Gatchel, Indiana Weather Forecast Discussion

678
FXUS63 KLMK 231913
AFDLMK
Area Forecast Discussion
National Weather Service Louisville KY
313 PM EDT Tue Sep 23 2025
.KEY MESSAGES...
*  A few strong storms and locally heavy rainfall expected mainly
   this evening through Wednesday.
*  Additional rainfall amounts should range between 1.5 to 3 inches
   for most, although locally higher amounts are possible through
   late Thursday.
*  Dry and increasingly warm this weekend.
&&
.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 313 PM EDT Tue Sep 23 2025
Afternoon satellite imagery shows partly to mostly cloudy skies
across the region.  A rather thick Cu field along with lingering
stratus was noted across the region.  Temperatures ranged from the
upper 70s to the lower 80s.  Convection has been relatively sparse
across the area which has allowed us to recover in spots that saw
heavy rainfall Monday evening.  A large convective complex was noted
across MO and down into northern AR associated with a developing
surface low.  A large high level cloud deck was moving eastward and
will eventually overspread the region this afternoon into this
evening.
As we move into the evening hours, it appears that we may see a NW-
SE oriented line of showers and storms move into the region from the
west.  There remains a bit of spread in the CAMs here, but it
appears that convection may get into our western areas around 22Z
and then into the I-65 corridor around mid-evening (00Z).  This
activity looks to continue to move eastward through the evening.
Some strong storms are possible here, though overall risk of severe
weather remains low due to rather low instability and poor lapse
rates and weak bulk shear.
Overnight, a warm front will develop and push eastward accompanied
by an increasing nocturnal low-level jet axis of 25-30kts.  This
resultant forcing along with an upper level wave approaching should
result in an uptick of convection across the region.  Some strong
storms overnight are possible, mainly across southern KY.  The
threat here would be damaging winds.  However, the more likely
threat will be heavy rainfall that may develop and train across the
region given the low-level jet and expected deep moisture transport.
Model solutions vary with the convective development overnight, so
confidence remains too limited to delineate a specific area for a
Flood Watch.  However, localized flooding in spots will be possible
where training sets up.  Agree with the slight risk of excessive
rainfall from SPC for much of the region here.  Lows tonight will be
in the mid-upper 60s.
Moving into Wednesday, convection may be in progress at the start of
the period.  This activity will likely move off to the east during
the morning hours with another relative lull in precipitation during
the daytime hours.  By the mid-late afternoon, a mid-level jet axis
will overspread the region resulting in decent shear to support
organized convection.  However, widespread cloud cover as indicated
on some of the model soundings suggests that instability may be more
restricted.  In areas that destabilize, another round of showers and
thunderstorms will be possible in the late afternoon and into the
evening hours.  Given the profiles, wind damage would be possible in
the strongest cores.  However, with the surface low going through
southern IN, some backing of the low-level flow may result in some
enhanced SRH would could lead to a low risk tornado threat. In
addition, heavy rainfall and lightning are expected.  Highs on the
day look to top out in the upper 70s to the lower 80s with overnight
lows in the low-mid 60s.
In terms of QPF, another solid 2-3 inches of rainfall looks likely
across the region through Thursday morning.  Some localized 4+"
amounts will be possible in some spots.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 313 PM EDT Tue Sep 23 2025
Thursday through Friday Night...
Upper trough axis will be overhead on Thursday and will slowly
translate eastward.  Thursday will likely be a cloudy day with
scattered showers and perhaps a few storms around.  Severe threat
will be well east of the Ohio Valley here and overall precipitation
intensity looks to be on the lighter side here.  The anticipated
cloud cover will result in highs in the middle 70s with overnight
lows in the mid-upper 50s.
The trough axis will pull off to the east by Friday with an upper
level low developing over the deep South.  This upper low will
become cut off and remain to our south on Friday.  Overall, Friday
continues look drier in each successive model run.  Highs look to
warm into the mid-upper 70s with overnight lows in the low-mid 50s.
Saturday through Monday...
Overall the forecast for the weekend look similar to the previous
forecast.  Dry and increasingly warmer conditions are expected as
ridging builds into the region from the west.  Closed low to our
south will continue to drift over the southeast US.  The Euro
remains insistent on allowing a fetch of moisture to work westward
off the Mid-Atlantic and back into the Ohio Valley.  The Euro may be
overdoing this here as an easterly flow off the Appalachians would
be more of a downsloping type of an event which would be more of a
drier pattern.  Nonetheless, will continue to monitor this, as we
may need to put a shower chance in for Sun/Mon.  Highs during the
period will be seasonal with upper 70s to the lower 80s and
overnight lows in the upper 50s to the lower 60s.
&&
.AVIATION /18Z TAFS THROUGH 00Z THURSDAY/...
Issued at 117 PM EDT Tue Sep 23 2025
Morning low clouds are finally starting to break out.  Look for a
mix of MVFR/VFR cigs at the beginning of the period, improving to
VFR in the next 1-2 hours.  Winds will be out of south/southwest
this afternoon.  Still expecting a lull in the convective activity
this afternoon.  However, signals indicate that scattered convection
may re-enter the area after 24/00Z.  Will continue to advertise with
PROB30s here and attempt to refine this more on the 24/00Z package.
Look for winds tonight to shift to the south and then southeast.
Cigs are likely to come down tonight as well falling into the MVFR
range with possible IFR cigs after 24/08Z through at least the end
of the period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.
&&
$$
SHORT TERM...MJ
LONG TERM....MJ
AVIATION.....MJ

NWS LMK Office Area Forecast Discussion