BJS
LONG TERM....BJS
AVIATION.....JPH