033
FXUS63 KLMK 131928
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
328 PM EDT Sun Sep 13 2026

.KEY MESSAGES...

* This evening and tonight, a weak cold front could bring an
  isolated shower or storm, mainly across southern Indiana and
  northern Kentucky.

* Tuesday, overall drier and hotter conditions arrive as an upper
  ridge builds. A Heat Advisory has been issued for Tuesday
  afternoon.

* Heat remains through at least Thursday this week, before chances
  for showers and storms enter the forecast at the end of the week.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 328 PM EDT Sun Sep 13 2026

The cold front will move through the region this evening. Very
isolated showers will be possible over southern Indiana. Otherwise,
tonight we will see temperatures cool down into the upper 50s and
low 60s.

On Monday and into Monday night, surface high pressure centered over
the Ohio Valley will move east and southerly flow will return to the
region. High temperatures will be in the 80s, and most likely the
coolest day of this week.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 328 PM EDT Sun Sep 13 2026

On Tuesday, ridging will be centered over the Ohio Valley. Surface
high pressure will keep pushing east, which will promote
southwesterly flow into the region. A low pressure system will move
through southern Canada, which will tighten the pressure gradient
over the region. Breezy winds, increased moisture, and hot
temperatures are expected for Tuesday. Peak heat indices will be 97-
100F (in the Bluegrass) and 100-106F elsewhere. A heat advisory has
been issued for the western half of the region for Tuesday.

Similar conditions will last through at least mid week. High
temperatures will remain in the mid 90s through Thursday. A heat
advisory will likely need to be continued through mid week. Given
the time of year, these temperatures and heat indices are unusual
(about 10-12 degrees above normal). HeatRisk is expected to be Major
(level 3/4) Tuesday through at least Thursday. NBM (and associated
guidance) is likely not handling temperatures as well, given decent
southwesterly flow and the beginnings of the transition season.
Therefore, have bumped temperatures bit a bit, specifically
overnight. Looking at records, we may approach both high
temperatures and warm mins this week.

Moving into Friday and the weekend, ridging remains over the
southern CONUS, though multiple shortwaves will attempt to move
across the region. This would bring isolated to scattered showers
and storms and slightly cooler temperatures.

&&

.AVIATION /18Z TAFS THROUGH 00Z TUESDAY/...
Issued at 107 PM EDT Sun Sep 13 2026

Light winds begin in a westerly direction at around 5 kts this
afternoon before slowly turning toward the northerly direction and
picking up to around 10 kts. An isolated few gusts of around 18 kts
are possible later this evening. The wind then shifts to a
northeasterly direction in the early morning hours. Very small
chances of showers are in the forecast, but confidence is far too
low to include in even a PROB30 group. Fog remains possible in the
early morning, but confidence is low. CIGs will remain VFR while a
slightly lower scattered cloud deck approaches overnight.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...Heat Advisory from noon EDT /11 AM CDT/ to 8 PM EDT /7 PM CDT/
     Tuesday for KYZ023>030-038-045-053-061>064-070>076.
IN...Heat Advisory from noon EDT /11 AM CDT/ to 8 PM EDT /7 PM CDT/
     Tuesday for INZ076>078-083-084-089>092.

&&

$$

SHORT TERM...SRW
LONG TERM...SRW
AVIATION...JPH