516
FXUS61 KILN 072329
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
729 PM EDT Mon Jul 7 2025

.SYNOPSIS...
A cold front will move across the area this evening, with showers and
thunderstorms expected. While slightly less humid conditions are
expected on Tuesday, heat and humidity will remain in place through
the week, with occasional chances for storms.

&&

.NEAR TERM /THROUGH TUESDAY/...
Early this afternoon, the cumulus field over the ILN CWA has become
robust, as uncapped instability is being realized. Some showers and
storms have already developed, and development will continue to
increase through peak diurnal timing later this afternoon. A frontal
boundary is currently in place from south of Indianapolis IN to near
Cleveland OH. Conditions are more stable along and north of this
front, but ahead of the front, temperatures on the way to the mid 80s
to near 90 (in the far southeast ILN CWA).

The KILN 12Z sounding recorded a precipitable water value of 1.65
inches. The greater plume of moisture is now advecting into the area,
ahead of the cold front. This will provide a very moist environment
for storms to develop within. SBCAPE values of 1500-2000 J/kg can be
expected, and the overall forecast thinking for hazards today has
not changed -- a risk of isolated flooding due to heavy rainfall
rates (especially with training or slow-moving cells) along with a
low-end threat for damaging wind gusts from wet microbursts. he 1630Z
SPC D1 outlook continues to include much of the forecast area in a
Marginal Risk for severe weather.

Convection should be dissipating after 02Z, at which point some fog
or stratus may develop. Have not included fog in the public forecast,
as confidence is not high that it will be particularly dense, but
this scenario is not out of the question.

&&

.SHORT TERM /TUESDAY NIGHT/...
By Tuesday morning, the cold front is forecast to be most of the way
through the ILN forecast area, but it is expected to weaken and
mostly wash out by the time peak heating is underway. Regardless of
how this plays out, there is strong agreement that the air mass will
be a little less moist and a little less unstable. With no clear
signs of forcing, any convective activity should be much more
isolated. For the ILN CWA, any storm chances on Tuesday will be
favored in the southeastern CWA. Still, could probably not entirely
discount the chance of a shower just about anywhere -- though the
chances are very low at any given location. Anything that develops
will likely dissipate by evening, leading to dry conditions overnight
into Wednesday morning.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
An active long term pattern will be in place with daily thunderstorm
chances.  Daily thunderstorm chances will keep temperatures generally
in the 80s, although a few isolated 90s cannot be ruled out.  Lows
will generally be in the middle 60s to lower 70s.  Although heavy
rain with downpours and isolated damaging winds cannot be ruled out
on any particular day with this pattern, the best chance for this
occurring will be on Wednesday.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
While the bulk of the SHRA/TSRA activity has cleared the local
terminals, the front itself still remains just N of every local site
except KDAY. Therefore, a few spotty SHRA will be possible through
the first part of the TAF period for srn sites. Have added a PROB30
to account for this potential, although the coverage should become
increasingly isolated toward/beyond 06z. However, there is a signal
for a few spotty SHRA to linger through the night (perhaps migrating
more E of KILN and S of KCMH/KLCK past 09z), so suppose that it
cannot be ruled out at these sites through daybreak.

The main item of interest through the TAF period is going to be the
development and expansion of some MVFR/IFR CIGs and VSBYs, which
will be most widespread/persistent for nrn sites. This will
especially be the case beyond 06z, with some low stratus and BR/FG
favored to develop. Still some uncertainties regarding how low the
VSBYs will go with the expanding stratus deck, but do think that
MVFR/IFR VSBYs will develop in a fairly widespread fashion,
particularly between 09z-12z. Some LIFR conditions could develop
briefly. Conditions will improve rapidly after 12z, with the stratus
expected to lift/SCT through the morning, with a FEW/SCT VFR Cu for
the afternoon.

A very spotty SHRA cannot be ruled out during the afternoon, but the
lack of coverage precluded inclusion of even a PROB30 at this
juncture. Light/VRB/calm winds through daybreak will go more out of
the WNW at 6-8kts during the daytime.

OUTLOOK...Thunderstorms are possible each day from Thursday through
Saturday, mainly in the afternoon and evening.

&&

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

&&

$$

SYNOPSIS...Hatzos
NEAR TERM...Hatzos
SHORT TERM...Hatzos
LONG TERM...
AVIATION...KC