132
FXUS63 KLMK 180556
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
1256 AM EST Tue Nov 18 2025

...Updated Aviation Discussion...

.KEY MESSAGES...

* Widespread rain and scattered storms expected Tuesday. A few
  stronger storms could produce small hail and a brief spin-up
  tornado.

* Active weather pattern will bring multiples chances for rainfall
  Thursday through Saturday.

* This weekend through early next week continues to trend drier.

&&

.UPDATE...
Issued at 859 PM EST Mon Nov 17 2025

Regional radar mosaic shows a cluster of storms moving across LSX
and ILX CWAs this evening, which is located on the nose of the 850mb
jet core and WAA regime. The sfc low is located over northeastern
Kansas for now, with the warm front extending to the southeast and
the cold front trailing to the south. We`ll see the warm front swing
northward tonight into southeast MO, amplifying our isentropic lift
across KY and IN, and resulting in radar echoes spreading out across
our forecast area during the early morning hours. We should remain
dry before midnight, and perhaps longer into the night as model
soundings indicate rather dry air below 800mb.

Overall forecast remains in good shape, with only some tweaks to the
grids to blend in the 00z guidance.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 305 PM EST Mon Nov 17 2025

A low pressure system will approach the region in the overnight
hours. Ahead of the warm front, isentropic lift will allow for some
light to moderate showers to push into northern Kentucky and
southern Indiana after midnight. We will see some weak elevated
instability develop in the early morning, which could bring some
rumbles of thunder before sunrise. Otherwise, broken to overcast
clouds will move into the region and WAA will help to keep
temperatures above freezing tonight. Low temperatures are expected
to be in the mid-upper 30s over the Bluegrass and upper 30s to low
40s over the rest of the region.

On Tuesday, the shortwave trough will swing through the Ohio Valley.
In the upper levels, the Lower Ohio Valley will be located beneath
the left exit region. A 40-45kt LLJ will also move over the region.
These features will work together to provide plenty of lift to the
region. Due to the location of the surface low, the lower Ohio
Valley, is expected to be within the warm sector of the system,
where WAA will increase PWATs to near the 90th percentile for this
time of year. Forecast soundings show about 65kts of 0-6km shear and
35kts of 0-3km shear, so there is plenty of shear to support
organization. The only factor that is lacking is the instability.
Looks like we will have about 500 J/kg of MUCAPE and could see some
weak SBCAPE over the southwestern portion of the region. Given these
parameters and features, we will see scattered storms and some may
become strong to severe. Main threats would be hail and a brief spin-
up tornado. These storms are most expected along the cold front late
Tuesday afternoon through the evening. Expecting storms to push east
of the region by about midnight.

Tuesday night into Wednesday morning, clouds look to stay around as
the lower level trough does not move out of the region and the front
stalls in the lower Ohio Valley. Wednesday morning, we will likely
see fog and low stratus over most of the region.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 305 PM EST Mon Nov 17 2025

Wednesday - Wednesday Night...

Broad upper ridging will move east over the region on Wednesday.
However, the stalled front will remain over the region, keeping
clouds and moisture. Weak WAA will help to increase temperatures
into the upper 60s and low 70s over southern Kentucky. Where north
of the stalled boundary will see highs in the low to mid 60s.


Thursday - Sunday...

On Thursday, flow aloft will weaken and become more zonal. Vorticity
shedding from troughing over the desert SW will stream over the
region, bringing another round of showers. The troughing over the
desert SW will then break off and move east into the Ohio Valley by
late Friday into Saturday morning. Continuous moisture transport and
vorticity lobes will keep rain chances in the region through Friday.

By Friday and early Saturday, the trough will develop a low pressure
system that will track into the Ohio Valley. This will allow the
stalled front to lift as a warm front, before the cold front of the
system pushes through. This will bring another chance for storms.

Behind this front, high pressure builds into region bringing drier
conditions for the weekend and into early next week.

&&

.AVIATION /06Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 1256 AM EST Tue Nov 18 2025

A low pressure system is expected to pass from NW to SE across the
region during the current forecast period, bringing likely impacts
to flight categories via reduced CIGs and VIS, especially across
HNB, SDF, and LEX later this morning and into the afternoon. The
likelihood of MVFR or lower CIGs will increase from NW to SE during
the afternoon and evening hours, with MVFR/IFR flight categories
likely by the end of the current forecast period. Scattered to
occasionally numerous showers with embedded thunderstorms are
expected later today, with the main line of thunderstorms expected
to drop through the region with a cold front between 23-06Z tonight
into Wednesday morning.

Winds will be gusty out of the south at BWG today, with the northern
TAF sites expected to be less gusty to the north of a warm front.
There could be some marginal LLWS conditions at SDF/LEX/RGA/HNB
later today due to this front, but with everything else going on,
decided to leave this out of the TAF.

&&

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

&&

$$

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