Flash Flood Warning 11, NWS Louisville, KY

Area Forecast Discussion
National Weather Service Louisville KY
146 PM EDT Sun May 24 2026

...Updated Aviation Discussion...

.KEY MESSAGES...

* Areas of patchy fog across the area are possible through early
  Sunday morning, along with a few isolated showers in our far
  southern counties.

* Scattered showers and thunderstorms are possible on Sunday, with
  storms most likely during the afternoon and evening hours. Storms
  may produce locally heavy downpours, lightning, and gusty winds.

* Episodic bouts of showers/storms are expected to continue through
  the rest of the weekend and into at least the middle of next week.
  Localized excessive rainfall may result in flooding in some areas.

&&

.UPDATE...
Issued at 707 AM EDT Sun May 24 2026

POPs were adjusted for the first few hours of the forecast period to
account for ongoing rain showers across the area. Otherwise, the
forecast remains on track, with widespread rain showers and a few
afternoon thunderstorms expected.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 315 AM EDT Sun May 24 2026

With variable sky cover across the area, areas of patchy fog have
developed in locations that have experienced relatively little cloud
cover so far tonight. Light surface winds as well as favorable low-
level moisture have aided in this, but should quickly dissipate
after sunrise as temperatures and winds increase. A few showers and
storms are currently ongoing across the far southeastern portions of
our CWA, with our next round of widespread showers and a few storms
set to begin later this morning.

A weak frontal boundary from a weak surface low over the Great Lakes
extends south towards far western Kentucky Sunday morning.
Meanwhile, an upper-level low develops over eastern Texas with
multiple shortwaves jetting eastward from it towards the Ohio
Valley. Southerly flow will again advect ample moisture over the
area. Current SPC mesoanalysis puts us under an area of 1.25-1.5" of
PW, though a plume of 1.5-1.7" PW over the Mississippi Valley is
trekking northeastward towards us.

With decent ascent and moisture out ahead of the frontal boundary,
widespread showers are expected for most of the day on Sunday.
Mostly overcast skies will limit the extent of diurnal heating,
though with instability expected to increase as the day progresses,
chances for isolated to scattered thunderstorms will also increase.
The wind shear profile at the low levels is rather meager, so while
we are not expecting organized severe convection, any stronger
storms that do develop today could produce heavier downpours,
lightning, and gustier winds. With considerable cloud cover,
temperatures will only get up into the mid 70s Sunday afternoon.

For Sunday night, the coverage of showers and storms quickly
decreased due to the loss of diurnal heating. The frontal boundary
becomes more SW to NE aligned Sunday night, becoming nearly
stationary over central Kentucky by Monday morning. The placement of
this will be important as most of the rainfall in the coming days
will take place along and south of the front, which will be a factor
in how much drought relief we can get.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 315 AM EDT Sun May 24 2026

===== Monday - Wednesday =====

A more active pattern is expected for the upcoming week with daily
precip chances. The synoptic pattern will feature the primary upper
level jet north across Canada, though a cut off low ejecting north
across the southern Plains will support a strong moisture fetch into
the lower Ohio Valley. In addition to that, a frontal boundary will
meander back and forth across the area, leading to a local forcing
mechanism to fire off daily showers and perhaps some storms.

For Monday, the sfc boundary will be pushing through the area as a
cold front and will struggle to clear our area and may stall out
across southern KY by Monday night. Temps in the 70s are expected
throughout the day, with at least scattered to numerous showers and
a chance for isolated storms in the afternoon. The boundary will
continue to sit across the Commonwealth on Tuesday as a stationary
front, slowly meandering northward through the day as the cut off
low over the ArkLaTex region lifts north into the Midwest. This will
open the door for an even better moisture fetch across our area,
with PWATs expected to surge above 1.6". The LREF mean ensemble
ranges around 1.75-1.8" across the region Tuesday morning, and a 25%
chance of exceeding 1.9" across south-central KY. This places us
right at the sounding climo max for this time of year. This will
support heavy, tropical-like rainfall that could drop visibility
significantly and produce local swaths of high precip amounts.

The boundary will be situated parallel to the Ohio River on
Wednesday, which will keep the high-PW environment in place and as
a result numerous to widespread showers and isolated thunderstorms.
Severe chances remain low through the first half of the week, given
model soundings show water-logged profiles and skinny CAPE.
Certainly think we'll have some storms, and heavy downpours given
the PWATs, but shear is marginal without much wind energy over the
area.

===== Thursday into the Weekend =====

Toward the end of the week, a deep upper low will move onshore
across the PNW and meander over the Intermountain West region. At
the same time, an upper shortwave and low will move across the
northeast US. This will sandwich the middle of the US into an upper
ridge, and developing a slanted omega-type pattern. However, at the
sfc, we'll still be dealing with the stationary boundary, which will
continue to support daily precip chances. PoPs for the end of the
week will be slightly higher during the afternoon time frames given
the boost from any daytime heating.

Finally by Friday the boundary should shift far enough south that we
are able to see some slightly drier air begin to filter in from the
north. This is mainly noted over the weekend with drier PoPs for the
northern half of the CWA, but still hang on to some low-end chances
across our south.

As mentioned in the prior discussion, the main impact from this
week's weather pattern should be continued amelioration of drought
across Kentucky. Ensemble most likely rainfall amounts of 1-3" are
expected across the area through Friday, with convection likely
leading to localized swaths well in excess of 3". The LREF depicts a
60-80% chance of exceeding 2.5" of rain for counties south of the
WK/BG Pkwys from today through Saturday of next week. Flooding will
become a greater concern, especially in those aforementioned
convective swaths and across southern IN where the antecedent
conditions are not dry. Otherwise, fairly seasonable temperatures
are expected, with highs in the mid-to-upper 70s and low 80s and
lows in the 60s.

&&

.AVIATION /18Z TAFS THROUGH 00Z TUESDAY/...
Issued at 145 PM EDT Sun May 24 2026

A cold front is approaching the region from the west and there are
showers and a few storms out ahead of it. Numerous showers and
storms will continue to stream over the region until about 3Z. VIS
may drop to 1-2SM at times in heavy rain. MVFR CIGs will continue
over most of the region and begin to lift towards the later
afternoon. Overnight, the cold front will stall over I-65 and CIGs
will begin to fill back in. CIGs will lower to IFR likely and over
the Bluegrass maybe even LIFR and fog. Will continue to monitor this
trend for the next TAF issuance.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...Flood Watch until 11 PM EDT this evening for KYZ029-030-
     034>043-045>049-053>057-065>067.
IN...None.

&&

UPDATE...BEN
SHORT TERM...BEN
LONG TERM...CJP
AVIATION...SRW