770
FXUS63 KIND 310641
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
241 AM EDT Mon Aug 31 2026

.KEY MESSAGES...

- Patchy sprinkles possible through this morning. Otherwise
partly sunny and warm today.

- Increasingly hot and humid conditions through the middle of this
week. Heat index values on Tuesday and Wednesday may reach the low
100s.

- Isolated to scattered thunderstorms will be possible at times
  Thursday through the weekend.

&&

.DISCUSSION (Today through Sunday)...
Issued at 241 AM EDT Mon Aug 31 2026

Surface analysis early this morning shows strong high pressure off
the Carolina coast, providing warm and humid southerly flow within
the lower levels. A frontal boundary was found from western MN
across NB to KS and the TX panhandle. Aloft, water vapor showed
ridging in place over upper midwest. a plume of tropical moisture
continued to stream across the American SW to NB and MN before
diving SE to IN/OH and NY. This upper level moisture continued to
produce the high cloud cover across Central Indiana.

Today and Tonight...

More dry weather is expected today and tonight as forecast soundings
suggest dry lower and middle levels with the warm but humid S-SW
flow in place. Forecast soundings show the upper level moisture
continuing to linger across the area through the day, but clearing
tonight as the steering flow aloft becomes more westerly, pushing
those high clouds across the Great Lakes instead of into Indiana.
Thus a partly sunny day and a mostly clear night will be expected.
Again highs around 90, persistence, will be expected. Warmer temps
will be possible across southern parts of Central Indiana where
cloud cover will be less substantial.

Tuesday and Wednesday...

Hot and humid weather looks in store for both Tuesday and Wednesday.
Strong upper level high pressure will be stretching across the
southern plains and Ohio Valley, keeping cloud cover and the upper
flow across the Great Lakes. Forecast soundings on both days suggest
a very dry and very hot column, with 700mb temps near 12C. Surface
high pressure anchored over the southeastern states will continue to
provide hot and humid southerly flow. 850mb temps near 22C will
allow for highs in the mid 90s on Tuesday and Wednesday. Should
this stay the course, Heat advisories will be needed.

Thursday through Friday...

Weak ridging within the upper flow is expected to build across the
upper midwest, allowing NW flow to begin to develop across Central
Indiana by Friday. Strong upper level high pressure will be centered
over KS and MO. A weak wave is suggested to pass across northern
Indiana on Thursday, followed by a stronger wave on Friday afternoon
into Friday Night.

A weak frontal boundary will be in the vicinity of Central Indiana
on Thursday, passing south of our area on Friday Night. This along
with an expected hot, humid and unstable air mass in place will
continue the need for at least chance pops during that time.

Saturday and Sunday...

The strong upper level high pressure system is suggested to
strengthen and retrograde west on Saturday into Sunday, centering
over western KS and eastern CO. This will result in a strong ridge
over the CONUS, with monsoon like Pacific flow arriving over So Cal
and NV before shooting north to Montana and Central CA before before
turning quickly south the western Great Lakes into Indiana. Again,
embedded waves within this flow are expected to ridge ride to
Indiana, providing some upper support. Lee Side flow will provide
some subsidence across the eastern Great Lakes, resulting in a
stronger surface high there, and should the earlier front make it
far south, cooler easterly flow arriving across Central Indiana for
Saturday and Sunday. At the moment, forecast soundings show best
saturation on Saturday Night, with a cooler and dry sounding on
Sunday. Thus for now, pops will be needed on Saturday and Saturday
Night, and confidence remains low for Sunday.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1121 PM EDT Sun Aug 30 2026

Impacts:

- None expected.

Discussion:

VFR conditions are expected through the period.

A fast moving upper flow across northern Indiana and the Great Lakes
will continue to generate mid and high clouds. A sprinkle is
possible but confidence and coverage looks to be so low, that it is
not a worthy mention in the TAFs at this time.

A few cumulus will be possible on Monday, but any cigs will remain
VFR.

Clouds should shift farther north tonight along with the expected
upper flow that should shift north also.


&&

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

$$

AVIATION...Puma
DISCUSSION...Puma