025
FXUS63 KIND 160652
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
252 AM EDT Wed Sep 16 2026

.KEY MESSAGES...

- Hot temperatures will continue at times into Saturday, especially
  south. Heat indices around 100 again today and Thursday.

- Scattered showers and storms today, but severe storms are not
  expected

- Shower and storm chances persist for much of the time into
  next week, with temperatures turning cooler next week

&&

.DISCUSSION (Today through Tuesday)...
Issued at 252 AM EDT Wed Sep 16 2026

Early This Morning...

Energy riding around an upper high with help from a surface front
has been generating convection from northern Missouri into the
northern forecast area. Looking upstream, there may be a brief lull
as convection remains just west and north of the area, but more will
move in closer to sunrise. Outflow from the convection has reached
the I-70 corridor, and this may spark an isolated shower in that
area. Will continue with mainly chance PoPs from about I-70 north
through 12Z.

Some gusty winds and heavy rain are possible, but odds of severe
remain low given lessening instability.

Today...

Some stronger upper energy looks to bring showers and some storms to
portions of the northern forecast area after 12Z, so will go with
high chance to likely category PoPs there. Will keep chance PoPs
south of this area this morning in case outflow is enough to trigger
more isolated to scattered convection.

There looks to be less upper support this afternoon for convection,
but with various old outflows in the area as well as the surface
front, will go with at least slight chance PoPs most areas this
afternoon. The far southern area may be far enough from outflow and
close enough to the upper high to remain dry. Severe parameters look
low enough that severe storms are not expected, but a gusty storm is
possible. Locally heavy rain will remain a threat with a moist
atmosphere.

Convection/clouds will help keep temperatures cooler across the
northern forecast area, so went middle to upper 80s. The central
forecast area looks more uncertain thanks to the questions about how
much convection will be generated by outflows and the surface front.
Will go lower 90s there. The south should still be able to reach the
middle 90s. Heat indices will reach around 100 again this afternoon
for much of the area.

Tonight and Thursday...

More energy riding around the slowly retreating upper high along
with the old surface front will keep chances for convection around,
mainly across the northern half of the area. Similar to today,
clouds/convection Thursday will keep temperatures cooler north with
hot conditions persisting south. Heat indices will remain around 100
south during Thursday afternoon.

Friday and beyond...

The upper high will continue to gradually retreat southwest. The
surface front will sink far enough south initially to keep PoPs low
on Friday, but it will return north again on Saturday as an upper
wave interacts with the front. This will bring more rain chances,
mainly north.

After a brief reprieve from heat for many areas Friday, hot
conditions return on Saturday as the front moves back north.

Sunday into next week, larger upper waves moving through will keep
chances for rain around. Cooler air will filter back into the area,
with highs by Tuesday in the upper 70s to middle 80s.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 145 AM EDT Wed Sep 16 2026

Impacts:

- Convection will be around this morning, mainly at KLAF

- Additional isolated to scattered convection possible this
  afternoon

- Variable winds, especially early in the period

Discussion:

Initial convection should be out of KLAF by valid time, and most
convection should remain northwest of KLAF for much of the predawn
hours. More convection will move into the KLAF area around 12Z but
should exit by afternoon.

Otherwise, confidence in convection is low. Numerous outflow
boundaries may trigger an isolated shower early this morning at the
other sites. This afternoon, isolated to scattered convection will
develop, but where they do is uncertain thanks in part to those
boundaries. The boundaries will also keep wind direction variable.

Outside of convection, odds favor VFR conditions.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

AVIATION...50
DISCUSSION...50