684
FXUS63 KLMK 080159
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
859 PM EST Fri Feb 7 2025

.KEY MESSAGES...

*  Widespread rain returns late tonight and continues into Saturday.
   A few rumbles of thunder are possible on Saturday.

*  Multiple waves of precipitation are expected next week. There is
   low confidence in precipitation type, though wintry precipitation
   is possible Tuesday and Thursday. Precipitation amounts will lead
   to an enhanced potential for flooding mid-to-late next week.

&&

.UPDATE...
Issued at 859 PM EST Fri Feb 7 2025

Satellite and observations reveal mostly cloudy skies across the
region this evening.  Temperatures were in the lower 40s over much
of northern and north-central Kentucky.  Temps were slightly warmer
down across southern KY (south of the Cumberland Parkway) where
readings were in the upper 40s.

Radar shows returns moving from west to east across the region. Much
of this precipitation was a mix of rain and sleet due to the
antecedent dry air in place across the region.  The sleet will not
be impactful due to air temperatures remaining well above freezing.
Overnight, warm air advection will take shape as a warm frontal
boundary lifts northward.  Isentropic lift mainly along the 295K
surface is expected to increase and that should allow precipitation
to become a bit more widespread through the overnight.  We may
continue to see a rain/sleet mix over our far northeast CWA into the
overnight as temps will likely be in the mid 30s toward sunrise in
that area. Elsewhere temps will be in the upper 30s/lower 40s across
KY.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 315 PM EST Fri Feb 7 2025

Things are quiet across the CWA at this hour, with a light northerly
wind and some mid level clouds beginning to build into our region.
Some blips currently on the radar, but these are just mid level
returns for now. As we move into the evening, cloud bases lower to
the point where some sprinkles may occur on the leading edge of the
main precipitation shield. Temps are currently ranging in the 40s
and probably won`t go a whole lot higher today, given the increasing
cloud cover.

Deteriorating conditions are expected through tonight as a surface
low over the central High Plains begins to slowly eject out. Stalled
frontal boundary to our south will begin to lift northward tonight
as the low level jet responds over our area. Classic isentropic lift
presentation on the 295K pressure surface suggests the low levels
will gradually saturate with light rain commencing from SW to NE
after sunset, then categorical chances really ramp up after
Midnight. Will have to watch our NE and make sure they aren`t below
freezing with the onset of light precipitation or drizzle, but do
think we trend milder pretty quickly and any freezing precipitation
will be mitigated or very short-lived at best.

A steadily strengthening surface low moves through the Ohio River
Valley tomorrow, with the warm front continuing to lift northward
over our area ahead of the low. This will establish a warm sector at
least across part of our CWA, with a large gradient from S to N.
Expect highs in the low 70s across southern KY, and only in the mid
50s across southern IN. Tough temperature forecast with plenty of
spread among ensemble members, but worth noting that we didn`t lean
toward the highest of guidance given the amount of precipitation and
cloud cover. Will note that our southern CWA will likely see some
reprieve from light showers through the late morning and early
afternoon as the warm sector briefly gets established, however any
break will be short-lived as the cold frontal precipitation develops
through later in the afternoon and evening.

Where we do get the warm sector, expect winds will be fairly gusty
given deeper mixing into the decently strong LLJ aloft. Will
advertise gusts in the 20-30 mph range, with the idea that we won`t
fully realize the wind potential due to low level lapse rates not
being as steep. If we do get some breaks in the clouds in our south
then the ability for temps to overachieve and deeper mixing for
stronger gusts will be possible.

Still can`t rule out a few rumbles of thunder due to some meager
elevated instability, but overall probs land at less than 15% so
won`t carry in grids. It is nice to see a notable inversion around
700 mb on forecast soundings, and this will be our saving feature
from a severe weather threat. Shear profile is otherwise quite
favorable, so a good thing there.

Overall QPF looks to range in the .5" to .75" range for central KY,
with .25" to .5" north and south of central KY. This won`t help our
ongoing moist conditions, but also not enough to worry about any
real flooding concerns other than delaying some river falls,
perhaps.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Issued at 315 PM EST Fri Feb 7 2025

Rain will begin to diminish from west to east Saturday evening into
Sunday morning as the cold front pushes through the region. Modified
cPa and deep CAA will result in Sunday morning mins in the upper 20s
across southern Indiana gradually increasing to the mid 30s across
southern KY. Expect dry conditions to follow for most of Sunday as
surface ridging builds in from the NW with quasi-zonal flow aloft.
High temperatures on Sunday will be notably cooler with afternoon
max Ts only reaching into the low to mid 40s, which is actually
quite close to climatological normals.

Dry conditions will continue into Monday with morning lows in the
mid to upper 20s across southern Indiana and into the low 30s across
southern KY, as sfc high pressure migrates eastward across the OH
Valley. Look for afternoon highs in the low to mid 40s again for
Monday.

Upper pattern begins to change as a deepening trough moves into the
SW CONUS resulting in SW flow aloft over the eastern half of the
country. This sets up a parade of PVA along the southern stream,
which will bring rain and snow to the region Monday night into
Tuesday. Confidence in the exact track of the southern stream system
remains low due to subtle differences between global models, but
enough ensemble members are continuing to lean towards snow for
portions of our CWA. Model soundings would suggest a mix of rain and
snow for much of the area. Southern Indiana and central KY have the
greatest likelihood of receiving snow amounts of around an inch,
while southern KY will likely experience all rain.

We may experience a brief lull, though drizzle or snow flurries may
continue, through midday Wednesday before another shortwave pushes
through the region bringing another round of mixed precip.
Confidence is even lower with this system in regards to specific
snow amounts and low track, but models do suggest this system being
a bit more robust. Will continue to monitor model trends, so stay
tuned for the latest.

&&

.AVIATION /00Z TAFS THROUGH 06Z SUNDAY/...
Issued at 632 PM EST Fri Feb 7 2025

Period will start off with VFR conditions this evening, but look for
conditions to deteriorate overnight as a warm frontal boundary lifts
northward across the region.  Cigs overnight will lower into the
MVFR range with scattered showers moving across the region.  A low-
level jet around 35-40kts will result in LLWS at the terminals
overnight, just above an expected temperature inversion.  Like the
last forecast, will keep the LLWS at 1500 ft agl.  Warm front will
lift northward through the region Saturday morning resulting in
winds shifting from the SE to the SW and becoming quite gusty in the
afternoon.  Gusts of 18-24kts will be possible.

&&

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

&&

$$

UPDATE...MJ
SHORT TERM...BJS
LONG TERM...CG
AVIATION...MJ