344
FXUS63 KLMK 152314
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
714 PM EDT Tue Sep 15 2026

...Updated Aviation Discussion...

.KEY MESSAGES...

* Heat Advisory is in effect and has been extended through the day
  Thursday.

* Unseasonably hot temperatures will continue until the end of the
  week. Daily highs in the in the mid/upper 90s with heat index
  values above 100 to 105 degrees. Overnight lows only bottom out in
  the low/mid 70s.

* Mainly dry through the end of the week with low end (10% or less)
  chance of isolates showers or storms.


* Low (10-30%) rain chances return late in the week into the
  weekend, with a significant cooldown unlikely through Sunday.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 247 PM EDT Tue Sep 15 2026

Late season heat will be the main impact through the end of the
week as we will remain under a very strong 600 dm upper ridge. Heat
Advisory remains in effect and was extended through the day Thursday
for most of central and western KY and all of southern IN. Locations
inside the advisory will experience daily highs in the mid to upper
90s with heat index values ranging from 100-105 degrees. At night,
temperatures will remain unseasonably warm with overnight lows in
the low to mid 70s. Outside of the advisory, across the Bluegrass
and along and east of the I-75 corridor, it will still be very warm
but highs will be in the low 90s with heat index values in the upper
90s. Each day the wet bulb globe temperature (WBGT) will be around
or above 85 and up to 88 degrees. The Heat Advisory may need to be
extended into Friday but with a few counties trimmed to the north
and east as the overall ridge starts to flatten out, retrogrades
to the west and a cold front drops southward towards the Ohio River.

Cold front currently over the Upper Midwest will slowly work east-
southeast into northern and central IN later tonight. With 850
temperatures around 20-22 degrees and the influence of the strong
upper ridge and sfc high, and convection that gets fired should
diminish as it moves southward towards the Ohio River. There is just
a small chance (less than 10 percent) that any precipitation works
into the region overnight. By tomorrow morning, the cold front
should stall just to our north and then begin to lift northward as a
warm front. Some of the hi-res models want to show isolated activity
across the area tomorrow afternoon but current thinking is we stay
mostly dry and confidence in this scenario remains low.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 247 PM EDT Tue Sep 15 2026

By the end of the week the warm front will sag south as a cold front
and stall near the Ohio River once again, This will bring an
increased chance of showers and storms (10-30 percent) mainly across
southern IN and east of I-65. As of now activity looks relatively
scattered to isolated with low QPF. This will bring slightly cooler
temperatures with highs in the low/mid 90s and upper 80s across the
Bluegrass. Heat advisory may need to remain in place for locations
to the west and south for the end of the week.

The weekend looks to be split with temperatures still remaining
unseasonably warm on Saturday as the aforementioned front lifts back
north as a warm front allowing for high to get back to around the
mid 90s and mostly dry but a weak shortwave trough working over the
top of the retrograding upper ridge will push a stronger cold front
through by the end of the weekend and into early next week. We will
see an increased chance of showers and storms with this system and
cooler temperatures into the 80s by the start of next week.

&&

.AVIATION /00Z TAFS THROUGH 06Z THURSDAY/...
Issued at 714 PM EDT Tue Sep 15 2026

VFR conditions are expected to continue through the forecast period.
Mostly clear skycover overnight with light winds from the south. For
tomorrow, should see some diurnal cu develop again, but VFR will
continue with winds from the SW.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...Heat Advisory until 8 PM EDT /7 PM CDT/ Thursday for
     KYZ023>034-038-045-046-053-054-061>065-070>077-081.
IN...Heat Advisory until 8 PM EDT /7 PM CDT/ Thursday for
     INZ076>079-083-084-089>092.

&&

$$

SHORT TERM...BTN
LONG TERM...BTN
AVIATION...CJP