835
FXUS63 KLMK 250700
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
300 AM EDT Sat Jul 25 2026

.KEY MESSAGES...

* Some spotty shower and storm chances return heading into the
  weekend, and heat and humidity return late weekend into early next
  week. Max afternoon heat indices could be in the triple digits for
  some by early next week.

* A round or two of stronger thunderstorms is possible Monday and/or
  Tuesday, however confidence remains low on the finer details.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 300 AM EDT Sat Jul 25 2026

Things are mostly quiet across the CWA at this hour, although we are
seeing some light returns on radar, mainly across the southern and
western CWA. We`re getting a slight uptick in the low level jet as
the entrance region of an upper level impulse noses into the area.
This is providing just enough isentropic lift (evident on 300k
analysis) to squeeze out some sprinkles and very light showers. T/Td
spreads still remain pretty high on a lot of obs, so not expecting
the better chances for measurable showers until later this morning
into the day. By then, low level moisture and an overall higher PWAT
airmass should be in place. We don`t have a lot in the way of
instability (MU CAPE < 500 J/KG) this morning, so expecting only
showers. However, a few thunderstorms might be possible by this
afternoon, especially west of I-65 where some modest instability
values could develop. Overall, expecting only isolated to widely
scattered coverage with many spots continuing to stay dry today.

Expect temps to be a couple/few degrees warmer than yesterday, but
still a bit below normal for this time of year. Looking for highs
mostly in the lower mid 80s. Low level moisture continues to push
into the area tonight, and this combined with plenty of cloud cover
should yield overnight lows quite a bit milder than previous nights.
Upper 60s and low 70s will be common. A few showers or a storm could
persist through the overnight, especially across the southern CWA.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 300 AM EDT Sat Jul 25 2026

Sunday - Tuesday Night...

Heat and humidity take a notable jump on Sunday as the strong
western and central CONUS ridge becomes more established to our
west. Expecting afternoon highs to peak in the upper 80s to around
90 across the area, along with a notable jump in surface dewpoints
to the low and mid 70s for most. The resulting max heat indices are
expected to reach into the 95 to 100 degree range for some locations
mainly along and west of I-65. Could take some folks off guard given
the recent pleasant stretch of T/Tds we just had.

NW flow will continue over our region on the eastern periphery of
the upper ridge, however Sunday looks to be mostly void of any
notable triggering features. The lack of a trigger combined with
some capping between H85-H7 on soundings suggest we`ll stay mostly
dry through the day. This notion is backed up by current model data,
and it is a good thing as we will be strongly unstable (3000-4000
J/KG of ML/SB CAPE).

The bigger storm concern focuses on later Sunday night through
Monday night, and possibly again on Tuesday. Forecast data has been
fairly consistent in suggesting that a convective complex or two
could develop upstream and move through the NW flow pattern sometime
in the Monday/Tuesday timeframe, although it has been inconsistent
run to run with timing/placement, etc. It does appear that a series
of shortwaves embedded within the NW flow aloft will trigger
complexes up toward the western Great Lakes, and then ride SE on the
NW flow pattern. Still don`t have a lot of confidence on whether
these complexes will impact our CWA or stay to the NE. Past
experience has shown that a combination of 700-300mb mean wind
combined with instability gradients can be a good way to determine
cold pool driven MCS paths. Looks like we could easily have 4000+
J/KG of SB CAPE available across the entire Ohio River Valley region
by Monday, however the sharp gradient evident on Sunday will be more
broad and not well defined by Monday. As a result, expect the 700-
300 mb mean wind to be more of the driver of any cold pool driven
forward propagating MCS in this particular scenario. This probably
makes the more likely scenario that the bulk of MCS activity stays
to our north and east, and only brings western portions of any
convective complexes into play for us. That being said, a widespread
damaging wind event is still a scenario that could occur and it
still looks most likely across the NE half of the CWA sometime
Monday-Tuesday.

Will have to keep our guard up and monitor hi-res CAM guidance over
the next 48 hours as a severe threat will come into play if any of
the convective complexes do end up impacting our area. Strong
instability combined with plenty of deep layer shear (mainly driven
by mid and upper level jet dynamics) would be capable of producing a
wind damage threat, perhaps widespread wind damage if a good cold
pool does get going upstream and forward propagates into our area.
Like the addition of our area to the SPC Outlooks as it is kinda of
an all or nothing type of scenario to message. Just keep in mind
that it is conditional.

If we do stay mostly dry into the early part of the week then the
big story will end up being the heat and humidity. Talking about
this 2nd since it is dependent on a convectively reinforced cold
pool not diving in here and wrecking the temperature forecast. The
current forecast calls for highs in the lower 90s both Monday and
Tuesday. These values combined with dew points surging into the low
and mid 70s could yield max heat indices up around 105 in some spots
each afternoon. This would mainly be for area along and west of I-
65, and may need a Heat Advisory to cover this assuming we are able
to stay more dry than not.

Wednesday - Friday...

NW flow aloft continues to persist over our area through mid to late
week between the central/western CONUS ridge and the New England
troughing. There is decent model agreement that we stay mostly dry
during this time as the NW flow aloft doesn`t look to harbor any
embedded shortwaves. Still a bit early to be too confident, but for
now it looks like the heat and humidity also back off a bit during
this time. Highs look more around normal and mostly in the upper 80s
during this stretch.

&&

.AVIATION /06Z TAFS THROUGH 12Z SUNDAY/...
Issued at 127 AM EDT Sat Jul 25 2026

A few light showers have been noted near the BWG/RGA TAF sites early
this morning, however will mainly focus on any additional shower
chances at BWG through around or just after sunrise. Cloud ceilings
should steadily lower to the 4-6 K feet range through the day, with
perhaps some sprinkles at times. Currently calm winds should find a
light SW or S component through the day. Perhaps some MVFR ceilings
move in toward the end of this TAF cycle, but confidence isn`t high
enough to mention in TAF at this time.

&&

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

&&

$$

SHORT TERM...BJS
LONG TERM...BJS
AVIATION...BJS