698
FXUS63 KIND 261040
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
640 AM EDT Wed Jun 26 2024

.KEY MESSAGES...

- Showers and thunderstorms will be around at times today.
- An isolated strong to severe storm is possible south today.
- A brief respite from heat and humidity Thursday and Friday before
  another warm up and additional storm chances late Friday through
  the day Saturday.

&&

.SHORT TERM (Today and tonight)...
Issued at 300 AM EDT Wed Jun 26 2024

Another lower confidence forecast for today as mesoscale features and
smaller scale upper features make predicting convective coverage
more difficult.

Early This Morning...

An apparent small MCV looks to be moving into southwest
Indiana/western Kentucky. Lingering CAPE resides across southern
portions of the forecast area, and this MCV is using that energy to
pop up some convection across the far southwest part of the area.
Some gusty winds and small hail are possible with these given the
instability.

Meanwhile, isentropic lift is ongoing across the remainder of
central Indiana, and this is resulting in isolated convection.
Instability is much less here. Thus, convection is weaker and not
lasting too long when it forms.

Given the above, will go with likely or high end chance category
PoPs across the south third or so as the MCV works its way east
northeast. Elsewhere, will go with lower PoPs to account for the
weaker convection.

Today...

Weaker broad upper forcing will continue early in the Today period,
but there may be other smaller convectively induced upper
perturbations around. Will keep some mainly chance PoPs around
during the morning.

A larger scale upper trough will move in for the afternoon along
with a surface cold front. This forcing will interact with the
moisture across the area to produce some showers and thunderstorms.

Questions remain on how much instability can build and whether any
convection that forms farther southwest can rob some of the deeper
moisture. This uncertainty can be seen in the differing CAM
solutions.

For now will go with likely or higher PoPs across the area, but with
low to medium confidence.

Highest instability still looks to be across the southern forecast
area, so this would be where the best chance for an isolated strong
to severe storm could develop.

Temperatures will be cooler thanks to clouds and rain, with highs in
the upper 70s to middle 80s.

Tonight...

By the start of the Tonight period (00Z), a few showers or storms
may be lingering in the far south. Will go with some low PoPs there
early. Otherwise, clouds and wind speeds will decrease.

Boundary layer may remain relatively moist if rain is widespread
today. This could result in some patchy fog late tonight.

Lows will be in the upper 50s to lower 60s.

&&

.LONG TERM (Thursday through Tuesday)...
Issued at 300 AM EDT Wed Jun 26 2024

The long term will see a back and forth between quiet weather with
pleasant temperatures and heat with storm chances as multiple
systems move through the region.

The period will start out quiet with surface high pressure bringing
near normal temperatures and dew points in the upper 50s to low 60s.
As the weekend approaches, moisture will return followed by WAA due
to an upper wave and associated front move through the area. Showers
and storms may arrive as early as Friday evening and potentially
lasting into Sunday morning. Periodic breaks in the rain may be
possible with best chances for storms being early Saturday morning
through the afternoon hours as the front itself approaches. Daytime
heating (with highs in the upper 80s to low 90s) and increasing
moisture advection ahead of the front is expected to promote
moderate destabilization. This, combined with weak to modest
effective bulk shear, may support a few strong to severe storms. The
primary threat would be isolated damaging wind gusts, but
localized flooding or severe hail cannot be ruled out.

Behind the weekend system, below normal temperatures and near to mid
50s dew points will provide a brief break for the start of the new
week. The next system, arriving towards mid next week, will return
heat and more storm chances.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 640 AM EDT Wed Jun 26 2024

Impacts:

- Scattered showers and storms this morning
- Potential line of convection this afternoon
- Potential for MVFR or worse conditions in thunderstorms
- Wind shift to northwest during the day

Discussion:

Low confidence forecast once again as convection will rely on small
forcing features early, and this convection will impact chances for
convection this afternoon. Outside of convection, VFR is expected.

A small upper level feature will move north across the area this
morning, bringing some showers and scattered storms. Used a VCSH
mention for now and will update if storms become more widespread.

Another round of convection should develop ahead of a boundary this
afternoon. How widespread the convection remains uncertain due to
effects from clouds/overnight convection. Used TEMPO north and
PROB30 south, but again confidence is low.

&&

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

$$

SHORT TERM...50
LONG TERM...KF
AVIATION...50