522
FXUS63 KLMK 212356
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
656 PM EST Fri Nov 21 2025

...Updated Aviation Discussion...

.KEY MESSAGES...

* Waves of rain showers, with a few embedded storms, are expected
  this evening and into the overnight. Severe weather and flooding
  remain unlikely with this system. Though a few strong storms will
  be possible over far southern Kentucky.

* The late weekend into early next week will see drier weather
  conditions.  Another chance of showers and possible storms will
  arrive late Monday and continue through all of Tuesday.

* Cooler shot of air will arrive for Thanksgiving Day.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 335 PM EST Fri Nov 21 2025

Afternoon satellite imagery shows mostly cloudy skies across the
region, though we have some breaks in the clouds across portions of
southeastern Kentucky.  Afternoon temperatures were in the upper 50s
across southern IN and across a good chunk of north-central and east-
central Kentucky.  Mid-upper 60s were found generally south of the
Cumberland Parkway with readings along the KY/TN border pushing near
70.  Area radars show a batch of more widespread showers lift
northeast across northern Kentucky, with more scattered activity
down across the south.

Low-amplitude shortwave trough axis across the deep south will move
northeast through the TN Valley tonight.  As this occurs, we expect
additional showers and thunderstorms to develop within the warm
conveyor belt from southern MO into TN and KY later this evening and
overnight.  Thunderstorms will likely be limited to areas south of
the WK/BG Parkways.  To the north of the Parkways, soundings show
rather poor lapse rates aloft which will result in updrafts
struggling.  Even down across southern KY, lapse rates are pretty
poor, but low-level hodographs are impressive still for mid-late
November.  A few strong storms can`t be ruled out across far
southern KY, mainly south of the Cumberland Parkway.  The marginal
risk is pretty generous across KY, but we really think the best
threats of any strong storms will be along and south of the I-40
corridor in TN.  Showers and storms will continue into the overnight
hours as the surface low and frontal boundary slide eastward.  Lows
overnight will dip into the upper 40s over southern IN with low-mid
50s over KY.  Behind the front, low-level temp inversion is likely
to set up once again and a combination of low clouds and drizzle
will be leftover behind the departing rainfall.  Will have to watch
obs tonight, but a period of dense fog could develop over southern
IN and into portions of north KY later tonight and early Saturday
morning.

For Saturday, mostly cloudy skies are likely across the region. Area
averaged soundings from the NAM/HRRR show another inversion aloft
developing which will likely trap moisture below it.  So the chances
of breaking out into partly cloudy skies looks much lower than it
did 24 hours ago.  Highs will range from the mid-upper 50s over the
north to the lower 60s across the south.  Drier air looks to finally
work into the region by tomorrow night with lows falling into the
upper 30s/lower 40s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 335 PM EST Fri Nov 21 2025

Sunday through Monday...

Forecast continuity through this time period remains very good.
Upper level ridging will build into the region from the west
resulting in dry conditions on Sunday.  Afternoon highs will range
from the upper 50s to the lower 60s with overnight lows in the mid-
upper 30s.  Highs on Monday should be a little warmer with readings
in the 60-65 degree range.

Monday Night through Friday...

By Monday night, a mid-level wave over the Plains will lift
northeast and open up as it moves into the Great Lakes.  This will
drag a surface boundary through the region on Tuesday.  Ahead of the
front, we expect another round of widespread showers and possible
thunderstorms beginning Monday night and then continuing into the
day on Tuesday.  The risk of severe weather remains quite low here
as model lapse rates and instability are not overly impressive and
the upper level wave is to be weakening as it moves into the Great
Lakes.  Nonetheless, some moderate to heavy rainfall will be
possible here with another 1-1.25 inches of rain.  Much of the rain
looks to push east of the region on Tuesday, but the upper trough
axis will lag behind.  So cloudy conditions are likely to hang
around Tuesday and into Wednesday as well.  Highs Tuesday before the
frontal passage will warm into the low-mid 60s, but look for highs
in the upper 40s/lower 50s for Wednesday.

Clearing skies are expected by late Wednesday and a colder influx of
air will arrive around that time.  Lows Wednesday night will dip
into the upper 20s, though protected valleys could hit the middle
20s. Cold cyclonic flow will remain in place for Thanksgiving day
with high pressure moving through the region.  Highs will likely
feature a gradient across the region.  Readings should top out in
the lower 40s across southern IN and much of north central/east-
central KY.  Mid-upper 40s will be found south of the Parkways, with
maybe some 50s along the KY/TN border.  Lows Thursday night will be
cold with upper 20s expected.

Friday will have to be monitored as a weak perturbation aloft may
sneak into the northern portions of the region.  This may bring some
light snows well to our north with some light rain showers over
southern IN/KY, with perhaps some lingering flurries Friday night.

Extended Forecast Discussion...

Moving into the extended period, earlier thinking on cold weather
arriving sometime during the Thanksgiving Holiday period into late
December is not likely to occur.  Looking at the teleconnection
pattern shows why.  The expected pattern will be in a +NAO/neutral
AO/-EPO/-PNA configuration.  The original idea for late November
cold was based on the NAO to be much more negative yielding
sufficient blocking to get colder air into the US.  A second reason
is that the MJO looks to remain in phase 6 for the remainder of
November which overall is a milder pattern.

While we will see a brief cool down near Thanksgiving, the pattern is
expected to revert back to a milder pattern for the Ohio Valley.
Given the MJO phase 6 and forecast teleconnection pattern with a
weaker NAO blocking signal, a series of lake cutter systems with
lows moving from the southern Plains into the Great Lakes will be
seen.  This will bring periods of unsettled weather to the Ohio
Valley with above normal precipitation and risks of thunderstorms
(some strong/severe).  It would appear that we`ll get a broad
baroclinic zone setting up from the Plains to the Great Lakes.  On
the north side, widespread snows will help build the winter snow
pack from the inter-mountain west into Canada and into the north-
central and northern Plains.  The overall pattern reminds me of
December 2013, at least for the first half of that month.

Models have been insistent on a stronger westerly wind burst over the
far western Pacific which should propel the MJO into Phase 7 as we
head into December.  This would favor much colder conditions on the
north side of the aforementioned baroclinic boundary.  Some south
and eastward spread of the colder airmass across the Plains may
become more evident, especially if stronger blocking can occur up
near Greenland and more significant ridging builds in Alaska.
Assuming the westerly wind burst does its job, the MJO should
continue to propagate into phase 8 which would result in a more
significant cool down as we get further into mid-December.

&&

.AVIATION /00Z TAFS THROUGH 06Z SUNDAY/...
Issued at 656 PM EST Fri Nov 21 2025

The main impacts through the forecast will be LIFR, IFR and a period
of MVFR early in the forecast for a few locations. We will also see
a wind shift from the SW to more north as a system works through
overnight. Low VIS from HNB-SDF-LEX will also develop overnight with
LEX/HNB dropping below 1 mile VIS with CIGs only a couple hundred
feet. Slow improvement during the day with LIFR/IFR flight
categories to start then slowly improving to MVFR later in the day
as we start to slowly clear out from the west to east but it may not
really happen until the end of the period.

&&

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

&&

$$

SHORT TERM...MJ
LONG TERM...MJ
AVIATION...BTN