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561
FXUS63 KLMK 200726
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
326 AM EDT Mon May 20 2024

.KEY MESSAGES...

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*   Dry weather and above normal temperatures today and tomorrow.

*   Unsettled weather late in the week, with highest confidence in
    showers and storms late Wednesday through Saturday.

*   Severe storm potential remains uncertain, with somewhat higher
    confidence in the potential for localized flooding.
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&&

.SHORT TERM /THROUGH TONIGHT/...
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Issued at 325 AM EDT Mon May 20 2024

Synopsis...Mid-level ridge, extending from subtropical high over
Mexico, will consolidate along the Ohio Valley during the next 24
hours as a secondary positive height anomaly core forms over the
Northeast US and Mid Atlantic. At the surface, broad surface high
pressure will transition to the East Coast where some
intensification will occur given rising heights aloft.

Today...As expected, it has been a dry and slightly warmer night
across the forecast area. Surface and satellite observations do not
show any indication of river valley fog at the moment, but it is
still possible especially over the Cumberland and Bluegrass regions.
Otherwise, anticipate a scenic sunrise as high clouds stream in from
the west with a fair-weather cumulus field developing by midmorning
and through the afternoon as solid daytime heating gets underway.
Additionally, highs should warm up to the upper 80s this afternoon
with urban areas probably hitting the 90 degree mark based on Sunday
highs and the fact that weak south winds will slightly enhance WAA.

Tonight...Dry weather will continue tonight but forecast soundings
start to show moistening of the vertical profile as low- to mid-
level winds shift to the southwest in response to approaching trough
and falling mid-level heights. Last but not least, a small and weak
700-mb vorticity wave will move across southern Indiana and north
central KY in the pre-dawn hours with an increase in the cloud
coverage but negligible precipitation chances.
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&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
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Issued at 325 AM EDT Mon May 20 2024

Tuesday through Wednesday Night...

Upper level ridge axis and surface high pressure will hold sway
across the Ohio Valley on Tuesday.  Mostly sunny skies and warm
temperatures are expected.  Afternoon highs in the mid-upper 80s are
expected with overnight lows in the upper 60s to the lower 70s.  By
late Tuesday, the upper level ridge axis will slide off to the east
while a upper trough axis slides in the from the west.  Convection
is likely to develop across the Midwest Tuesday evening and then
work its way eastward into the Ohio Valley by Wednesday morning
while in the process of decaying.  Aforementioned cold frontal
boundary will slowly push into the region during the afternoon and
serve as a focus for renewed convective development.  Model
soundings show decent instability available, but the best synoptic
scale forcing and shear will remain well to our north and to our
west.  While showers and storms look increasingly likely during the
afternoon, a few storms could be strong/severe with damaging winds
and hail being the primary threats, especially in areas north of the
Ohio River. Storms will continue into the evening hours before
weakening late.  Highs Wednesday will be in the mid-upper 80s with
overnight lows in the low-mid 60s.

Thursday through Sunday...

By Thursday, the upper level flow across the CONUS looks to
deamplify slightly with a broad southwest flow regime setting up
from the southern Plains into the northeast.  Frontal boundary from
Wednesday doesn`t look likely it will want to move much as it
becomes parallel to the upper level flow.  Weak perturbations aloft
are expected to move through within the mean flow resulting in
additional waves of showers and thunderstorms in the Thursday
through Saturday period.  The period will not be a total washout,
but episodic bouts of convection are likely to move through the
region during this time period.  Some strong to severe storms will
be possible as instability will be available, but shear is forecast
to remain weak during the period.  Most likely outcome will be
clusters of storms moving through with heavy rainfall and gusty winds
as the main threat.  Repeated bouts of convection may result in some
local hydrologic issues in spots that see repeated storms.  The flow
aloft looks to become slightly more zonal by Sunday which should
allow the front to push on off to the east/southeast resulting in
somewhat drier weather by Sunday.

Highs Thursday and Friday will a bit cooler than what we`ve seen
recently with highs in the upper 70s to the lower 80s.  Overnight
lows will be in the lower-mid 60s.  Temps may warm up slightly for
Sat/Sun with highs returning to the low-mid 80s.
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&&

.AVIATION /06Z TAFS THROUGH 12Z TUESDAY/...
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Issued at 325 AM EDT Mon May 20 2024

Discussion...VFR conditions will continue at all terminals during
this TAF cycle. Surface high pressure over the region will host calm
or light and variable winds throughout sunrise with a weak southerly
component starting around 14Z.
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&&

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

&&

$$

SHORT TERM...ALL
LONG TERM...MJ
AVIATION...ALL