The National Weather Service has issued a Tornado Watch for much of the tri-state area.

Here are the details from the NWS:

.DAY ONE...This Afternoon and Tonight

Scattered thunderstorms will be possible, mainly very late this
afternoon into tonight, over much of the quad state region.

A few storms may become strong to severe, especially over portions
of southeast Missouri, western Kentucky and the southern tip of
Illinois. While large hail, damaging wind gusts and locally heavy
rainfall will be the primary hazards, a tornado or two cannot be
ruled out.

And here are the lists of counties under the watch:

IN
.    INDIANA COUNTIES INCLUDED ARE

GIBSON               PIKE                POSEY
SPENCER              VANDERBURGH         WARRICK
KY
.    KENTUCKY COUNTIES INCLUDED ARE

BALLARD              CALDWELL            CALLOWAY
CARLISLE             CHRISTIAN           CRITTENDEN
DAVIESS              FULTON              GRAVES
HENDERSON            HICKMAN             HOPKINS
LIVINGSTON           LYON                MARSHALL
MCCRACKEN            MCLEAN              MUHLENBERG
TODD                 TRIGG               UNION
WEBSTER