334
FXUS61 KILN 301027
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
627 AM EDT Tue Jun 30 2026

.WHAT HAS CHANGED...
Heat Advisory has been upgraded to an Extreme Heat Warning area wide.

&&

.KEY MESSAGES...
1) Extreme heat this week. Hot and humid conditions will continue
into the holiday weekend.

2) Showers/storms possible during holiday weekend.

&&

.DISCUSSION...
KEY MESSAGE 1)

Given the expected amplification of the ridge today and dewpoints
remaining in the middle 70s, heat indicies will more than likely meet
or exceed 105 degrees for most locations. Confidence remains fairly
high in heat indicies climbing to around 105 degrees or so given the
lack of any convective potential with the strong capping inversion in
place. Thus, have upgraded the Heat Advisory to an Extreme Heat
Warning for our entire CWA. This headline will continue through
Thursday given the persistent signal in models that the ridge remains
intact. For Friday and beyond, signal for extreme heat becomes more
murky given the dampening, which could result in more clouds and
precipitation.


KEY MESSAGE 2)

Global models/ensembles have been fairly consistent in showing H5
heights dampening on Friday. As this ridge becomes more suppressed,
multiple shortwaves ripple through the Upper Midwest region. The
closer proximity of this upper level energy will lead to increased
shower/thunderstorm activity across the Ohio Valley.

A little more uncertainty with pcpn coverage on Friday, but ensemble
guidance does have a stronger signal for showers/storms on Saturday.
Given the very unstable air mass, convective activity will likely be
higher for any shower development. Still early to assess the details,
but want to continue to mention this potential given the increased
outdoor activity during the holiday weekend.

&&

.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
A mix of VFR low and high level clouds move across the area today.
Surface winds will increase closer to 10 kts out of the SW during the
daytime hours before subsiding again this evening.

River valley fog expected to develop yet again tonight, with KLUK
having best chance for vsby reductions.

OUTLOOK...Thunderstorms are possible on Friday and Saturday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...Extreme Heat Warning until 8 PM EDT Thursday for OHZ026-034-035-
     042>044-051>053-060>062-070>072-077>081.
     Extreme Heat Warning from noon today to 8 PM EDT Thursday for
     OHZ045-046-054>056-063>065-073-074-082-088.
KY...Extreme Heat Warning until 8 PM EDT Thursday for KYZ089>099.
     Extreme Heat Warning from noon today to 8 PM EDT Thursday for
     KYZ100.
IN...Extreme Heat Warning until 8 PM EDT Thursday for INZ050-058-059-066-
     073>075-080.

&&

$$

DISCUSSION...Clark
AVIATION...Clark