437
FXUS63 KIND 081810
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
210 PM EDT Mon Jun 8 2026

.KEY MESSAGES...

- Scattered showers/t-storms this evening and Overnight.
  Isolated flooding possible

- Humid and very warm this week...daily rain chances continue
  through Friday...readings near 90F on Wednesday and Thursday

- Slightly cooler weather for the weekend with lower rain chances

&&

.DISCUSSION (This evening through Monday)...
Issued at 209 PM EDT Mon Jun 8 2026

Surface analysis this afternoon shows warm and humid southerly flow
in place across Central Indiana. This was due to low pressure over
western KS, and strong high pressure found over Upstate NY. Water
vapor shows an upper trough over the middle Mississippi river
valley. A tropical plume of moisture was found streaming northward
ahead of the trough across TN/KY and IN. Showers and storms were
found across IL and southern Indiana, pushing northeast.

Tonight and Tuesday...

Models suggest the upper trough to the west will continue to
progress northeast toward Indiana, passing mainly during the
overnight hours. Forecast soundings show a deeply saturated column
this evening and overnight as the moderate forcing arrives with a
very moist air mass in place. Given the high pwats over 1.8 inches,
heavy rain will be possible. Diurnal heating will add to
thunderstorm coverage this afternoon, but will be diminished by late
evening as heating is lost. Still Central Indiana should expect
showers overnight as the best forcing from the upper trough axis
arrives. Very high pops will be use.

As the upper trough exits on Tuesday, forecast soundings begin a top
down drying. But lower level moisture will remain. Although this
will end the limit the precipitation fop the rest of the day, chances
will return during the afternoon due to the lack of change of
airmass. Forecast soundings on Tuesday afternoon suggest steep lapse
rates with plentiful CAPE and attainable convective temperatures.
Thus chances for more diurnal showers and storms late in the
afternoon and into the evening will be needed. Highs in the middle
80s will be expected.

Wednesday...Hot and humid weather will be expected as southerly flow
will continue to allow humid gulf air to reside across central
Indiana. A passing ridge aloft will provide subsidence and moderate
pressure gradient will provide good mixing on southwest winds. This
should allow high to reach the upper 80s to around 90, which could
be the hottest day of the summer thus far. At this point values are
not at hot enough levels for mentions of heat advisories.

Thursday through Monday...

The upper pattern through this period will transition from southwest
flow across Indiana on Thursday and Friday to more of a broad
cyclonic west-northwest flow for Saturday through Monday. This is
due to the expected breakdown of upper ridging over the eastern US
and the gradual arrival of a broad upper low pushing across Canada.

On Thursday, the warm and humid air mass will remain across Indiana.
This will keep some diurnal showers and storms across our area.
Better chances for rain will arrive on Thursday Night into Friday as
a cold front passing will provide additional forcing. Forecast
soundings show drier air and subsidence arriving across the area on
Friday afternoon in the wake of the cold front. Thus highest pops
will be Thursday Night into Friday morning. At the moment, dry
weather looks to arrive fro Friday afternoon.

The dry weather looks to continue through much of the weekend as the
upper flow becomes more west-northwest, allowing a cooler and less
humid air mass to arrive.  Small chances for rain are currently in
play on Sunday as a secondary, weak, and quick moving cold front
passes. However, confidence is low with this feature as available
moisture remains in question.

For the moment, Monday looks dry and cooler as Canadian high
pressure arrives from the northwest.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 128 PM EDT Mon Jun 8 2026

Impacts:

- MVFR CIGS with scattered -SHRA/TSRA will be possible this
afternoon and evening. Downpours possible.
- Iso/Sct SHRA continues overnight with MVFR Cigs

Discussion:

MVFR conditions are expected the next 24 hours as an upper trough
pushes across the area. This afternoon, best rain chances will be
found across the Wabash Valley. Other scattered showers and storms
will be possible near IND and BMG through the late afternoon and
into the evening due to diurnal heating. Confidence for precise
timing and locations is remains low.

Thus large windows of VCSH and VCTS will be used through the day.
Areal coverage of showers and storms will diminish this evening as
heating is lost, but as the upper trough will still be in the
vicinity, a few showers and storms will still be possible.

Forecast soundings suggest drier air and subsidence arriving after
14Z on Tuesday. Although cigs will remain at that time, best rain
chances end at that time.


&&

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

$$

AVIATION...Puma
DISCUSSION...Puma