Area Forecast Discussion
Issued by NWS Louisville, KY

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675
FXUS63 KLMK 291722
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
122 PM EDT Sat Aug 29 2026

...Updated Aviation Discussion...

.KEY MESSAGES...

* Dry weather continues for the weekend and into next week.
  Temperatures begin to increase over the weekend and especially
  into next week, with low to mid-90s possible.

* Major Heat Risk possible next week due to the multi-day duration
  of hot temperatures and little overnight relief. Anyone without
  effective cooling or adequate hydration will be susceptible to
  heat illness.

* A few shower and storm chances may return by late week, but
  current confidence is low.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 306 AM EDT Sat Aug 29 2026

Mostly clear morning with some valley fog showing up on satellite
imagery. Any fog this morning will burn off shortly after sunrise.
We`ll have yet another dry and mostly sunny day as sfc high pressure
over the eastern US expands back to the Midwest. Temps today will
reach the upper 80s and lower 90s, with the best chance for those
hotter temps across south-central KY. Dry weather continues tonight
with clear skycover and temps in the upper 60s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 306 AM EDT Sat Aug 29 2026

===== Heat Builds Next Week =====

The prolonged dry streak continues for Sunday and into early next
week as sfc high pressure remains anchored over the mid-Atlantic
region and upper ridging builds over the central US. The main focus
for this time period will be the increasing heat by early next week,
where there is growing confidence in daily high temps solidly in the
90s. Temps on Sunday are forecast to reach the upper 80s to low 90s,
but each subsequent day could be slightly hotter by Wednesday with
potential for mid to upper 90s. Dewpoints will mainly be in the
upper 60s to lower 70s over this time, which fortunately will help
keep our heat indices from becoming oppressive. While it will be
muggy, heat index values are mainly expected to range from the upper
90s to low 100s. The 100-member LREF indicates that there is less
than a 10% chance for max heat index values over 100 for Sunday and
Monday, but those chances start to increase on Monday and Tuesday,
and peak on Wednesday with roughly a 25-55% chance for most. In
addition to the afternoon heat, there will likely be little relief
during the nighttime hours, with overnight lows in the 70s each
night.

Despite dewpoints not being very high, the combination of hot
temperatures, little overnight relief, and the prolonged duration of
heat will likely lead to major heat risk. Major heat risk means that
anyone without effective cooling or hydration will be prone to heat
illness. Probabilities vary by location, but there is roughly a 55%
chance or higher for major heat risk by Tuesday of next week across
the area. That probability increases to at least a 70% chance by
Wednesday. Three or more consecutive days of major heat risk will
trigger an extreme heat risk, which essentially means the entire
population could be susceptible to heat illness if precautions are
not taken, and there could be increased impact to health services.
Based off our forecast temps, we have a generalized 25% chance of
extreme heat risk by Wednesday, though the urban areas are closer to
50%.

While we may not reach criteria heat indices next week, the duration
of this event and subsequent impacts should be considered in making
any Heat Advisory decisions. No plans on this yet, but will need to
consider in following forecast packages.

We remain dry through Wednesday, with our next precip chances not
until Thursday. There is lower confidence toward the end of the week
with temps and precip, but generally expect the 90 degree temps to
continue through the end of next week.

&&

.AVIATION /18Z TAFS THROUGH 00Z MONDAY/...
Issued at 122 PM EDT Sat Aug 29 2026

VFR conditions will persist through the TAF period for all sites.
High to mid level cumulus clouds are developing across the area
currently. These are expected to mostly clear by sunset and through
the night. Winds will remain light and variable tonight and become
southwesterly by tommorow morning.

&&

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

&&

$$

SHORT TERM...CJP
LONG TERM...CJP
AVIATION...CAL