083
FXUS63 KIND 190713
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
313 AM EDT Wed Aug 19 2026

.KEY MESSAGES...

- Patchy fog possible through daybreak with additional fog
  development possible late tonight

- Scattered to numerous showers and storms are expected this
  afternoon into tonight

- Localized flash flooding will be possible this afternoon into
  tonight, isolated severe storms are also possible

- Generally drier late this week through early next week, but there
  is a chance for showers and storms late Friday into Saturday

&&

.DISCUSSION (Today through Tuesday)...
Issued at 312 AM EDT Wed Aug 19 2026

Today through tonight...

Patchy fog will be possible through daybreak as winds remain very
light across central Indiana. Any fog that develops should quickly
mix out in typical diurnal fashion. Regional radar mosaic depicts an
MCS currently moving across eastern MO and western IL. This system
will continue to propagate southeastward along an instability
gradient, keeping precipitation mostly confined to southwest
portions of the forecast area through the morning. Isolated
thunderstorms cannot be ruled out given weak elevated instability.

Greater chances for convection are expected this afternoon into
tonight as a mid-upper level wave pushes across the region. At the
surface, a weak west to east oriented cold front should gradually
push south providing greater low-level convergence. These
features along with daytime heating over an abundantly moist
environment supports the potential for scattered to numerous
showers and thunderstorms. Convection could continue well into the
overnight, but expect generally decreasing coverage late tonight
as the the strongest forcing shifts east.

Deep-layer wind shear is supportive for organized convection, but
there remains some uncertainty on the degree of destabilization
later today which limits confidence on the overall severe threat.
Isolated damaging wind gusts or severe hail appear possible if
sufficient destabilization occurs as favorable deep-layer wind shear
could support multicell line segments and possibly even a few
transient supercells.

The greater concern appears to be localized flash flooding given
soils remain very saturated from recent rainfall. Model guidance
continues to suggest the potential for training storms with the west
to east oriented cold front slowly pushing south. Warm rain
processes and PWATs around or over 2 inches will also promote
efficient rainfall rates. Latest CAMs generally suggest the
potential for 1 to 3 inches of rain where training occurs.
Additional fog development is possible late tonight once convection
dissipates.

Thursday through early next week...

Surface high pressure building in will provide mostly quiet weather
conditions Thursday and Friday. A few upper level disturbance will
move in late Friday into Saturday supporting at least low rain
chances with sufficient moisture advecting into central Indiana.
Long range guidance generally depicts surface high pressure building
in once again late weekend into early next week providing mundane
weather conditions. Expect temperatures to remain slightly below
normal during the period.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 312 AM EDT Wed Aug 19 2026

Impacts:

- Patchy fog possible at LAF, HUF, BMG through 12Z today.

- Scattered to numerous showers and thunderstorms possible, mostly
  after 18Z.

Discussion:

Patchy fog is possible through 12Z today, mainly at the outlying TAF
sites. A shortwave trough approaching from the northwest is expected
to bring scattered to numerous showers and thunderstorms to central
Indiana this afternoon into the evening hours. Some uncertainty
remains regarding timing, and thus a Prob30 group was included to
cover this potential initially after 18Z.

A TEMPO was included for some sites from 00-04Z this evening when
greater coverage can be expected. Convection could linger during
much of the overnight, but uncertainty remains. Fog development also
appears possible late overnight if convection clears out. Winds
should increase from the WSW as the shortwave approaches later today
with speeds remaining under 10kt. Look for winds to become
northeasterly tonight.

&&

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

$$

AVIATION...Melo
DISCUSSION...Melo