915
FXUS63 KLMK 222331
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
631 PM EST Fri Nov 22 2024

...Updated Aviation Discussion...

.KEY MESSAGES...

*  Isolated rain showers and patchy drizzle will be possible across
   the Bluegrass region this afternoon and evening.

*  After a cloudy and cool start tomorrow, a gradual clearing and
   warming trend is expected over the weekend.

*  Increasing rain chances Monday and again for the middle of next
   week.

&&

.UPDATE...
Issued at 630 PM EST Fri Nov 22 2024

Added patchy drizzle to a much larger area of the CWA as KLVX and
TSDF radars both show consistent returns over much of the area. This
combined with a few obs showing some -dz or -ra mention at times is
enough to include mention. Have it lingering through the evening
hours, but still expecting an eastward taper into the overnight.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 323 PM EST Fri Nov 22 2024

Across the region this afternoon, a large area of stratus continues
to sprawl overhead as low-level moisture remains trapped below a
subsidence inversion. A fairly strong pressure gradient remains in
place over the region between 990 mb sfc low over the Poconos and
1025 mb sfc high extending across the eastern Great Plains, allowing
for continued gusty west-northwest winds. Temperatures over central
KY and southern IN are mainly in the 40s this afternoon, and most
locations should remain fairly steady through the rest of the
afternoon as clouds continue to fill in.

Later this afternoon, an area of deeper moisture moving in from
eastern IN and western OH should saturate to sufficient depth for a
few light rain showers or areas of patchy drizzle to form across the
Bluegrass region. Other than temporarily reduced visibilities and
light precipitation amounts, this shouldn`t be too impactful given
temperatures are well above freezing and should subside by midnight.

Tonight, low clouds should linger over the region with weak cold
advection continuing around 925 mb and the mid-level subsidence
inversion strengthening. These clouds should keep temperatures
fairly steady overnight, with lows Saturday morning only expected to
fall into the upper 30s to around 40 degrees. Winds should gradually
ease during the late evening hours, though a persistent 5-10 mph
west wind should continue overnight.

Tomorrow should be a transition day as the upper low exits into the
Canadian Maritimes and ridging moves into the Ohio and Tennessee
Valleys. Low-level cold advection should slowly end during the day
tomorrow, which should begin the process of clearing pesky low
clouds. However, this will be a gradual process from southwest to
northeast, with clearing expected earlier in the day along the TN
border and clouds holding on longer across southern IN and north
central KY. It is even possible that areas along and north of I-64
do not clear out until Saturday night. Temperatures will be highly
dependent on the amount of low cloud clearing, and there is a fair
amount of spread in short-range progs. For this forecast, have
tended on the cooler/cloudier side of guidance since low clouds tend
to hang on longer than most model depictions. This gives a range of
highs from the mid 40s over the Bluegrass region to the low 50s
across south central KY. Winds should be westerly tomorrow, with
speeds lighter around 5-10 mph.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Issued at 323 PM EST Fri Nov 22 2024

The medium range forecast starts off cool and dry Saturday night.
Flattening ridging aloft will gradually build eastward toward the
region as sfc high pressure moves across the Southeast. We`ll see
light SW flow, and steady low-level WAA should help promote a
gradual clearing trend. Partly cloudy to mostly clear skies Saturday
night may allow to fog to form as the BL decouples and temps drop.
Lows should reach the low to mid 30s in most areas.

Low-level SW flow increases Sunday as low pressure develops eastward
over OK/KS. Look for warmer and dry conditions, with afternoon highs
in the upper 50s to lower 60s.

Low pressure is forecast to continue lifting NE into the Lower Great
Lakes Sunday night and Monday, with a trailing cold front cutting
southeast through the Mid-MS Valley, Ozarks, and eventually Ohio
Valley. It appears we`ll most likely stay dry into Monday morning,
with deep moisture confined to a zone just along and ahead of the
sfc cold front. Stout SW LL flow and dry conditions will result in a
milder night, with Monday morning lows in the mid 40s to lower 50s.

A round of light to moderate showers looks likely Monday afternoon
and evening as the cold front sweeps through the region. High temps
should range through the 60s. Around 0.10-0.25 inches of rain looks
possible through Monday night. Precip shuts off quickly Monday night
as much cooler, drier air pours into the region. Temps will drop
into the 30s by early Tuesday.

Tuesday looks dry and chilly. Upper level flow transitions to a more
zonal pattern as sfc high pressure builds east toward the region.
Afternoon highs will likely be in the 40s. Sfc high pressure builds
east across KY Tue night, which should allow temps to drop into the
mid 20s to lower 30s. There is some uncertainty on upper level sky
cover trends, especially heading into Wednesday, as another low
pressure system gets organized over the southern Plains. This system
could bring another round of precipitation Wednesday into Thursday,
but confidence on the details/evolution remains very low at this
time.

&&

.AVIATION /00Z TAFS THROUGH 06Z SUNDAY/...
Issued at 630 PM EST Fri Nov 22 2024

Stratus is currently plaguing the TAF sites, and will continue to do
so for much of this TAF cycle. Also seeing some patches of drizzle,
but don`t think these will be too impactful. There is some optimism
for improvement by tomorrow afternoon, but we will likely see
prolonged MVFR ceilings until then. It is looking like ceilings will
mostly stay between the 1 and 2K foot threshold this evening and
through the overnight, with LEX having the best shot at some brief
IFR. Otherwise, look for steady W to WNW winds gradually slackening
overnight, and then backing to a light SW component tomorrow
afternoon. This will help to finally eradicate the MVFR ceilings, so
expect some improvement through the PM hours.

&&

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

&&

$$

UPDATE...BJS
SHORT TERM...CSG
LONG TERM...EBW
AVIATION...BJS