266
FXUS63 KIND 211716
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
116 PM EDT Fri Aug 21 2026

.KEY MESSAGES...

- Areas of fog early this morning...especially in low-lying areas

- Isolated/scattered showers and a few t-storms are possible late
  Friday night...and again Saturday afternoon, mainly east

- Milder/less humid Saturday night through Tuesday...highs mainly 75-
  80F, lows mainly 55-60F.

&&

.FORECAST UPDATE...
Issued at 953 AM EDT Fri Aug 21 2026

A couple of small patches of fog continue to mix out this morning as
heating begins in earnest. Obs trends and latest near term guidance
suggests we`re a bit low on high temperatures this afternoon, and
have bumped maxes up a degree or two across the board.

Aside from some fair weather cumulus, expect minimal cloud cover
through the day under high pressure. Winds will be relatively light
and occasionally variable as the high moves overhead.

&&

.DISCUSSION (Today through Thursday)...
Issued at 309 AM EDT Fri Aug 21 2026

Areas of reduced visibility in fog and patchy dense fog will
dissipate early this morning amid light and variable winds.
Lingering stratus should transition to diurnal cumulus by midday.
Seasonably strong surface high pressure sliding east into New
England...will drag its weaker southwestern corner/axis across
central Indiana. Meanwhile a mid-level weakness will round the
southern side of a Canadian upper trough into the Midwest... with
dewpoints overall trending higher to end the workweek. H850
temperatures around only 15 degrees Celsius will allow for near to
slightly below normal high temperatures in the low to mid-80s,
although this milder trend will still feel summery by late day given
the increasing humidity.

Increasing upper troughing from Great Lakes to eastern North America
this weekend through the long term will suppresses hot/humid
subtropical ridge well to our south/west...with an overall
noticeably drier pattern through at least next Tuesday....although
lower chances of RWs are on the table for late tonight, and more so
eastern counties Saturday afternoon...ahead of more September-like
conditions early next week.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 116 PM EDT Fri Aug 21 2026

Impacts:

- Isolated to scattered showers and storms late tonight into
  Saturday morning
- Low chance for brief fog at outlying sites Saturday morning

Discussion:

Diurnal cu field has formed across much of central Indiana early
this afternoon and will linger through late day. An axis of mid
level clouds drifting out of northern Illinois should expand into
the area by early evening...with increasing cloud cover overnight in
advance of an upper level wave and associated cold front. Scattered
convection will move across central Indiana mainly after 06Z with
additional showers possible in the immediate vicinity of the frontal
boundary Saturday morning. Will handle with PROB30s at all terminals
late tonight and early Saturday considering the scattered coverage
and low to medium confidence on impacts. Clouds will scatter once
the front passes by midday Saturday.

Generally light and variable flow is expected through the first half
of tonight then becoming southwest in the predawn hours as the front
approaches. Once the front passes Saturday morning...winds will veer
to northwest and increase to around 10kts. A few gusts at 15 to
20kts will be possible as well.

&&

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

&&

$$

UPDATE...Nield
AVIATION...Ryan
DISCUSSION...AGM