287
FXUS63 KLMK 242355
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
755 PM EDT Sun Aug 24 2025

...Updated Aviation Discussion...

.KEY MESSAGES...

* Breezy conditions expected through sunset this evening.

* Significant pattern change aloft will lead to well below normal
  temperatures for the upcoming week.  Overnight lows will drop into
  the 40s in places.  Record low temperatures may be tied/broken
  Wednesday and Thursday mornings.

* Dry air mixdown is expected on Wednesday and Thursday which will
  allow afternoon dewpoints to drop into the 30s and this may lead
  to elevated fire danger

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 243 PM EDT Sun Aug 24 2025

Well advertised cold front continues to sink southward across
southern Kentucky this afternoon.  In its wake, sunny skies and
breezy northwest winds were noted across the region.  Afternoon
temperatures ranged from the upper 70s over southern Indiana and
northern Kentucky to the lower 80s across much of south-central and
southern Kentucky.

For the remainder of the afternoon hours, no significant weather is
expected.  Breezy northwest winds will continue through sunset and
then the winds are expected to simmer down.  Afternoon highs will
top out in the upper 70s to the low-mid 80s before cooling into
upper 60s later this evening.  For the overnight period, mostly
clear skies are expected.  With cold advection solidly in place,
look for lows to drop into the lower 50s across southern Indiana and
portions of northwest KY.  Lower-middle 50s are expected elsewhere.

Sunny and pleasant conditions are expected for Monday as high
pressure will continue to build into the region from the northwest.
Daytime highs will be well below normal for late August with highs
in the mid 70s across southern Indiana and much of north-central and
east-central Kentucky.  Some upper 70s will be possible down along
and south of the Cumberland Parkway.  Clear skies and light winds
are expected for Monday night with lows bottoming out in the lower
to middle 50s.  A few upper 40s can`t be ruled out in southern
Indiana and our typical cold spots.  Current forecast data suggests
that records at the climate sites will be safe Tuesday morning.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 243 PM EDT Sun Aug 24 2025

Tuesday through Thursday Night...

Overall, not much change in the forecast thinking through this time
frame.  Upper level pattern across the CONUS will remain quite
amplified during the period with a upper trough axis situated in the
eastern US with a ridge out across the western US.  Deep north to
northwest flow will be seen across the Ohio Valley with the source
region of this air coming from the high latitudes of Canada.  High
pressure will continue to build into the region on Tuesday and then
pass through the area Tuesday night and Wednesday morning resulting
in good radiational cooling across the area.

Highs on Tuesday will be similar to Monday with readings in the
middle 70s across southern Indiana and much of north-central and
east-central Kentucky.  Some upper 70s will be possible down across
southern Kentucky.  With good radiational cooling expected Tuesday
night, overnight lows will likely dip into the upper 40s to the
lower 50s and we have good shot at breaking or tying record lows at
some of our climate sites.

Dry conditions will continue across the region for Wednesday and
Thursday.  With high pressure situated across the region, model
soundings suggest that we`ll get good dry air mixdown Wednesday
afternoon and again on Thursday afternoon.  Should this occur,
dewpoints both afternoons will likely drop into the mid-upper 30s,
which is relatively rare for late August.  In addition, the mixdown
will also result in a diurnal increase in the winds during the
afternoon.  The combination of low afternoon RH and continued drying
of fuels may lead to an elevated fire weather risk across the region
for Wednesday and Thursday.

Highs on Wednesday will be in the mid-upper 70s with mainly upper
70s to near 80 for Thursday.  Lows Thursday morning will drop back
into the lower 50s, but our valleys and the good radiational cooling
sites probably will drop into the upper 40s again and we may
break/tie some low temperature records at a few of our sites.  Lows
Thursday night will not be as cold with readings mainly in the lower
50s.

Friday through Sunday...

The upper level pattern across the CONUS will modify a bit as we
close out the week and head into the holiday weekend.  Broad upper
level trough over the eastern US is forecast to shift eastward with
time while a series of MCSs moves from the southern Plains into the
lower-MS valley region.  Most of the activity looks to remain to our
southwest for Friday and into Saturday.  However a weaker
perturbation within the flow aloft coming through the upper Ohio
Valley may spark a few showers across the region Friday.  Given the
model spread, overall confidence here remains low, but will keep
some low PoPs (<14%) in for Friday.

For Saturday and Sunday, the upper trough axis over the eastern US
may deepen once again while upstream ridging develops out across the
western CONUS. Will need to keep an eye on any perturbations coming
down within the northwest flow.  The Euro remains dry through this
period, while the GFS has a perturbation that comes through late
Sunday and into Monday which could yield some showers across the
region.

Highs during the period will remain slightly below normal with highs
in the upper 70s to the lower 80s and overnight lows in the upper
50s to the lower 60s.

&&

.AVIATION /00Z TAFS THROUGH 06Z TUESDAY/...
Issued at 754 PM EDT Sun Aug 24 2025

Gusty northwest winds will diminish with the setting sun along with
the clearing of mid-level CU. Winds will become light and skies
clear as high pressure over the Northern Plains and Dakotas
continues to build in over the region. Flight categories remain VFR,
the only impacts will be gusty afternoon winds out of the northwest
again tomorrow afternoon and another day of mid-level Cu developing
over the area.

&&

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

&&

$$

SHORT TERM...MJ
LONG TERM...MJ
AVIATION...BTN