335
FXUS63 KLMK 241656
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
1256 PM EDT Sun Aug 24 2025

...Updated Aviation Discussion...

.KEY MESSAGES...

* Frontal boundary is passing through the region this morning. Very
  patchy fog is possible through sunrise.

* Pattern change aloft will lead to well below normal temperatures
  to close out August.  Overnight lows will likely drop into the 40s
  in spots.  Record low temperatures may be tied/broken
  Tuesday/Wednesday/Thursday mornings.

* Very dry air is expected in the Wednesday/Thursday time frame,
  dewpoints may drop into the 30s and this may present some fire
  weather issues.

* Consistent signal for possible showers and storms next weekend.

&&

.UPDATE...
Issued at 1111 AM EDT Sun Aug 24 2025

Surface cold front continues to push southward across the area this
morning.  Influx of drier air has pushed into southern Indiana and
far northern Kentucky this morning as dewpoints have dropped into
the upper 50s/lower 60s.  Mid-upper 60 dewpoints were still noted
across much of central and eastern Kentucky.  In the higher dewpoint
air, a decent Cu field is underway.  Under mostly sunny skies,
temperatures were in the mid-upper 70s across the region.  A belt of
80 degree readings were noted from Bowling Green northeastward to
near Richmond.

Current forecast remains in good shape for the afternoon period.
The cold front will continue to push southward and away from
Kentucky later this afternoon and evening.  As this occurs, drier
air to the northwest will continue to build into the region through
the afternoon.  Afternoon highs in the upper 70s to the lower 80s
are still expected.  Some lower-middle 80s will be possible down
across our southeastern sections.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 259 AM EDT Sun Aug 24 2025

The cold front has just entered southern Indiana and will continue
to push through the region this morning, exiting to the southeast by
late morning. A swath of mid-upper clouds is moving east over the
eastern and southern portions of the region, out ahead of the front.
These clouds will limit fog development, though some very patchy fog
is possible. Along the front, a band of low clouds is noted with a
few very isolated showers. These showers will dissipate before
reaching the region given little moisture in the area. As the front
passes, winds will shift to the northwest and become light.
Scattered to broken low clouds will linger behind the front for a
few hours.

By the afternoon, we will be mixing up to 800mb, which will allow
for some gusty winds up to 25mph to mix down to the surface. An
afternoon Cu field will develop, leading to partly cloudy skies.
High temperatures will be in the upper 70s and low 80s over southern
Indiana and low to mid 80s over central Kentucky. Temperatures will
be a few degrees cooler than yesterday, though it will feel more
comfortable as lower dew points move into the region today.

In the evening, skies will clear out and winds will begin to relax.
With ample radiation cooling and better cold air advection,
temperatures will begin to cool more efficiently overnight. Low
temperatures Monday morning are expected to be in the low-to-mid 50s.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 259 AM EDT Sun Aug 24 2025

Monday through Thursday...

An impressive closed upper low over Ontario will continue to spin
and keep broad troughing over the eastern CONUS. This will help to
bring cooler temperatures and drier air from northern Canada into
the lower Ohio Valley. On Tuesday, the closed upper lower will begin
to push east and a shortwave riding along the broader troughing will
move through the Ohio Valley, bringing another shot of cooler and
drier air. Stronger high pressure will remain over the region during
this time, keeping conditions dry and skies sunny.

High temperatures will be in the mid-to-upper 70s and low
temperatures in the low-to-mid 50s through Tuesday. Wednesday will
be the coolest day with low temperatures in the upper 40s and low
50s and high temperatures in the mid 70s as the shortwave pushes
through. Record lows may be in jeopardy through Thursday morning,
with the closest days being Wednesday and Thursday morning at SDF
and LEX. Cold max temperatures will be within a few degrees of
record, but do think these will hold.

Each afternoon, we will see mixing up to about 800-750mb, which will
allow for some dry air mix down each day. Surface dew points will
likely mix down to the upper 30s and low 40s. Some spots might even
see dew points as low as the mid 30s for a few hours. At the same
time, winds gusting up to 20mph will be possible in the afternoons.
These conditions may lead to some elevated fire conditions.

Thursday night through Saturday...

Late this week, broad troughing will begin to push east and ridging
over the western CONUS and slide east. Pesky northwest flow aloft
will bring some disturbances and MCSs from the Plains into the Mid-
Mississippi Valley and possibly the Ohio Valley. We will likely
remain under dry conditions through Friday and into Saturday before
these disturbances begin to impact the region. Will be something to
keep an eye on through the week. High temperatures will likely
remain below normal in the low-to-mid 80s through the end of the
week.

&&

.AVIATION /12Z TAFS THROUGH 18Z MONDAY/...
Issued at 1256 PM EDT Sun Aug 24 2025

Surface cold front continues to push through southern KY this
afternoon.  Behind the front, winds have shifted to the northwest
and speeds of 7-9kts and gusts to 18-19kts will be possible through
the afternoon.  Scattered Cu will be seen through the afternoon
before skies clear out this evening.  VFR conditions are expected
overnight and through the day on Monday.

&&

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

&&

$$

UPDATE.......MJ
SHORT TERM...SRW
LONG TERM....SRW
AVIATION.....MJ