-- Discussion containing changed information from previous version are highlighted. --
613
FXUS63 KLMK 091738
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
138 PM EDT Wed Jul 9 2025

...Updated Aviation Discussion...

.KEY MESSAGES...

* Isolated to scattered showers and storms could produce locally
  gusty winds and brief torrential rainfall today, mainly in the
  afternoon.

* Warm and humid all week and into the weekend, with scattered
  showers and thunderstorms expected each day. Organized severe
  weather is not expected.

&&

.UPDATE...
Issued at 1047 AM EDT Wed Jul 9 2025

Scattered light rain or sprinkles are ongoing this morning as we
remain underneath a vort max associated with an upper shortwave.
Cloud cover has helped slow down the diurnal temp curve, with most
stations reporting in the upper 70s and low 80s at this hour. As a
result, expect temps to max out in the mid-80s for most. Scattered
showers and storms remain possible this afternoon, with marginal
CAPE but weak shear available. Higher PWATs are also expected,
potentially near 2 inches for some, so some heavy rainfall could be
possible for this afternoon. Expect the cloud cover to hold for the
day, which will help keep our temps a few degrees cooler today, and
possibly result in weaker destabilization. Overall forecast remains
in good shape, with just some minor tweaking to PoPs given the
current radar trends.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 403 AM EDT Wed Jul 9 2025

Mid level trough will slowly work across the Ohio Valley today with
an associated vort max crossing IN and central KY later this morning
and afternoon. At the sfc, a weak cold front will drop southeast
across IL/IN during the day into the evening. Good moisture
advection ahead of this feature will allow PWAT values to rise to
around 2.00" with a good amount of instability around 2000 J/kg in
the afternoon. All of this along with daytime heating and the muggy
airmass will allow for the development of isolated to scattered
showers and storms. While the best chance is during the afternoon,
we could see some shower/storm activity in the morning as the
shortwave trough and vort max start to work in from the west. It will
remain warm with highs in the mid/upper 80s and dew points near 70.
Once again the lack of shear will keep the activity sub severe with
torrential rainfall, lighting and possible gusty winds as the main
threat.

As the weakening boundary approaches from the northwest and the the
shortwave trough stalls over the Ohio Valley, we could see a few
lingering showers and thunderstorm overnight. Cloud cover will keep
lows in the upper 60s/low 70s.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 403 AM EDT Wed Jul 9 2025

A secondary cold front will drop southward through the Ohio Valley
on Thursday. This boundary is associated with a sfc low that will be
working across the eastern Great Lakes and southern Ontario during
the day Thursday. Front is not expected to make it into our CWA but
we will see slightly drier air filter behind the passing trough axis
as PWAT values drop to around 1.50". While we remain in the warm and
muggy airmass, with continued diurnally driven showers and storms
both Thursday and Friday afternoon. Like the past several days, any
convection will remain unorganized and subsevere producing heavy
rainfall, lighting and potential gusty winds. Highs will also remain
warm in the upper 80s to low 90s.

A series of shortwaves troughs and a frontal boundary will work
across the Great Lakes and the Ohio Valley over the weekend. We will
continue to remain warm and muggy with highs in the upper 80s/low
90s both Saturday and Sunday with dew points in the lower 70s.
Shower and storm chances continue each afternoon with the peak of
daytime heating.

&&

.AVIATION /18Z TAFS THROUGH 00Z FRIDAY/...
-- Changed Discussion --
Issued at 137 PM EDT Wed Jul 9 2025

Cigs have been bouncing between VFR and MVFR today as a low stratus
layer blankets the region. Isolated to scattered showers are also
across the area, which will remain a possibility for all terminals
the rest of the afternoon. By this evening, drier weather is
expected, along with risings cigs. VFR is expected tonight, but with
light winds and low level moisture lingering, some patchy dense fog
may be possible, resulting in a few hours of impacts to vis. We`ll
see terminals return to VFR by tomorrow morning.
-- End Changed Discussion --

&&

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

&&

$$

UPDATE...CJP
SHORT TERM...BTN
LONG TERM...BTN
AVIATION...CJP