524
FXUS61 KILN 260725
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
325 AM EDT Wed Jun 26 2024

.SYNOPSIS...
Showers and thunderstorms are expected again through today as a
cold front moves through the Ohio Valley. High pressure and a
drier airmass will return for Thursday and Friday. Before warm
and humid air returns again by Saturday, along with the chance
for additional rounds of showers and storms.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Mainly quiet conditions have evolved locally this morning as the
environment remains relatively stable in the wake of Tuesday
afternoon activity. Although a rogue shower or storm cannot be
ruled out through daybreak (especially near/S of the OH Rvr and
into SE IN), most spots should remain dry into the early daytime
hours. Temps will remain generally in the upper 60s and lower
70s through sunrise.

As we progress toward/beyond 14z or so, the MCV currently
churning across srn IL will have migrated into SE IN. On the
leading edge of this feature, a slightly stronger LLJ will
provide the focus for renewed lift amidst a gradually/subtly-
destabilizing LL environment. On the ern flank of the MCV,
additional SHRA/TSRA development is expected in SE IN and the
Tri-State before activity /potentially/ becomes better
organized into a N-S oriented broken cluster into early
afternoon as it generally tracks to the ENE near/S of the I-71
corridor. This broken/semi-linear cluster of storms, assuming it
can develop more established cold pools, may provide a focus
for isolated gusty to damaging winds, especially as it migrates
into parts of central/south-central OH and NE KY into early/mid
afternoon. But that is a big assumption, especially as there
are quite a few limiting factors that could inhibit a more
widespread severe risk -- most notably the relatively meager deep-
layer and SB-instby, owing to /very poor/ midlevel lapse rates,
which should limit sustained robust updraft strength. While
confidence in storm coverage today is high, confidence in severe
potential, or coverage of strong to severe storms, is much
lower owing to an unimpressive thermodynamic setup. Amidst an
amply-saturated environment and the increase in forcing/lift
(due to the MCV in early/mid afternoon followed by the front
itself late afternoon into early evening), there may be several
rounds of storms through the near term period for any one
location. This being said, coverage of storms should taper off
from NW to SE in the several hour period around sunrise as the
front pushes the better LL moisture to the S and drier air
filters in from the N toward midnight and beyond. Do think that
the best, albeit still uncertain, potential for a few strong to
severe storms will be early to mid afternoon near/S of the I-71
corridor with activity associated with the MCV. That is not to
say there won`t be some gusty wind potential with the storms
along the front itself during the evening, but do think the
overall severe threat for today may materialize lower than
originally anticipated.

Highs today will be highly-variable, owing to convective
influences. For some locales, highs will be reached in early
afternoon before the arrival of storms while in others it may be
reached late afternoon in between the storms associated with the
MCV and the activity along the front itself.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Drier air and cooler temps filter in from the N tonight,
allowing for temps to dip into the lower/mid 60s by daybreak
Thursday. Temps will rebound into the lower/mid 80s amidst
plentiful sunshine, light northerly sfc flow, and a few
afternoon-driven Cu. Dewpoints will dip into the upper 50s
for many near/N of the OH Rvr Thursday afternoon.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Overnight lows into Friday might be some of the coolest we`ve seen
all week, falling to the upper 50s with patchy cloud cover. However,
the next disturbance is on the horizon as a shortwave moves through
the larger flow. Friday daytime hours we`ll see an increase in
mid/upper level cloud cover as warm, moist air is pumped back into
the region behind the lifting warm front and highs will reach the
upper 80s again.

The parent shortwave continues to move along the CONUS/Canadian
border and slowly open up into a wave. The associated surface
disturbance, while rather broad, is loosely organized and looks to
pass along the northern Great Lakes Saturday, dragging a cold front
in its wake. Given that the ILN CWA will still be in the open warm
sector during this time, Saturday will likely be quite muggy with
highs in the 90s and dew points in the upper 70s. Additionally,
there is decent consensus that PWATs will be above 2 inches (nearly
three sigmas above normal) and with the chance for showers in the
muggy airmass ahead of the cold front, do have some concerns that any
storms that train may produce localized flooding.

Right now, it looks as though the cold front will be pulled through
the region sometime Saturday into Sunday hours. Bit too early to get
hung up on severe threat, however, should the front move through
while there is still enough daytime instability present (combined
with marginal mid-level forcing) we may end up with a few storms
that are able to produce some stronger winds.

After the front moves through, temperatures on Sunday and Monday
reach upper 70s (north) to mid 80s (south) with a decline in muggy
conditions thanks to some northwesterly flow. The next disturbance
looks to move into the region mid-week as a broad 500H trough digs
into northern CONUS.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
A few rogue SHRA/TSRA will continue to percolate about the Tri-
State area through daybreak, potentially very briefly impacting
KCVG/KLUK. Elsewhere, expect mainly dry conditions to persist
through sunrise before widespread SHRA/TSRA moves in past mid-
morning.

Expect an initial cluster of SHRA/TSRA to develop/move into the
Tri-State after 12z, generally tracking to the ENE through the
morning into early afternoon, potentially impacting each of the
local sites to some degree, especially between about 14z-18z.
This may be followed by a several hour break mid afternoon,
especially for KCVG/KLUK/KILN where it will clear out faster
behind this initial activity. However, additional widespread
SHRA/TSRA will pivot back in from the N between about 22z-01z,
likely impacting each terminal for at least an hour or two with
some reduced VSBYs and TSRA. Did not yet have confidence to add
significantly reduced VSBYs into the fcst for the evening, but
certainly some MVFR/IFR VSBYs are to be expected in the heaviest
activity. Could also see some brief MVFR CIGs as well.

A drying trend should evolve from NW to SE after about 01z,
particularly for the local TAF sites. Light SW winds early in
the period will increase to about 12-15kts, with gusts to around
20kts, during the afternoon before abruptly shifting to out of
the N with the passage of the front during that 22z-01z time
frame. Light northerly winds at 5-7kts are expected for the
final part of the TAF period, with skies trending toward SKC
around/after 06z.

OUTLOOK...Thunderstorms possible Saturday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.

&&

$$
SYNOPSIS...KC
NEAR TERM...KC
SHORT TERM...KC
LONG TERM...CA
AVIATION...KC