415
FXUS63 KIND 011238
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
838 AM EDT Tue Sep 1 2026

.KEY MESSAGES...

- Heat Advisory in effect for all of central Indiana from Tuesday
  afternoon through Thursday evening

- Increasingly hot and humid conditions through the middle of this
  week. Peak heat index values up to 105 are possible each afternoon
  Tuesday through Thursday.

- Isolated to scattered thunderstorms will be possible at times
  late this week through the weekend.

&&

.FORECAST UPDATE...
Issued at 838 AM EDT Tue Sep 1 2026

The northern apex of the upper ridge still resides north of the
central Indiana, keeping weak convection out of the area. That said,
cold pools within this convection will slowly sink soouth this
morning, creating some extended cloud cover into N/NE portions of
central Indiana from the late mornging through the early afternoon.
This may have some minor impacts to forecast highs by limiting
temperature gains by a degree or two.

No other significant updates were needed to the ongoing forecast.

&&

.DISCUSSION (Today through Monday)...
Issued at 305 AM EDT Tue Sep 1 2026

Dry and hot weather conditions are expected through at least
Thursday as ridging and surface high pressure are impacting the
region. The surface high will place persistent southerly to
southwesterly flow for central Indiana, allowing increasing hot and
humid conditions. Highs are expected to be in the 90s through at
least Thursday (possibly lingering into the start of the holiday
weekend) with heat indices up to 105. Overnight lows will likely
only drop to the 70s, providing little relief. A heat advisory is in
effect from this afternoon through most of the day Thursday. Drink
plenty of fluids, limit time outdoors during peak heating, and check
up on relatives and neighbors.

Models show that the ridge will start to shift towards the end of
the week, but uncertainty ramps up from Friday and beyond as the
development of the upper pattern becomes questionable in the
details. Overall, the upper high looks to get pushed west as an
omega block pattern sets up across the country.

However, questions arise on the strength and locations of the upper
troughs/lows on either side of the high across the central part of
the country. This will have an impact on storm tracks and how much
cooler air (cooler being a relative term) moves into the area.

For now, will allow a gradual cooldown from highs in the 90s on
Friday to highs mainly in the 80s by Labor Day. Will have low PoPs
at times at least through Sunday, but confidence is quite low on the
specifics of these.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 644 AM EDT Tue Sep 1 2026

Impacts:

- None expected

Discussion:

VFR conditions will continue through the period, with high clouds
from time to time. A few cumulus may pop up again today.

Southwesterly winds may gust around 15kt this afternoon.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 2 PM this afternoon to 8 PM EDT Thursday for
INZ021-028>031-035>049-051>057-060>065-067>072.

&&

$$

UPDATE...Updike
AVIATION...KF
DISCUSSION...KF/50