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629
FXUS63 KLMK 141957
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
357 PM EDT Mon Jul 14 2025

.KEY MESSAGES...

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* Remaining hot and humid this week with more scattered rain and
  storm chances each day. Heavy rain, gusty winds, and lightning
  will be the main threats.
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&&

.SHORT TERM /THROUGH TONIGHT/...
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Issued at 356 PM EDT Mon Jul 14 2025

This Afternoon and Evening...

Scattered clusters of showers and thunderstorms have developed
across the area this afternoon, with the stratus layer that was
along a decaying front now scattering out into a stratocu field over
central KY and southern IN. Temperatures have warmed into the mid
80s in most areas, with dewpoints typically in the low-to-mid 70s as
low-level moisture pools along the front. This has allowed for
modest amounts of instability, generally between 1500-2000 J/kg
MLCAPE on latest SPC mesoanalysis. Latest hi-res guidance suggests
that shower/storm coverage should remain isolated to scattered this
afternoon, especially as the mid-level wave associated with the sfc
front lifts to the north and east. The greatest coverage of showers
and storms according to CAMs will be over southern KY, with coverage
decreasing around sunset as we lose sfc-based instability.

Tonight...

The muggy air mass overhead will keep temperatures mild tonight as
low-level moisture settles after sunset. While an isolated shower is
possible across southwestern portions of the CWA, most of the area
should remain dry overnight. The main forecast challenge will be
if/how much fog develops tonight. While at least patchy fog looks
like a good bet for rural areas and valleys, there is still some
uncertainty if lingering cloud cover will keep fog from being more
widespread. For what it`s worth, the strongest fog signal in the 12Z
HREF guidance extends across the Bluegrass region and into eastern
KY, with more of valley fog signal present elsewhere. Lows Tuesday
morning should end up in the low 70s in most locations, with a few
upper 60s possible in the cooler valleys.

Tuesday...

No significant changes are expected in the large scale pattern for
tomorrow, with the warm and humid air mass remaining in place. Short
range models depict another convectively-enhanced mid-level
disturbance moving from the ArkLaTex to near the confluence of the
Ohio and Mississippi River tomorrow. This should provide some
additional support for showers and thunderstorms during the
afternoon, with several hi-res models showing greater coverage in
the vicinity of the MCV. Deep-layer shear values will still be
fairly weak on the order of 15 kt, so mostly disorganized showers
and storms are expected, with water-loaded stronger cells producing
gusty winds, heavy rainfall, and lightning. While cells should move
at around 15-20 mph, areas which have greater residence time of
heavy rain could see localized flooding. Highs on Tuesday should be
fairly similar to today in the upper 80s and lower 90s.
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&&

.LONG TERM /TUESDAY THROUGH MONDAY/...
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Issued at 356 PM EDT Mon Jul 14 2025

Medium-range guidance consensus continues to show a fairly static
synoptic pattern late this week and through the weekend as a belt of
faster zonal flow continues across the northern US and southern
Canada while ridging shifts back and forth between a typical Bermuda
high setup and a southern Plains setup. With no large-scale forcing
to shift the pattern, like the way the previous forecast describes
the "rinse and repeat" setup, as each day should be fairly similar
weather-wise. In general, expect seasonally hot and humid conditions
with temperatures ranging from the upper 80s to the mid 90s for
highs and low-to-mid 70s for lows. With dewpoints remaining in the
low-to-mid 70s through the extended period, afternoon heat indices
should peak in the upper 90s and lower 100s, with the highest heat
indices expected Thursday afternoon. While conditions should be
fairly uncomfortable each afternoon, expected heat indices aren`t
out of the ordinary for mid July and should be below advisory
criteria.

Daily scattered shower and thunderstorm chances will peak in the
afternoon and evening and diminish for the nighttime and morning
hours. With the band of stronger mid- and upper-level westerlies
staying well to the north, wind shear will remain weak, and
convection will remain largely disorganized. Coverage will likely be
variable from day-to-day as increased coverage would be expected in
the vicinity of smaller-scale shortwaves in the zonal flow aloft. In
general, garden-variety showers and storms with localized gusty
winds and heavy rainfall can be expected each day. The main threats
from these storms should be localized flash flooding due to longer
residence time of heavy rainfall.
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&&

.AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 152 PM EDT Mon Jul 14 2025

Scattered showers and isolated thunderstorms are currently forming
across the area and are expected to continue this afternoon,
gradually diminishing around sunset. Outside of showers and storms,
ceilings should remain VFR through this evening. With a weak front
over the area, winds will be light and variable between the SW and
W/NW through around sunset.

Tonight, moisture in the vicinity of the front and light/calm winds
will promote the development of fog and/or low stratus. Confidence
is low-medium on how much categories will fall, with the main window
for fog development being between 15/07-12Z. While some guidance is
showing IFR or lower visibilities, due to low confidence, will
advertise MVFR conditions for now. By mid-morning, any fog should
lift into a stratocu layer, with brief MVFR CIGs possible as the
moisture mixes upward.

&&

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

&&

$$

SHORT TERM...CSG
LONG TERM...CSG
AVIATION...CSG