276
FXUS63 KLMK 121118
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
718 AM EDT Thu Mar 12 2026

...Updated Aviation Discussion...

.KEY MESSAGES...

* Cooler and dry weather expected today through Saturday. Strong,
  potentially advisory-level gradient winds are expected on Friday.

* A strong cold front is expected to move across the region Sunday
  night into Monday morning. Strong gradient winds are expected,
  with a chance for strong to severe storms along the front.

* Much colder conditions expected for early next week.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 346 AM EDT Thu Mar 12 2026

This morning, the cold front which crossed our area yesterday
afternoon and evening has crossed the Appalachians, with post-
frontal stratus clouds and strong cold air advection continuing
across the Ohio Valley. The last of the rain showers are now pushing
into eastern KY as drier air surges in from the northwest.
Temperatures are currently in the upper 30s and low 40s across the
area, with most locations expected to fall into the 30s for lows
this morning.

Over the next 3-6 hours, the back edge of the low stratus should
begin to clear from NW to SE, with sunny skies returning for all by
midday today. 1032 mb sfc high over the southern Plains this morning
should elongate into a high pressure ridge which extends into the
Ohio Valley by this afternoon. This should promote pleasant, albeit
cooler conditions today, with highs only expected to reach the upper
40s and low-to-mid 50s this afternoon. Deep mixing today should
allow for ample mid-level dry air to reach the surface, and would
expect minimum RH values in the 20s and 30s across the area this
afternoon. Fortunately, with recent rainfall and relatively light
winds, fire weather concerns are expected to be minimal.

This evening into tonight, a compact upper shortwave is expected to
eject across the northern Plains and into the upper Great Lakes,
with an associated sfc low rapidly deepening ahead of the upper
wave. This should result in height/pressure falls to our northwest,
with winds picking up out of the south, especially after midnight.
These increasing winds combined with increasing mid- and upper-level
clouds should keep temperatures from cooling much after midnight,
with lows favored to range from the mid 30s to the low 40s tonight.

Friday will be a milder and windy day across the area as the deep
sfc low moves across Michigan and into Ontario. Ensemble mean progs
feature a minimum pressure below 990 mb, which will lead to a strong
pressure gradient over the Ohio Valley. Given over 60 kt of SW flow
at 850 mb, it is fairly likely that once daytime BL mixing begins,
we`ll get some advisory-level wind gusts across northern KY and
southern IN. NBM exceedance probabilities of greater than 40 mph
wind gusts are greater than 40% along and north of a line roughly
from Tell City to Liberty, with probabilities at the typically windy
locations ranging from 70-90%.

Low-level moisture return is expected to be lacking with Friday`s
system, with little more than extra mid- and high-level clouds
expected. In the past, these setups can typically overperform on
temperatures, so have nudged highs up into the low-to-mid 60s across
the area. By the evening hours, the sfc cold front should push
through the area, bringing modest cold advection into the area. With
winds expected to relax Friday evening into Friday night,
temperatures should fall into the 30s and low 40s Saturday morning.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 346 AM EDT Thu Mar 12 2026

Saturday - Monday...

The cold front which will move through the area later in the day on
Friday should fizzle out over TN Saturday morning before beginning
to lift back to the north during the day on Saturday. With the front
bisecting the area on Saturday, there should be a relatively strong
north-south gradient in temperatures. Current consensus high
temperatures range from near 60 in southern IN to the low 70s along
the KY/TN border. Otherwise, Saturday should be a quiet weather day
with light SE winds and scattered mid- and high clouds.

There have been no major changes in medium-range guidance with the
11/12Z and the 12/00Z runs for the late weekend system, with a
highly-amplified upper trough and strong cold front still progged to
blast through the region Sunday night into Monday morning. As the
system develops over the northern Plains Saturday night, upper-level
height rises over the Ohio Valley should assist the sfc warm front
through the region, with winds becoming southerly across the region
by Sunday morning. Temperatures will be milder Saturday night and
especially on Sunday, with highs likely to surge into the 70s across
the area Sunday afternoon. Given the rapidly deepening sfc low to
our NW, advisory-level gradient winds will certainly be possible
Sunday into Sunday night, with current NBM probabilities of
exceeding 40 mph wind gusts ranging from 30-80% across the area.

As the trailing cold front moves closer to the region Sunday
afternoon and evening, return flow will allow dewpoints to rise into
the 50s across the area, which should at least be sufficient for non-
zero instability as the front moves through Sunday night. While
instability still appears to be limited, the wind field and forcing
for ascent will be extremely potent with this system as the upper
shortwave takes on a neutral- to slightly negative tilt over the
Ohio Valley. While confidence in specifics is still relatively low,
signals for severe convection remain for Sunday night, with CSU and
NCAR AI/ML probabilities gradually increasing. At the very least,
the wind field would support strong wind gusts in rain showers, but
we`ll continue to monitor trends over the next few days in case the
threat increases.

The cold advection behind the front Monday morning should be
extremely strong, with temperatures likely falling over 30 degrees
within the first 3-6 hours of cold FROPA. Depending on how much
moisture lingers behind the front, precipitation could change to
snow on Monday, though this is still fairly uncertain at this point.
What is much more certain is that Monday should be a cold and windy
day, with highs some 40 degrees colder than on Sunday, likely
remaining in the 30s.

Monday Night - Middle of Next Week...

Some of the coldest air since January should settle into the region
Monday night, with lows Tuesday morning likely falling into the
teens to around 20. Even though NW winds will be gradually easing,
wind chills may fall into the single digits Monday night, especially
along and north of I-64. Upper troughing will begin to lift to the
northeast on Tuesday, with a NW flow pattern setting up for the
middle of next week. Within this pattern, we`ll have to watch for a
clipper system which could bring light wintry precipitation Tuesday
night into Wednesday; however, the broader pattern signals mainly
dry weather for much of next week. Temperatures should gradually
warm as we get later into next week as upper ridging across the
western CONUS spreads to the east.

&&

.AVIATION /12Z TAFS THROUGH 18Z FRIDAY/...
Issued at 717 AM EDT Thu Mar 12 2026

Latest surface analysis shows a 1032mb high pressure centered over
TX and building in over the OH Valley, while the cold front pushes
east toward the coast. Current satellite shows low level clouds
slowly exiting to our SE with observations showing the tail edge of
the MVFR stratus from GLW to RGA. Expecting VFR conditions for all
by the start of this TAF cycle. Winds out of the NW will continue to
gust in the 15-20kt range throughout the day. We`ll see a brief lull
in winds this evening as they back to SW, but by early Friday
morning winds will pick up again as the pressure gradient tightens
in response to a low pressure system moving over the Great Lakes.
This will also result in a period of LLWS conditions Friday morning.

&&

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

&&

$$

SHORT TERM...CSG
LONG TERM...CSG
AVIATION...CG