874
FXUS63 KLMK 161955
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
355 PM EDT Sat May 16 2026

.KEY MESSAGES...

* This evening and tonight, strong to severe thunderstorms are
  possible, with the SPC putting us under a Slight Risk for severe
  weather. Damaging winds and isolated hail are the primary concerns.

* Temperatures are expected to warm into the mid 80s to low 90s for
  Sunday and into the beginning of next week. Some daily max
  temperature records could be challenged.

* Tuesday and Wednesday, more showers and thunderstorms ahead of a
  cold front, dropping temperatures back to near normal for later
  this week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 355 PM EDT Sat May 16 2026

Clearing skies across the area following this morning`s showers and
thunderstorms has allowed temperatures to rapidly climb into the
upper 70s/low 80s. Temperatures will continue to grow into the low-
to-mid 80s over the next few hours before a mid-level disturbance
and a MCS moves through the area this evening. With robust southerly
flow in place, dew point values have also rapidly rose into the mid-
60s, allowing for ample moisture as we prepare for another round of
potentially strong-to-severe thunderstorms this evening.

Instability overall has quickly rose over the past few hours, with
SBCAPE values ranging from 1500 to 2000 J/kg currently, and MLCAPE
and MUCAPE values in the 1500-2500 J/kg range. With the strong
diurnal heating, recent model guidance has us mixing up to near the
750 mb level, with fairly steep low-level lapse rates also present.
As a result, this has also help increase our DCAPE values to over
700 J/kg, increasing as you go further south. An area of more robust
bulk shear (>30 kt) has developed in SW Kentucky and will shift
northeastward in the coming hours, helping set up our next round of
showers and storms.

With our cloud bases from this morning and afternoon remaining
fairly elevated, our main concerns for this upcoming round will
mostly be damaging winds and isolated severe hail. The cells over
time may form into a bowing/linear segment over time depending on
the evolution of the system, which would then quickly transition our
threat to mostly severe winds. With the wind shear that would be in
place, a brief spin up tornado cannot be ruled out, but is very
unlikely given the higher cloud bases/LCLs in place. This system
will slowly move off the northeast during the overnight hours,
exiting by Sunday morning. While near-surface capping will quickly
develop after sunset as a result of an intensifying LLJ and the loss
of diurnal heating, elevated instability will remain in place and
allow the storng-to-severe threat to continue into the night for any
storms that persist.

&&

.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 355 PM EDT Sat May 16 2026

Sunday - Monday...

Once the system departs to the east early Sunday, conditions for the
next couple of days are going to be dry and very warm. With the
ridge over the eastern CONUS becoming more amplified and the center
of the surface high residing over the Atlantic, persistent southerly
flow will allow ample WAA to move over the region. Temperatures will
be in the upper 80s both days, with some locations getting above 90.
LREF guidance gives most areas south of the Ohio River a 35-50%
chance of reaching 90 on Sunday, with probabilities increasing to 40-
55% on Monday. Dew points both days will be in the low-to-mid 60s,
so expect rather muggy conditions. A few weak perturbations may pass
over the far western portions of the CWA, providing a quick shower
or storm, though chances right now are currently low (10-20%).

Monday Night - Wednesday Night...

Off to the west, a robust shortwave trough ejects from the central
Plains towards the Upper Midwest. The cold front from its associated
surface low trails to the south and west, slowly moving towards the
Ohio Valley and arriving late Tuesday. With southerly flow
continuing ahead of the front, temperatures during the afternoon
will again be very warm, with highs in the upper 80s/near 90. Once
the front moves in, more widespread showers and scattered
thunderstorms will continue through late Wednesday as the front
slowly drifts southward. With the front overhead on Wednesday, a
semi-decent temperature gradient will be in place, with southern
Indiana in the upper 70s and south central Kentucky in the upper
80s.

Thursday - Saturday...

Rain chances will slowly decrease as the front departs to the south,
and broad northerly flow will allow afternoon temperatures to be
closer to normal for this time of year with highs in the mid 70s.
The reprieve from drier conditions does not last long as a shortwave
trough develops over the southern Plains and ejects to the
northeast. This will help the previously mentioned frontal boundary
lift back northward and set us up for another round of showers and
occasional storms that would last until the end of the forecast
period. Long-range guidance is not as certain on how far northward
the front will lift given the preceding surface high pressure over
our area to the north of the front. Temperatures each of the three
days will be in the mid-to-upper 70s, with some places approaching
80 on Saturday.

&&

.AVIATION /18Z TAFS THROUGH 00Z MONDAY/...
Issued at 210 PM EDT Sat May 16 2026

A brief break from this morning/early afternoon`s showers and
thunderstorms is currently ongoing for most places, with the next
round expected to begin around 21z. Ceilings and visibilities should
remain above VFR, but a heavier downpour could very briefly reduce
ceilings and visibilities. Coverage of showers and storms will
decrease after 0z, though a PROB30 was included across the terminals
given the scattered nature in recent guidance. Occasional increased
gusts are possible this afternoon and evening, quickly diminishing
after sunset. Sunday will have dry and VFR conditions, with
southerly gusts increasing during the afternoon hours.

&&

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

&&

$$

SHORT TERM...BEN
LONG TERM...BEN
AVIATION...BEN