057
FXUS63 KLMK 051937
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
337 PM EDT Sat Sep 5 2026

.KEY MESSAGES...

* Heat Advisory continues for counties west of Scott County, IN
  and Clinton County, KY.

* Scattered storms with a low-end gusty wind threat ends this
  evening, especially across the western CWA.

* Cooler and much drier air moves in Sunday-Monday with another
  quick heatwave moving in Tuesday-Wednesday.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 337 PM EDT Sat Sep 5 2026

===== This Evening - Sunday Night =====

Anticipating additional scattered convection this afternoon and
evening. Already seeing scattered cumulus forming along the stalled
out boundary over our west/southwestern counties towards Bowling
Green. These areas will likely see the first of any storms. As the
evening progresses, these storms will grow in coverage, more so
across the west. There is decent instability with mixed layer CAPE
upwards of 2,500 to 3,000 J/kg according to the latest mesoanalysis.
Downdraft cape is near or just above 1,000 J/kg as well, meaning any
storm that develops carries mainly a risk of strong winds from
downburst and possibly small hail considering the amount of
instability. Considering how dry the CWA has been, we`re not
necessarily concerned with flooding with these storms, however
should one or two train over the same areas, low-end flash flooding
is a possibility. Latest HREF LPMM data suggests isolated areas 2-
3". However, the whole area has a ~90% of remaining under 0.5" this
afternoon according to the latest HREF guidance as well.

That being said, this afternoon has been hot with heat indices
reaching the mid 100s in the central and western CWA. A heat
advisory continues until 8 PM EDT for this excessive heat. Good news
is that after any storms this evening, a backdoor cold front will
sweep through thanks to a trough over the eastern seaboard. This
will help drop dew points and temperatures overnight and into
tomorrow. Lows tonight will be in the upper 60s and low 70s, with
the coolest areas in the NE closest to the approaching front.

By Sunday morning, there will be a notable difference in how muggy
the air will feel. With a continued NE flow, dew points will
continue to drop throughout the day, making highs in the low to mid
and isolated upper 80s that much more comfortable. Skies will be
mostly clear and PWATs will decrease to the climatological 20th
percentile or lower. Meaning this will be a very dry air mass moving
in Sunday afternoon and evening. Lows Sunday are cooler in the low
to mid 60s.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 337 PM EDT Sat Sep 5 2026

===== Monday - Saturday =====

Beginning Monday morning, we remain on the cool side of a surface
high with a continued NE flow keeping highs in the mid to upper 80s.
As dry as the air mass will be, PoPs will remain near zero for the
whole CWA with near normal highs. Overall synoptic pattern changes
slightly as an Omega pattern begins to break down some. The ridge in
place over the plains will begin to move south with more of a zonal
flow setting up over our area through the week.

At the surface, high pressure at the surface will shift east, and a
southeasterly to eventually southwesterly flow will return. Highs
will be boosted as a result into the 90s once again by Tuesday-
Wednesday. With the weakened ridge over the plains, a trough will
move through our area by later Wednesday and Thursday morning. A
boundary will set up somewhere over the Ohio Valley acting as an
axis for moisture to travel on. Rain chances mixed with storms
returns by then with slightly cooler highs in the mid to upper 80s.
Depending on how far south the boundary pushes later in the week
will determine if highs remain in the 80s by Friday and Saturday or
not. For now, expect drier conditions to return by next weekend.

&&

.AVIATION /18Z TAFS THROUGH 00Z MONDAY/...
Issued at 241 PM EDT Sat Sep 5 2026

Variable light winds and mostly clear skies will transition to a
predominant NW wind and scattered storms later this afternoon and
evening. Moving in from the north, any storms that develop will have
the potential to bring temporary MVFR-IFR ceilings and visibilities
with wind gusts up to 35 kts. Those that dodge storms will remain
VFR with a predominant light NW flow. Once storms fade, light to
calm winds with SCT-BKN cloud cover will move in overnight. High-end
MVFR to low end VFR ceilings move in later in the morning with VFR
conditions returning Sunday afternoon.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...Heat Advisory until 8 PM EDT /7 PM CDT/ this evening for
     KYZ023>031-038-045-046-053-054-061>065-070>078-081-082.
IN...Heat Advisory until 8 PM EDT /7 PM CDT/ this evening for
     INZ076>078-083-084-089>092.

&&

$$

SHORT TERM...BKF
LONG TERM...BKF
AVIATION...BKF