000
FXUS63 KLMK 280508
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
108 AM EDT Sun Apr 28 2024

...Updated Aviation Discussion...

.KEY MESSAGES...

*   Warm and breezy weather continues, with gusts exceeding 25 mph
    out of the southwest at times on Sunday.

*   Rain chances return Monday into Tuesday. Additional rain chances
    are possible from midweek and beyond, but confidence in the
    timing details remains low.

&&

.UPDATE...
Issued at 911 PM EDT Sat Apr 27 2024

Across the region this evening, warm temperatures and quiet weather
is present across the Ohio and Tennessee valleys. Latest nighttime
microphysics satellite imagery shows mainly high clouds across
central KY and southern IN, with lower cloud layers present
immediately north of the region across central IN. Winds have calmed
considerably in the last 1-2 hours as a typical nocturnal inversion
has set up within the PBL. A few light rain showers have developed
just north of our southern IN counties over the past hour where
there is slightly better low-level moisture. While there is a 5-10%
chance of a sprinkle through midnight north of I-64, would expect
most if not all to remain dry tonight. The main uncertainty in the
forecast overnight is wind speeds as a 50 kt LLJ is expected to
develop from the Mississippi Valley, extending NE into the Wabash
Valley. At this time, given recent obs and trends, expect the low-
level inversion to hold through around sunrise tomorrow, keeping
winds relatively light overnight. Lows should be mild, ranging from
the low-to-mid 60s across the area.

Only minor adjustments were made to the forecast at this time,
mainly dealing with winds overnight. Updated products will be
transmitted shortly.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 250 PM EDT Sat Apr 27 2024

Strong ridging over the eastern CONUS will continue to hold steady
through tommorow. Two low pressure systems located over the upper
Midwest and central Plains will ride along the ridging into southern
Canada. As the first low pressure moves off into Canada, skies will
begin to thin out over the Ohio Valley. Tight pressure gradients
will keep winds up around 10-15mph in the overnight hours. Low
temperatures are expected to be in the low-mid 60s.

On Sunday, skies will remain few to scattered with the ridge axis
over the Appalachians. Tight pressure gradients will continue to
allow breezy conditions on the order of 10-15mph. A 40-45kt LLJ will
meander over the western half of the region in the morning. In the
afternoon, atmospheric mixing up to ~800mb will allow momentum from
this LLJ to mix down to the surface, resulting in wind gusts up to
25mph and some marginal dry air mix down. High temperatures are
expected to be in the low-mid 80s.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 250 PM EDT Sat Apr 27 2024

Unsettled and occasionally wet weather looks likely through much of
next week. The first potential wave of rain and perhaps a few storms
will come Monday as a slow moving, weakening frontal boundary
approaches from the west. Guidance over the last few days has slowed
the progression of this boundary to where some portions of the
region (east of I-65) may end up staying dry the majority of the
daylight hours Monday. This activity will shift eastward Monday
night into Tuesday, with rain likely lingering during the day
Tuesday for portions of the region.

We should see a brief spell of dry weather before additional rounds
of showers and some storms impact us from midweek and beyond. Models
prog a slow moving frontal boundary to be draped from the Great
Lakes region into the central Plains with various
waves/perturbations riding along or near this boundary through this
timeframe. We could initially see some glancing blows from the
activity that develops west of the region, though forecast soundings
show weak low/mid level capping that would not be favorable for
convective development. The better chances for widespread
precipitation in our neck of the woods likely won`t come until the
end of the week when the front finally advances eastward toward us.
Confidence in the timing details remain low, though, as run to run
consistency amongst guidance and ensembles have been poor over the
last few days, and the general trend has been to slow down the
progression of the western/central CONUS trough to the east.

&&

.AVIATION /06Z TAFS THROUGH 12Z MONDAY/...
Issued at 108 AM EDT Sun Apr 28 2024

VFR conditions are expected for the upcoming TAF period.  For the
overnight period, only aviation issue will be LLWS at the terminals
as nocturnal LLJ of 39-44kt will be present overhead.  Winds at the
surface will remain breezy overnight with winds out of the south to
southeast.  For the daytime hours, we`ll see stronger winds mix down
from aloft with speeds of 10-15kts and occasional gusts of 20-25kts
through about 28/22-23Z.

&&

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

&&

$$

UPDATE...CSG
SHORT TERM...SRM
LONG TERM...DM
AVIATION...MJ