.Short Term...(Today through Friday) Issued at 320 AM EDT Thu Jul 29 2021 
Pre-Dawn up through 12z...  The main focus for the next several hours will
be evolution of Wisconsin MCS.  Impressive MCS with QLCS was moving
southeast across southern Wisconsin early this AM with west to east MLCAPE
axis of near 4000 J/kg pooled in front of it. HRRR Reflectivity and radar
trends support this line moving into our extreme northeastern counties
after 1030z this morning. Meanwhile, the rest of central Indiana will see
increase in convective cloud debris. This will likely result in a lull in
convection ahead of approaching cold front as convective temperatures are
in the lower 90s. That said, approaching frontal boundary and potential
stalled outflow boundary will likely result in robust late afternoon
convection starting up along and ahead of the front. Not exactly sure where
the renewed activity will to start up. Earlier CAM trends had it developing
well south of I-70 but now trends are further north over the I-70 corridor
or even potentially further north. It will again depend in part on
initiation timing which will likely be 19z-22z. Prior to that, expect some
sunshine to break through and allow temperatures to shoot up to the lower
and middle 90s and with dew points in the middle and upper 70s, the Heat
Index may reach 105 to 110 degrees at times over the Wabash Valley, thus
will be issuing a Heat Advisory for this area from 2 PM through 8 PM.  At
any rate, MLCAPE axis to 4000 J/kg pooled along and ahead of the
approaching cold front along with 25 to 35 knot deep shear and deep
moisture will result in explosive afternoon development once the CAP is
broken. Best shear will be over east central sections. This is where an
isolated tornado is most possible, otherwise damaging winds will be the
main threat with hail a smaller threat due to 150K feet freezing levels.
Heavy rain will also be an issue with PWAT`s to 2.3 inches, which is near
the 99th percentile.  The front will move to north central Indiana around
18z, south central Indiana around 00z and central Kentucky by Friday
morning. Thus, expect convection to gradually weaken this evening and end
from north to south.  Saturday will be dry, much cooler and less humid as
surface high pressure moves in behind the cold front. Northeastern sections
may not even see the 80s during the afternoon despite plenty of sunshine. 

NWS IND Office Area Forecast Discussion