946
FXUS63 KIND 121729
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
129 PM EDT Fri Jun 12 2026

.KEY MESSAGES...

- Cooler and less humid today, with highs in the lower 80s.

- Showers and thunderstorms likely late Saturday, with severe
  weather possible over southwestern central Indiana.

- Much cooler temperatures for the first half of next week.

&&

.FORECAST UPDATE...
Issued at 1010 AM EDT Fri Jun 12 2026

Forecast evolving as expected this morning as small area of surface
high pressure builds east from central CONUS into Midwest/OH through
the day...providing downward trend in humidity amid west-northwest
breezes under clearing skies.  A few gusts up to 15-20 mph today,
mainly north/east of Indianapolis. A pleasant early summer day
with dewpoints falling into the 55-60 degree range and peak
temperatures in the low 80s across central Indiana.

&&

.DISCUSSION (Today through Thursday)...
Issued at 314 AM EDT Fri Jun 12 2026

Thunderstorms persist across the southern half of our CWA as what
remains of an earlier severe MCS pushes southward. This activity
should come to an end within the next few hours. Severe weather is
no longer expected.

Low amplitude upper-level troughing moves into the Great Lakes
region today. Northwesterly flow at the surface within a post-
frontal environment should lead to a noticeable air mass change.
Combined with surface high pressure arriving, expect clearing skies,
cooler temperatures, and lower humidity today.

Surface high pressure exits eastward on Saturday with southerly low-
level flow returning. Simultaneously, a vort max racing eastward
within a zonal jet stream arrives late Saturday. This feature likely
triggers shower and thunderstorms upstream, mainly over Illinois.

A limiting factor for eastward progression is the aforementioned
surface high pressure. The surface high exits early Saturday, and
there simply may not be enough time to advect moisture/instability
northward into Indiana. Guidance currently depicts sufficient
moisture return over Illinois extending to the IN/IL state line from
Terre Haute southward. Should upstream convection develop, it could
consolidate into a southeast-propagating line that follows the
moisture/instability gradient. This favors the western and
southwestern portions of our CWA.

In terms of severe weather potential, instability is the limiting
factor over Indiana. Model soundings show relatively long hodographs
with mean shear vectors pointing southeastward. Assuming greater
instability is realized, initial development may be capable of
producing large hail. As storms consolidate along developing cold
pools, they should propagate southeastward in line with the shear
vector and along the instability gradient. Damaging wind gusts would
become the primary hazard after this occurs. The best chance of any
of this happening is across Illinois, where available instability is
less in doubt. Across Indiana, again, our southwestern counties have
the best chance of severe weather late Saturday into Saturday night.

Further north, showers and a few thunderstorms still likely even
with the lower severe potential. Chance to likely PoPs will be
included for most of central Indiana.

Broad upper-level troughing persists through the weekend and into
next week. Weak surface high pressure returns with quiet weather and
cooler-than-normal temperatures through mid next week. Another wave
embedded within the broader trough may swing through mid week with
another chance of shower/storms, but it`s too far out to pin point
exact timing.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 129 PM EDT Fri Jun 12 2026

Impacts:

- Gusty W-NW winds this afternoon from 15-20 kts

Discussion:

VFR Conditions through the period. Mostly clear skies presently
across central Indiana thanks to the high pressure building into the
region from the NW. Deeper mixing than earlier forecast has allowed
for wind gusts from the W-NW from 15-20 kts to develop in the last
hour. Have included gusts except for KBMG through 23Z.

Overnight as high pressure builds into central Indiana, winds will
become light and variable. Skies also be clear. Increasing high and
eventually mid level clouds will occur on Saturday ahead of a storm
system over the plains moving towards the MS valley. A few light
showers out of a mid deck of clouds are expected around KIND during
the mid-late afternoon. So have included VCSH for this reason.

&&

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

$$

UPDATE...AGM
AVIATION...Crosbie
DISCUSSION...Eckhoff