143
FXUS63 KLMK 310652
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
252 AM EDT Fri May 31 2024

.KEY MESSAGES...

*   Dry weather and below normal to normal temperatures expected
    through Friday night.

*   Rain and storm chances return for the weekend and continue into
    next week. Temperatures and dewpoints will also be on a steady
    increase into next week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 251 AM EDT Fri May 31 2024

Dry and pleasant weather will continue today as high pressure
shifts slightly from the Great Lakes to the Appalachians. However,
expect a bit more cloud cover than yesterday, with upper level
cirrus increasing later today from the west that is associated with
a 500mb shortwave. NBM is a bit aggressive with the cloud cover this
morning, so will go against the NBM guidance and keep skycover
mostly clear/sunny to start, but will see the cloud cover increase
later this afternoon and especially this evening and tonight.
Temperatures will reach the upper 70s to around 80.

For tonight, expect mostly cloudy skycover as a mid-level shortwave
ejects out of Arkansas. It`ll be dry for most of the region tonight,
but will introduce a 15-20% PoP after 06z for our counties west of I-
65 as the eastern periphery of the moisture transport axis begins to
work into central Kentucky and southern Indiana after midnight.
Model soundings show lingering dry air in the lowest 1km between 06-
12z Saturday morning, so perhaps some virga in the predawn hours
before we fully saturate the column. Better chances for accumulating
precip arrive in the Long Term period.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 251 AM EDT Fri May 31 2024

After nearly a week of dry weather for most, rain will make a return
to the region on Saturday. Models prog modest isentropic lift along
~305K surfaces ahead of a compact shortwave that will tumble into
the Ohio and Tennessee Valleys on Saturday. Deeper moisture with
Gulf of Mexico origins will be drawn northward ahead of this
shortwave, and the combination of lift/forcing in conjunction with
the deeper moisture will promote rain shower development as early as
Saturday morning. We could see `waves` of rain through the weekend
as the shortwave slowly advances eastward. Model soundings over
southern IN and central KY show very poor low and mid level lapse
rates, indicating that instability will be at a minimum. The lack of
instability should keep overall thunderstorm chances low, and any
strong/severe storm chances near 0% despite some marginal deep layer
shear in the environment.

Warmer and more humid conditions return by early next week and will
likely continue through at least midweek as the main jet flow/energy
stay confined to the northern U.S. Subtle shortwaves could tumble
into the region during this timeframe and spark off showers/storms
any time of the day or night, but outside of those waves, most
precipitation chances will be driven by mesoscale features and
likely be highest in the afternoon and early evening hours. A fairly
modest upper level trough (by early June standards) and surface cold
front looks to pass through the region by late Wednesday or Thursday
and should bring a return to cooler temperatures and lower dewpoints
by Friday into next weekend.

&&

.AVIATION /06Z TAFS THROUGH 12Z SATURDAY/...
Issued at 106 AM EDT Fri May 31 2024

High pressure across the region will keep VFR conditions through the
period, with only some upper level clouds to speak of. A fairly dry
column will limit the diurnal cu field today, with this TAF issuance
mainly a wind forecast. As the sfc high migrates slowly east across
the Great Lakes, winds will be around 10 kt from due east for most
of the day. Upper level ceiling will begin to arrive from the west
towards the end of the period ahead of our next sfc low.

&&

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

&&

$$

SHORT TERM...CJP
LONG TERM...DM
AVIATION...CJP