441
FXUS63 KLMK 121932
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
332 PM EDT Fri Jun 12 2026

.KEY MESSAGES...

* Multiple chances for showers and storms are expected this weekend.
  Some strong to severe storms will be possible Saturday afternoon
  into Sunday, with gusty winds being the main severe hazard.
  Isolated flash flooding will be possible if training of storms
  occurs.

* Cooler and drier weather returns Sunday night through early next
  week.

* Another potent storm system lurks on the horizon next Wednesday
  night into Thursday, with strong storms, heavy rainfall, and
  unusually strong non-thunderstorm winds possible. Monitor
  the latest forecasts over the next several days.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 332 PM EDT Fri Jun 12 2026

This Afternoon through Tonight...

At this hour, a cold front extends from SW to NE across Kentucky,
with clearing skies and drier air located along and north of the
Ohio River. For the rest of this afternoon and evening, the front is
expected to slowly sink to the southeast before becoming quasi-
stationary near the KY/TN border tonight. Along and south of the
front, dewpoints in the upper 60s and low 70s will allow for some
instability for showers and storms to develop this afternoon and
evening; however, weak mid- and upper-level forcing and shading from
convection over the TN Valley will limit this potential.

Lower dewpoints will continue to sink south across KY tonight, with
winds becoming light and variable after sunset. How quickly/if this
llvl moisture can get out of the area will determine the potential
for fog development tonight into Saturday morning, as light winds
and clearing skies would otherwise favor fog development. 12Z HREF
probabilities of less than 3 mile visibilities are highest south of
the WK/BG Parkways, so we`ll have to watch these areas closest,
especially in the valleys. Lows Saturday morning should be cooler
than the past few nights given the lower dewpoints, ranging from the
upper 50s/low 60s north of I-64 to the mid 60s along the TN border.

Saturday - Sunday Night...

Over the first part of the weekend, synoptic scale zonal flow is
expected across much of North America as an upper low over Ontario
and a broad upper high across the southern US/MX prevail. However,
by Saturday evening, an upper level jet max ejecting across the
northern US Rockies should lead to amplification of a shortwave over
the Dakotas and into the Midwest Saturday night into Sunday.
Downstream from this developing trough, return flow should cause the
moist, unstable air mass to lift gradually back to the northeast
across the lower Ohio Valley over the next 36 hours before a
secondary cold front moves through during the day on Sunday. Between
Saturday afternoon and FROPA Sunday evening, this should result in
additional chances for showers and storms across the area.

On Saturday, we`ll have to monitor upstream convection over the
Missouri Valley/Ozarks Saturday morning. If this activity can
survive, it could push into southwest IN/western KY during the
afternoon and evening hours Saturday. Temperatures warming into the
mid 80s tomorrow afternoon should provide some fuel for storms;
however, HREF guidance suggests that a NE-SW gradient in dewpoints
will lead to decreasing instability the farther northeast you go. As
a result, would expect the main potential for strong storms that
could produce gusty winds to be in southern and western portions of
the CWA tomorrow afternoon.

If the afternoon/evening convection develops as expected, we will
likely have a lull in activity over the area for a portion of the
evening and early overnight hours Saturday night. During this time
period, increasing return flow will support increasing llvl moisture
into the region, bringing a pool of 1000+ J/kg MLCAPE further into
central KY and southern IN. By early Sunday morning, ongoing
convection closer to the front is expected to drop toward the
region, bringing a second wave of potentially strong to severe
storms. Once again, strong wind gusts will be the main severe
threat, with the severe potential decreasing as storms push to the
east and outrun the greatest instability Sunday morning.

After this second chance for storms, it may still be another 6-8
hours before the sfc cold front pushes through, bringing an end to
the shower/storm potential. Given the amount of uncertainty with
preceding waves of convection, forecast confidence in the storm
threat later in the day on Sunday is low, but if preceding
convective contamination isn`t too great, another potential for
strong storms would exist Sunday afternoon. All in all, given
several potential rounds of storms this weekend, there could be a
few areas that see enough training of heavier rain for minor
flooding concerns. With that being said, storm motions should be
considerably faster than the setup we had earlier this week, so it
will likely take multiple rounds of storms for flooding to be
realized.

By Sunday evening, things should begin to quiet down from west to
east across the area as the second cold front pushes through,
bringing cooler and drier air into the region.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 332 PM EDT Fri Jun 12 2026

Monday - Tuesday Night...

An unseasonably amplified wave pattern is expected to establish
itself over North America during the first half of next week, with
deep upper troughing over the eastern US and ridging along the west
coast. Surface high pressure is expected to sink into the southern
Plains, with semi-stationary sfc low pressure expected to meander
across eastern Canada.

This pattern, more reminiscent of January than June, will allow for
cool and dry flow across the Ohio Valley and much of the eastern US
over the Monday and Tuesday time period. Negative PW anomalies will
settle across the Ohio Valley on Monday and are expected to continue
through Tuesday before gradual moisture return occurs later in the
period. Temperatures are expected to be below climatological
normals, with highs in the mid-to-upper 70s on Monday and upper 70s
and low 80s on Tuesday. Lows will be even more refreshing given the
recent humid weather; widespread lows in the 50s are likely Monday
morning through Wednesday morning.

While most of this period should remain dry, there could be enough
lingering moisture with cyclonic flow aloft for isolated showers,
particularly Tuesday into Tuesday night. However, at this time,
coverage is expected to be fairly sparse (if any at all), and
significant impacts appear unlikely.

Wednesday - Thursday Night...

An active, potentially impactful period of weather is possible
during the mid-to-late week period next week. The broad upper low
over eastern Canada is expected to retrograde slightly by next
Wednesday, with a series of shortwave troughs and vort lobes sliding
along the southern flank of the low. A particularly strong shortwave
coupled with an upper jet max is expected to eject across the
Canadian Rockies and into the northern Plains Tuesday night into
Wednesday, leading to sfc cyclogenesis Wednesday into Wednesday
night over the upper Midwest and lower Great Lakes. This area of low
pressure is expected to become anomalously deep, with ECMWF ensemble
mean MSLP near or below the 1st percentile of model climatology. In
response, an unusually strong wind field will be present over the
region, with Extreme Forecast Index values for winds and gusts
exceeding 0.8 Wednesday into Thursday.

As the low deepens to the north of the region, strong return flow
(ECM 850 mb mean winds exceed the 99th percentile) will bring
moisture and instability back into the region from the southwest.
With that being said, moisture return is still a bit uncertain given
the limited amplitude of the upper-level wave. The combination of an
unusually dynamic environment and some instability may lead to a
favorable setup for organized strong to severe storms Wednesday
night into Thursday. Medium-range AI/ML severe guidance shows the
strongest signal between over IL/IN/OH; however, this is close
enough that it bears watching over the next several days.

At this lead time, there is still a lot of forecast uncertainty, but
there is increasing likelihood in at least showers and storms, as
well as windy conditions for June during the Wednesday-Thursday time
period. Temperatures should moderate toward climatological normals,
with highs in the low-to-mid 80s and lows in the 60s and low 70s.

&&

.AVIATION /18Z TAFS THROUGH 00Z SUNDAY/...
Issued at 143 PM EDT Fri Jun 12 2026

A cold front is slowly moving across the area this afternoon. In the
vicinity of the front, MVFR CIGs have been observed, and occasional
periods of MVFR CIGs will be possible over the next few hours before
deeper mixing should lift most of the cu field to 3-4 kft. Winds are
expected to veer from W/SW to NW this evening, with wind speeds
easing around sunset. Overnight, VFR conditions are expected to
continue until the pre-dawn hours Saturday, when lingering low-level
moisture may try to build into patchy fog at LEX/BWG/RGA. Confidence
in this is low, especially at LEX/RGA, so while IFR or lower VIS is
possible, will carry 6SM VIS until there is greater confidence. By
the end of the forecast period, light S/SE winds are expected to
return, with VFR conditions expected at all sites by mid-Saturday
morning.

&&

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

&&

$$

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