061
FXUS63 KLMK 151847
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
247 PM EDT Wed Jul 15 2026

.KEY MESSAGES...

* Dry weather for most today, though there is a chance for an
  isolated afternoon or evening storm mainly over southern Kentucky.
  Scattered afternoon thunderstorm chances (30-50%) return Thursday
  afternoon and evening.

* Rain and thunderstorm chances peak Friday into Saturday,
  especially during the afternoon and evening hours. Slow-moving
  storms will be capable of locally torrential rainfall, lightning,
  and gusty winds.

* Outside of storms, heat indices will peak in the 97-103 degree
  range each afternoon through at least Friday. Minor to moderate
  heat risk is possible, mainly affecting vulnerable populations
  sensitive to heat, especially those without cooling/hydration.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 245 PM EDT Wed Jul 15 2026

At 2pm EDT, temperatures across central Kentucky and southern
Indiana were generally in the upper 80s degF, with a couple
spots touching 90. Given dewpoints in the low 70s, heat indices
(or "feels like" temperatures) were in the mid to upper 90s,
making for another muggy day.

Mid-level water vapor imagery reveals a pronounced dry slot across
the region associated with the subsidence of the ridge, and a cut-
off low continues to meander across the southwest. Meanwhile,
moisture streams from the eastern side of the low, keeping much of
the region under a moist airmass. With just enough lift from the
nearby low and strong diurnal heating, the highest convective
chances remain confined mainly to southwest KY. Isolated showers are
possible this afternoon and with elevated PWATs around 1.75-2", any
shower that develops will have ample moisture to work with for a
quick, heavy downpour. While model soundings indicate moderate
instability is available across the region (SBCAPE values from 2500-
3000 J/kg), 0-6km bulk shear weakens through the afternoon, so
showers will be slow-moving and efficient rain-producers.

By Thursday, the upper-level ridge begins to weaken, allowing more
coverage for afternoon pop-ups. PoPs range from 30-50% in the
western half of the region, and similarly to Wednesday, moderate
instability and weak shear are expected to keep these pop-up
showers` main threats contained to locally heavy downpours and gusty
winds. Temperatures remain seasonably warm as we switch to a
southwesterly flow, and with highs in the upper 80s to low 90s and
dewpoints in the 70s, heat indices will likely approach 98-102
degF. Due to nocturnal cooling, showers and storms will
diminish throughout the evening/overnight, and temperatures are
expected to fall back into the lower 70s across the region.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 245 PM EDT Wed Jul 15 2026

===== Friday - Saturday =====

A subtle mid-level shortwave disturbance is forecast to begin the
period over the Mid-Mississippi Valley. This feature will meander
anticyclonically around the mid-level ridge axis and across the
Lower OH Valley through Saturday. This feature will help draw deeper
moisture into the region, with ensemble mean PW values increasing to
1.9-2.0 inches. By Saturday, we also see a much weaker ridge aloft
(over our region) with the amplification of the upper level ridge
over the Rockies and the downstream trough diving southeast over the
Great Lakes. A sfc low is forecast to track east across portions of
the Great Lakes, with an attendant cold front dropping south through
the Upper Midwest.

Sfc dewpoints in the low to mid 70s look to be common both Friday
and Saturday. At least moderate destabilization of the warm, moist
airmass appears likely both days. Given weak forcing and much less
subsidence aloft, scattered to numerous showers and storms are
expected each afternoon and evening. Very weak deep-layer shear and
low-level forcing will support a pulse convective mode. Outflow
boundary interaction may locally enhance storm coverage and threats.
The primary threats are locally torrential rainfall, strong wind
gusts, and lightning. Very slow-moving cells capable of torrential
rainfall may lead to isolated flash flooding. Outside of storms,
afternoon temperatures will rise into the 85-90 degree range.
Morning lows will reach the lower 70s.


===== Sunday - Next Week =====

By late Saturday night, low pressure is forecast to be deepening to
the northeast across New England with a sfc cold front dipping south
into the Lower OH Valley. A deeper upper level trough will continue
to be carved out over the northeastern CONUS heading into Sunday.
We`ll start to see some drier air aloft advect into the region from
the northwest. The cold front pushing through will keep a chance (30-
50%) for rain in the forecast for central and southern KY through
Sunday.

Monday looks much drier overall in the wake of Sunday`s cool front.
Another digging upper level trough and deepening sfc wave across
Ontario may then drag another cold front into the region by late
Tuesday. This keeps a low chance (20-30%) of rain in the forecast
for Tuesday, but confidence in the details is low at this time
range.

&&

.AVIATION /18Z TAFS THROUGH 00Z FRIDAY/...
Issued at 143 PM EDT Wed Jul 15 2026

High pressure will maintain light winds and dry weather throughout
the forecast period. Diurnal cu around 4kft should dissipate this
evening, which will result in a favorable environment for patchy fog
by 08-12z; this remains in the forecast via a tempo group at the
terminals with the highest confidence (20-30%), i.e., HNB, LEX,
and RGA.

&&

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

&&

$$

SHORT TERM...REJ
LONG TERM...EBW
AVIATION...JRB