990
FXUS61 KILN 290603
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
203 AM EDT Sat Jun 29 2024

.SYNOPSIS...
Seasonably warm and humid air builds back in through the start
of the weekend. Isolated showers return tonight, with additional
rounds of showers and thunderstorms possible through Saturday
into early Saturday night. Cold front moves through Saturday
night and leaves a relatively cooler and drier air mass for the
end of the weekend and start of the next work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Extensive cloud cover will be in place overnight. Light shower
activity is starting to move into western portions of the
region. Additional shower activity and some thunderstorm
activity will move in overnight, especially near and north of
Interstate 70. With southerly flow and cloud cover overnight,
expect temperatures to only drop into the lower to middle 70s.

&&

.SHORT TERM /SUNDAY/...
At this juncture, CAMs still remain all over the place on how
to handle PoPs for Saturday. There is growing indication that
our southern counties (closer towards the OH River) struggle to
get any rainfall through Saturday morning. Better chances will
certainly be present for locations along/north of I-70, but
there are some CAMs that still struggle to develop much precip
through Saturday morning in these areas. However, have
reasonable confidence to put high chance or likely PoPs given
that it will be more favorable to at least get some measurable
precip.

Pre frontal showers/storms still expected in some capacity
through Saturday afternoon. Timing/placement will be key for a
number of reasons, including the severe risk potential, along
with determining how high heat indicies will climb for our
southern counties near the OH River. A longer period without
rainfall in our south could lead to some locations near 100
degree heat indicies given that dewpoints are expected to climb
into the lower to middle 70s. While no official heat headlines
are out as of now, have continued with a mention in the HWO.
Just be mindful that a number of locations south of I-70 will
have reasonable chances to reach HI values from the middle 90s
to near 100 given the very humid air mass.

Severe potential will be highest in the afternoon/evening when
instability is maximized, but still not overly confident on this
potential for our counties. CAPE values still may exceed 2000
J/kg, but poor mid level lapse rates will hinder large hail
potential. While straight-line winds would be the primary
threat, a non-zero threat still exists for an isolated tornado.
Shear parameters not very favorable for rotating storms in our
CWA, but rather it looks better for locations ENE of us. The
machine learning products tend to agree with this as well.
Flooding concerns remain unlikely for us as well given the
antecedent dry soils and limited indication of multiple rounds
storms producing heavy rainfall for any particular location.
However, it should be noted that PWATs are 150-175% of normal,
so any thunderstorm will have the potential for producing very
efficient rainfall.

Cold front begins to move through our CWA Saturday night, but
by then, forcing appears more limited and thus coverage in
precip will be more limited too.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
High pressure builds in from the northwest on Sunday and Monday
along with upper level troughing. Cool, dry air arrives with
the high keeping temperatures below average for late June on
northerly winds. Expect fair weather skies to start the week.

The heat and humidity return on Tuesday when upper level
troughing and surface high pressure shift east of the Ohio
Valley. Growing chances for showers and thunderstorms start to
accompany the summer- like conditions by midweek when a weak
front starts approaching from the northwest. Afternoon shower
and thunder chances could persist through the end of the week
since the front appears very slow to progress south.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Through about 15Z Saturday, an embedded mid level disturbance
will ripple across the southern Great Lakes. This feature will
interact with deepening moisture and a low level convergent jet
to result in some showers/embedded thunderstorms, mainly along
and north of I-70 which includes the KDAY/KCMH/KLCK terminals.
Have only included a predominate MVFR visibility at these sites,
but will certainly watch radar trends should amendments be
needed. That is because where thunderstorms occur, MVFR
conditions with local IFR visibilities could be experienced briefly.
Winds will increase from the south to 10 to 15 knots with gusts
developing in the 15 t0 25 knot range.

For later today, the region will be enveloped in a moist
airmass well ahead of a cold front pushing southeast into the
western Great Lakes and middle Mississippi River Valley. Various
convective allowing models try to produce scattered to numerous
showers and thunderstorms again this afternoon as another mid
level disturbance moves east across the area. Timing appears to
be in the afternoon with the northern TAF sites perhaps seeing
the better precipitation coverage. Again, thunderstorms will be
capable of producing MVFR conditions along with at least IFR
visibilities. Southwest winds of 10 to 15 knots with gusts in
the 15 to 25 knot range will continue, but should decrease
between 22Z and 00Z.

For tonight, aforementioned cold front will move southeast into
the central Great Lakes and middle Ohio Valley. Will continue
with a chance of showers and thunderstorms, but coverage should
be sporadic in nature. Models indicate that some MVFR ceilings
may develop in the 06Z and 12Z Sunday time range ahead of the
cold front.

OUTLOOK...MVFR ceilings possible Sunday morning. Thunderstorms
possible Wednesday.

&&

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

&&

$$
SYNOPSIS...Clark
NEAR TERM...
SHORT TERM...Clark
LONG TERM...Campbell
AVIATION...Hickman