341
FXUS63 KIND 130656
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
256 AM EDT Sat Jun 13 2026

.KEY MESSAGES...

- Showers and thunderstorms likely late Saturday, with severe
  weather possible Saturday night into Sunday.

- Much cooler temperatures on Monday with highs in the 70s.

- Unsettled weather with near normal temperatures next Tues-Thurs.

&&

.DISCUSSION (Today through Friday)...
Issued at 255 AM EDT Sat Jun 13 2026

Synoptic analysis shows broad troughing over Canada with a roughly
zonal jet stream crossing the northern CONUS. Surface high pressure
currently resides over Indiana, with broad subsidence leading to
clear skies and light winds.

High pressure slides eastward today, allowing surface winds to
become southerly. This should promote moisture advection northward,
with dew points climbing gradually throughout the afternoon and
evening hours.

To the west, a cluster of strong thunderstorms is located over
southern kansas and northern Oklahoma. Guidance shows an MCV
emerging from this cluster, which is expected to generate a
secondary round of convection across Missouri this afternoon. A few
showers and perhaps a thunderstorm may develop over Illinois and
extend into central Indiana, associated with the leading edge of
deeper moisture advection. Guidance is in poor agreement regarding
this initial round of showers or storms, so probability of
occurrence is rather low. Slight to chance PoPs will be carried
during the afternoon hours mainly across western Indiana.

A more potent vort max embedded within the zonal flow to our north
arrives late Saturday into Sunday. Combined with the MCV, convection
upstream over Missouri and into Iowa likely consolidates into a line
which then propagates southeastward. Should an MCS develop, it will
be aided by rich moisture advection ahead of it and easterly deep
layer shear to promote cold pool updraft balance. Shear diminishes
with eastward extent, however, so the likelihood of a strong MCS is
greater across western portions of the area. The MCS could just as
well pass southwest of our forecast area with little impacts.

Guidance has been struggling to resolve this due to the relatively
modest forcing and lack of a distinct triggering mechanism (like a
strong cold front). As such, convective evolution depends on cold
pool dynamics which numerical models have difficulty resolving. As
such, the predictability of convective evolution into Indiana will
remain low even within the very near term.

We will maintain chance to likely PoPs across the area, as even with
an MCS or lack thereof it still looks like showers associated with
the vort max are probable Saturday night into Sunday morning. In
terms of severe potential, upscale growth into a southeastward
propagating MCS will lead to damaging wind gusts becoming the
primary hazard. Large hail is possible with discrete convection,
which is more probably during the afternoon over Illinois but could
sneak into western Indiana.

Low clouds and dreary conditions persist into Sunday, with scattered
showers and perhaps additional thunderstorms, until the system`s
cold front arrives. This front, which lags behind the best forcing
and moisture, could pass through without much fanfare Sunday
afternoon. Some models depict a few showers and thunderstorms along
the front itself though these are outliers as of the 06z model
suite.

Once the front has passed, expect clearing skies as high pressure
returns. Multiple days of cooler-than-normal temperatures are likely
as broad troughing remains aloft. Active weather may return midweek
as embedded waves pivot around the larger-scale trough. These waves
are difficult for guidance to resolve this far out, but there seems
to be a loose signal pointing at the Tuesday evening to late
Thursday timeframe.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 133 AM EDT Sat Jun 13 2026

Impacts:

- Low chance for showers and isolated storms Saturday afternoon
- Increasing chance of showers/storms after 06z
- MVFR ceilings likely after 06z Sunday, IFR possible towards end of
  TAF period

Discussion:

VFR conditions are expected today, with a low chance of isolated
showers after 21z as a mid-level system and cold front approach from
the west.

Shower chances, as well as thunderstorms, increase after about 06z
Sunday. Abundant low-level moisture advection should promote
widespread MVFR ceilings towards the end of the TAF period. There is
potential for IFR ceilings by daybreak Sunday.

Winds remain light out of the south or south-southwest today,
increasing to about 10kt this afternoon. Winds diminish after 00z.
Thunderstorms, should they occur, may produce brief variable wind
gusts over 30kt. As of this update, the probability of occurrence is
too low to include in the TAFs.


&&

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

$$

AVIATION...Eckhoff
DISCUSSION...Eckhoff