716
FXUS63 KLMK 071042
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
642 AM EDT Sun Jun 7 2026

...Updated Aviation Discussion...

.KEY MESSAGES...

* Isolated showers and storms are possible today, mainly across
  southern Indiana and southern Kentucky. Central Kentucky should
  stay warm and dry.

* Unsettled weather with localized areas of heavy rainfall and flash
  flooding are possible in KY and southern IN Monday - Tuesday
  midday.

* Daily rain chances with muggy conditions are expected to last
  through the end of the week.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 320 AM EDT Sun Jun 7 2026

Interesting setup across the region today as we sit under an upper
ridge axis stretching from the SE CONUS up through the western Great
Lakes. This feature is bookended by two separate shortwaves, one
moving into the mid Mississippi River Valley, and the other other
over New England. At the surface, a stalling frontal boundary
trailing from the New England system will settle across central
IL/IN/OH, possibly down to the Ohio River by this evening. Normally,
an upper ridge would keep our area dry, and this will mainly be the
case. However, we will see enough of a trigger from the frontal
boundary across our north for perhaps a few showers or a storm, and
across our SW CWA as deeper moisture ahead of the upstream shortwave
starts to make it into our area. Kind of a squeeze play scenario as
we sit between two synoptic features. Will keep some low chance pops
across our northern CWA (I-64 north), and down along the TN border
across our SW CWA to account. The central part of the CWA looks to
stay dry.

Will have at least some isolated t-storm chances in these areas as
well as HREF data shows a 20-30% chance of up to 1000 J/KG of ML
CAPE. No real deep layer shear to speak of, as mentioned in the
previous discussion, so no strong to severe threat really expected.

As we move into tonight through Monday, any activity associated with
the stalled frontal boundary will steadily diminish with the loss of
heating, and focus will then shift to our western CWA as the main
deep moisture plume begins to move in ahead of the slow moving
upstream shortwave. Most of the shower and storm coverage will be
along and west of I-65, and across southern KY before sunrise on
Monday. Then, expect numerous showers and storms over the entire CWA
through the day. Not much has changed with the thinking through
early week as this setup checks several boxes that point toward a
localized heavy rainfall threat through Monday, and likely into
Tuesday. Very high PWATs (~2"), slow storm movement thanks to weak
deep layer flow, tall/skinny CAPE profiles, and a deep freezing
level above 14K feet. WPC Slight Risk looks good for much of the
CWA, and now that Monday is in the range of the 07/00z HREF, we are
seeing that signal in the PMM data for some localized higher amounts
outside of the lower basin averaged QPF values. Luckily, the PMM
values don`t go as high as the HREF Max member, but will keep an eye
on trends. We may have to consider a Flood Watch as we approach the
Monday through Tuesday time frame. Wouldn`t expect widespread flood
problems, however could see a scenario where several localized
flooding issues arise if repeated slow moving heavy rainers impact
certain areas.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 320 AM EDT Sun Jun 7 2026

=====Tuesday - Wednesday Night=====

Some consensus is building between mid-range trends in ensemble
means, pointing towards a mid level shortwave trying to erode the SE
high on Tuesday. This means there will be a broad lifting mechanism
for showers and weak storms Tuesday night. This is an interesting
set up as the shortwave tries to merge with the overall mid level
flow within pronounced ridging over the eastern US. Models have
struggled with the strength of the SE high. The trend now appears
that this shortwave will act to weaken the ridge, despite strong
subsidence at 500 mb, with heights approaching the 90th percentile.
What we will have working in our favor for widespread rainfall are
PWATs ranging 1.8-2" -or higher- over KY on Tuesday behind an
advancing warm front. Any kind of forcing could easily create
locally heavy downpours Tuesday afternoon as the shortwave slowly
trudges eastward with weak synoptic flow over the Ohio Valley. This
is further supported by the Marginal Risk for excessive rainfall
issued by the ERO on Tuesday.

Overall, this means Tuesday features continued southwest flow
lingering into the evening hours. Widespread showers and weak storms
will continue in the morning and afternoon before slowly ending west
to east Tuesday evening. From the continued presence of cloud cover
and rain chances, Tuesday`s highs will be a bit cooler than
previously thought, in the low to mid 80s. With a tropical air mass
in place and with no strong flow to push higher PWAT values and dew
points away, we will likely see continued daily rain chances through
mid week. Morning lows with this moist air mass overhead will be
well above normal as well, nearing record warm lows in some areas
which will be monitored as needed in the upper 60s to mid 70s
through Wednesday.

Guidance becomes very uncertain with Wednesday`s rain chances, with
decent spread in the long range daily rainfall totals. 25-75th
percentiles have a 0.5+" disagreement with one another, indicating
the uncertainty with the placement of the original shortwave moving
through and the advancement of stronger trough swinging down from
central Canada. Should more rain showers stick around, highs on
Wednesday will be cooler in the low to mid 80s but for now,
forecasted highs will be near 90 degrees.

=====Thursday - Saturday=====

As mentioned before, the original shortwave may finally move
eastward far enough to allow temperatures to rebound into the upper
80s to low 90s. Though with PWATs remaining higher in the 1.5-1.75"
range, afternoon storms will return. By Thursday night into the
weekend, a stronger trough will be swinging down from central Canada
which may serve to bring more widespread rainfall Friday into
Saturday. If this trough remains too far north, then regular
diurnally driven storms will continue. Highs will remain in the mid
to upper 80s by then.

&&

.AVIATION /12Z TAFS THROUGH 18Z MONDAY/...
Issued at 642 AM EDT Sun Jun 7 2026

VFR conditions expected to prevail for much of this TAF cycle,
although some deteriorating conditions in rain showers and/or
lowering ceilings could occur later today into tonight as a slow
moving disturbance moves toward our region, and a weak frontal
boundary sags southward toward the Ohio River. The main theme will
feature variable mid to upper sky cover with light SSW-SSE winds
between 5 and 10 mph. Can`t rule out a few sprinkles or light
showers at BWG or SDF late morning into early evening, but not real
high confidence here. Also, there could be some lower ceilings that
move into BWG/HNB by the end of this forecast cycle late tonight.

&&

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

&&

$$

SHORT TERM...BJS
LONG TERM...BKF
AVIATION...BJS