414
FXUS63 KLMK 241104
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
604 AM EST Tue Dec 24 2024

...Updated Aviation Discussion...

.KEY MESSAGES...

* Brief light rain or sprinkles possible this morning. Temperatures
  fairly steady in the 40s today.

* Above normal temperatures Tuesday through the end of the week.
  Multiple disturbances to bring rain chances most days.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 245 AM EST Tue Dec 24 2024

An upper level shortwave trough is dropping southeast over eastern
Canada and the Great Lakes this morning. A very weak sfc boundary
extends southwest through DTW and STL. A 30-35 kt WSW LLJ is in
place over southern IN and north-central KY early this morning,
where scattered light rain and sprinkles are ongoing. The parent
wave will swing east to New England this morning, leaving behind a
diffuse frontal zone. The loss of low to mid-level ascent will
result in diminishing radar returns through the mid to late morning
hours. Relatively dry conditions should then linger through the
afternoon and early evening hours.

Overall, it looks like a rather dreary and damp day. The chance for
measurable precipitation is actually fairly low, with only very
light rain and sprinkles early in the day. Temperatures are in the
low to mid 40s in most places early this morning and should only dip
slightly through daybreak. Expect a small diurnal temperature range
through the next 24 hours with abundant moisture and cloud cover.
Highs today will be in the mid to upper 40s for most. Temperatures
may briefly reach the low 50s in southern KY. Temperatures are
forecast to drop back into the upper 30s to lower 40s early
Christmas morning.

Tonight, the next upper level shortwave trough begins to move east
from the Plains toward the MS Valley. With the moisture already in
place, weak low-level ascent and WAA should be enough to generate
light rain in southern IN and western KY.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 245 AM EST Tue Dec 24 2024

Cloudy and warm for late December with chances for rain on Christmas
Day as stationary frontal boundary remains positioned over the area.
Highs in the lower 50s on Wednesday will be about 7 to 10 degrees
above normal. The frontal boundary will start to move northward as a
warm front Thursday into the coming weekend with high temperatures
reaching well above normal for late December into the upper 50s and
lower 60s (on the order of 14-17 degrees above normal) with more
chances for rain as a cold front approaches from the west
Saturday/Sunday.  At this point, early indications show that a
decrease in temperatures heading into next week is unlikely.

Model atmospheric profiles show a lack of instability and
temperatures above freezing, so not expecting any snowfall or severe
weather potential for the long term forecast through the coming
weekend.  However, GFS model soundings are starting to hint at a
more unstable atmosphere for a storm system heading into the middle
of next week around NYE with CAPE and wind dynamics (0-1 KM and 0-6
KM shear numbers) elevated.  While confidence is low at this point
for any severe weather, we`ll have to keep an eye on this system
evolution in the coming days.

&&

.AVIATION /12Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 603 AM EST Tue Dec 24 2024

Impacts...

* MVFR CIGS developing this morning and lingering until early
  Christmas morning.

HNB is now MVFR, and CIGS will continue to lower to MVFR at SDF, LEX
and RGA this morning. BWG will remain VFR. A very weak front draped
NE to SW through central IN/IL early this morning will wash
southeast over the Ohio Valley today. Spotty light rain and
sprinkles ongoing this morning will largely diminish by 15Z.

MVFR CIGS will persist until late in the TAF period, at least at
HNB/SDF/LEX. Low-level moisture lifts northward early Christmas
morning, resulting in a return to VFR CIGS. SW winds around 5 kt
this morning will become light and variable by this evening. Very
light (easterly) to calm winds expected overnight into Christmas
morning.

&&

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

&&

$$

SHORT TERM...EBW
LONG TERM...MCK
AVIATION...EBW