313
FXUS61 KILN 230121
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
921 PM EDT Wed May 22 2024

.SYNOPSIS...
Episodic showers and thunderstorms are expected through the end
of the work week and weekend. Temperatures are expected to trend
above normal through the weekend before a stronger system
impacts the Ohio Valley Sunday into Monday, which will reduce
temperatures to near normal at the beginning of the next work
week.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Evening update...

After a period of brief but rapid intensification, much of the
thunderstorm activity has weakened across the area. The 00Z ILN
RAOB provides a fairly confidence explanation as to why. 0-3 km
shear of 8 knots simply did not allow for the updrafts to
organize after the initial development. Outflow boundaries were
observed moving west and north away from the storm, indicating a
more "pulse-like" thunderstorm mode. The deeper layer shear
briefly allowed storms to organize, producing isolated severe
criteria hail, however, this was short lived even though there
remained plentiful CAPE.

Throughout the rest of the evening, maintained a slight chance
for thunderstorms along the boundary for the next few hours
before limiting it to showers overnight. Added a mention for
patchy fog along and south of the front with clearing of mid-
level clouds and low-level moisture lingering around the front.


&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
A slight cooldown is forecast on Thursday, but temperatures
still trend slightly above seasonal normals. Chances for showers
and thunderstorms will be lower on Thursday, but still linger
given the stalled, weak frontal boundary laying across our CWA.
Locations north of I-70 have the best chance to remain dry all
day, and will also experience slightly lower temps and
dewpoints. Elsewhere, isolated to scattered storm develop still
possible throughout the day, particularly in the afternoon and
evening when we are near peak diurnal heating.

Boundary continues to lift north as a warm front Thursday night.
However, shower/storm coverage will become less extensive
Thursday night.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
In westerly flow aloft, a weak mid level short wave will progress
east across the Ohio Valley later Friday afternoon into Friday
night. Some weak destabilization through the afternoon on Friday
will lead to a chance of showers and thunderstorms, with a better
chance overspreading the area heading into Friday evening as the
short wave moves in. Pcpn chances will then diminish heading into
Saturday as we get on the back side of the short wave.

Another mid level short wave will lift northeast into the Ohio
Valley during the day on Sunday as a stronger secondary short
wave/mid level low pivots northeast out of the mid Mississippi
Valley and into the Great Lakes Sunday night through Monday. This
will allow for an associated surface low to lift northeast from the
central Plains on Sunday into the central Great Lakes through the
day on Monday. Increasing moisture/forcing ahead of this system will
lead to developing showers and thunderstorms Sunday afternoon into
Sunday night and continuing into the day on Monday. Given the
strengthening wind fields and track of the surface low, some severe
storms will be possible, especially later Sunday afternoon into
Sunday night.

An upper level trough will eventually settle in across the Great
Lakes and Ohio Valley region through early to mid next week.
Additional embedded mid level short waves rotating through the
trough will keep some lingering chances for showers and
thunderstorms through the remainder of the long term period.

Temperatures will remain above normal through the weekend with
daytime highs mostly in the upper 70s to lower 80s. A more seasonable
airmass will then move into the region through early to mid next
week with daytime highs mostly in the lower to mid 70s.

&&

.AVIATION /01Z THURSDAY THROUGH MONDAY/...
A line of storms has formed from west-central Ohio into
southeast Indiana. As these continue eastward, there is
potential for this line to impact all TAF sites. Will adjust
timing with amendments over the next couple of hours. For now,
have onset of thunderstorms at the beginning of the TAF with
CVG/LUK/ILN at 1Z. Expect updates to CMH/LCK as the line moves
east.

Otherwise, the rest of the forecast remains on track as the
boundary slides through into the overnight. Winds will weaken
and become variable around 5 kts with this washed out boundary.

Maintained mentions of MVFR CIGs developing Thursday morning.
Better chances and coverage expected for KCVG/KLUK and perhaps
KILN. Confidence is lower on northern terminals with cloud
heights potentially remaining SCT or at VFR heights into the
afternoon.

OUTLOOK...Thunderstorms possible at times through Sunday. MVFR
ceilings possible early Thursday.

&&

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

&&

$$
SYNOPSIS...Clark
NEAR TERM...McGinnis
SHORT TERM...Clark
LONG TERM...JGL
AVIATION...McGinnis