512
FXUS63 KLMK 151810
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
210 PM EDT Sun Jun 15 2025

...Updated Aviation Discussion...

.KEY MESSAGES...

*  Patchy, locally dense fog possible this morning.

*  Scattered showers and thunderstorms are expected again today,
   mainly during the afternoon and evening hours. The main threat
   with storms is heavy rainfall and lightning. Localized flooding
   is possible where the heaviest rainfall occurs.

*  Unsettled weather continues next week, with continued rounds of
   afternoon and evening showers and storms expected.

&&

.UPDATE...
Issued at 910 AM EDT Sun Jun 15 2025

The Dense Fog Advisory has expired. Still seeing some reduced
visibility in spots, including Madison IN, but visibility has risen
above 1 mile at our ASOS/AWOS sites. Low stratus will linger through
the morning hours, however. Otherwise, we just have some scattered
light to moderate showers drifting east across the southern half of
the forecast area. No significant forecast changes at this time.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 327 AM EDT Sun Jun 15 2025

Early this morning, most areas across central KY and southern IN are
dry, although a few showers have lingered across south central KY.
Breaks in the mid- and upper-level cloud cover are noted on
nighttime microphysics satellite imagery, with an area of stratus
sinking southward from central IN at this hour. Sfc low pressure
extends along a weak frontal boundary draped over the Ohio Valley
this morning, with a weakening upper level low vertically stacked
atop the sfc wave. As a result, winds are fairly weak through the
boundary layer, especially near the Ohio River. The combination of
weak winds, ample moisture, and patches of clearing will promote the
development of at least patchy fog this morning, and some areas of
dense fog are possible. Will issue an SPS to highlight the fog
potential, although portions of the CWA may need to be upgraded to a
dense fog advisory later this morning. Any fog which develops should
begin to mix out and any low stratus which moves over should lift
during the mid-to-late morning hours as daytime heating increases.

Today, the upper disturbance which has brought enhanced shower and
storm chances over the past few days will continue to weaken and
gradually push toward the Appalachians. The associated sfc front
will continue to linger over the region, and an air mass
characterized by rich moisture with PW values between 1.8-2" will
continue to be present. Once low clouds and fog begin to scatter,
temperatures should warm into the low-to-mid 80s, exceeding
convective temperatures which will generally be in the upper 70s.
Accordingly, scattered showers and thunderstorms are expected once
again late this morning through this evening. MLCAPE values of
around 1200-1600 J/kg will be sufficient for a few vigorous
updrafts; however, 0-6 km bulk shear should only be around 10 kt
given weak flow aloft. This should result in primarily garden-
variety storms once again, with heavy rainfall and localized
flooding again being the primary concern.

Tonight, coverage of showers and storms will greatly diminish after
sunset, setting up another muggy and mild night. A few showers may
develop early Monday morning as the remnants of convection over the
Ozarks this evening approaches from the west. Otherwise, we`ll have
to watch for another round of patchy, possibly dense fog Monday
morning given continued light winds and elevated moisture.
Temperatures should fall into the upper 60s and lower 70s Monday
morning.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 327 AM EDT Sun Jun 15 2025

Monday through Tuesday Night...

As ridging builds across the southwest US tonight into tomorrow
morning, another shortwave is expected to become cut off from the
belt of faster westerlies across the northern US. This disturbance
is expected to move from the Ozarks across the Ohio Valley on
Monday. With a moist, unstable air mass still in place over the
region, another day of afternoon showers and thunderstorms is
expected. Slightly better deep-layer shear will be present on Monday
downstream of the new shortwave; however, continued poor mid-level
lapse rates and skinny CAPE profiles should again limit the severe
storm potential. Heavy rainfall and localized flooding would again
be expected in the heaviest storms. Temperatures should top out in
the low-to-mid 80s Monday afternoon, with lows in the upper 60s and
lower 70s Monday night.

Tuesday has the potential to be a drier day if the shortwave on
Monday can clear the region to the east fast enough, resulting in
slightly drier air working in from the north and west. At this time,
it does look like there will still be a good chance for storms east
of I-65, though this may change depending on the evolution of the
aforementioned disturbance. Temperatures should be fairly similar to
Monday, though there is the potential to warm a few extra degrees if
the drier solutions verify.

Wednesday through Saturday...

A quasi-zonal upper-level pattern will continue into Wednesday, with
additional shortwave troughs sliding quickly across the CONUS.
Medium-range guidance continues to suggest that the most potent of
these systems will cross just north of the Ohio Valley Wednesday
into Thursday, bringing stronger flow aloft and better forcing for
showers and thunderstorms, some of which could be strong. AI/ML
guidance and CIPS analogs continue to suggest that the Wednesday
evening into Thursday morning period could bring and elevated
potential for strong to severe storms, which is consistent with the
SPC Day 5 Outlook. The best forcing and moisture may remain just
north of the area; however, given the amount of lead time, we will
continue to monitor as shifts in guidance could bring the better
severe potential into central KY and southern IN.

Thursday, additional showers and storms are possible as a "cold
front" moves through the region. The air mass behind this front
should be drier, but is unlikely to bring much of a cool down in
temperatures heading into next weekend. In fact, there is fairly
good agreement in medium-range guidance in upper level ridging
building across the eastern US next weekend. This kind of pattern
would suppress thunderstorm chances and support seasonably hot
temperatures, with highs likely making it into the upper 80s and
lower 90s.

&&

.AVIATION /18Z TAFS THROUGH 00Z TUESDAY/...
Issued at 209 PM EDT Sun Jun 15 2025

MVFR ceilings have mostly mixed out, but we do have some lingering
SCT bases below 3 kft early this afternoon. In general, expect
prevailing VFR conditions with a smattering of showers this
afternoon and evening. Thunder probability is fairly low, but cannot
rule out a brief thunderstorm. A quick vis drop is possible in any
small shower or storm, but precip coverage limits confidence in
timing and duration of impacts at any one terminal.

Light winds (5 kt) will be out of the W/NW through sunset before
becoming light and variable, or calm. Skies could briefly partially
clear overnight, allowing some fog to develop. A weak boundary will
linger near the Ohio River. It does appear likely we will see
another round of low-end MVFR stratus, and possibly brief IFR,
Monday morning.

&&

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

&&

$$

UPDATE...EBW
SHORT TERM...CSG
LONG TERM...CSG
AVIATION...EBW