Flash Flood Warning 26, NWS Indianapolis, IN

Area Forecast Discussion
National Weather Service Indianapolis IN
254 PM EDT Sat Jun 27 2026

.KEY MESSAGES...

- Flood Watch continues through early this evening for far southwest
  central Indiana

- Thunderstorms producing heavy rainfall and localized flooding will
  focus across southern Indiana into this evening

- A few storms could become severe mainly across the southwest half
  of central Indiana into this evening

- Hot and humid conditions expected for much of next week with
  multiple days in the 90s and heat indices over 100 degrees

&&

.DISCUSSION (This evening through Saturday)...
Issued at 253 PM EDT Sat Jun 27 2026

Rest of This Afternoon through This Evening...

A surface front will meander across the southern half of the
forecast area through tonight. An MCV was across southeast Missouri
this afternoon, and this will move east across southern Indiana this
evening.

Temperatures in the middle 70s to around 80 and dewpoints in the
lower to middle 70s (across areas near and south of the front) have
helped produce instability across the area.

The combination of the front and the MCV will produce scattered to
numerous showers and thunderstorms, with the most coverage across
the southern half of central Indiana, where the best instability and
forcing will be. Will have some likely PoPs across this part of the
area, with lower PoPs to the north.

With the instability and shear enhanced by the MCV, some severe
storms are possible into this evening across the south.

The atmosphere remains quite moist south of the front. Current wind
fields support slower storm motions. Convergence associated with the
front and MCV will support bands of convection, which could result
in training of storms. Thus, heavy rain remains a threat as well.

The far southwest forecast area had over 2 inches of rain in the 24
hours ending this morning, so extended the Flood Watch there until
00Z. Elsewhere across the south, localized flooding remains a threat
but less rain had fallen there, so ended the watch.

Overnight through Sunday Night...

Without the support of the MCV, coverage of rain will greatly
diminish overnight. Winds will be light, and moisture will linger.
This will allow some fog to form once again for parts of the area.

On Sunday into the Sunday night, the surface front will return
northeast as an upper ridge builds into the area. This may trigger
an isolated shower or storm, so kept some slight chance PoPs for
parts of the area during the day Sunday. For now, went dry Sunday
night with the ridge building in. If the ridge is slower than
expected, showers and storms riding around it Sunday night may clip
the area.

Lows tonight will be in the mid 60s to lower 70s. With the ridge
building in and more afternoon sunshine expected on Sunday, highs
will be in the middle and upper 80s.

Monday and beyond...

An upper high/ridge will be the main influence across central
Indiana during next week. For Monday through Wednesday, the high
will be enough to keep the threat for rain below mentionable
thresholds.

As early as Thursday, uncertainties in the location of the
high/ridge are enough that isolated/scattered convection can't be
ruled out. Confidence is low though in any rain Thursday into Friday
as the ridging might still be strong enough to suppress convection.
However, by next weekend it appears the ridge will be far enough way
to allow convection to pop up from daily instability or from
impulses riding around the ridge.

The main concern during this period will be the heat. Temperatures
will peak in the lower to perhaps middle 90s, and dewpoints will be
in the 70s. These will produce heat indices over 100 and perhaps
even over 105 (especially in the very moist areas in the southwest).
Blended guidance looks too high with dewpoints though, so will lower
some.

Strict Heat Advisory criteria may not be met, but a long period of
near Advisory criteria will likely require a multi-day Advisory at
some point nonetheless. Will continue to message it will be hot
regardless of headlines.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 116 PM EDT Sat Jun 27 2026

Impacts:

- Brief VFR possible this evening, otherwise MVFR through 06Z

- IFR and worse conditions developing after 06Z in stratus and
  fog

- Scattered convection this afternoon into the evening

Discussion:

Ceilings will continue to lift this afternoon and could become VFR
for a period this evening. Otherwise, during the night ceilings will
fall once again in the moist atmosphere, with IFR and worse
conditions developing again mainly after 06Z Sunday. Fog will
develop again as well. Slow improvement will occur Sunday morning.

Scattered convection will develop this afternoon and will persist
into the evening. Isolated convection cannot be ruled out on Sunday,
but odds are too low to mention.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 8 PM EDT this evening for INZ067>069.

&&

AVIATION...50
DISCUSSION...50

Hazardous Weather Outlook
National Weather Service Indianapolis IN
319 PM EDT Sat Jun 27 2026

INZ021-028>031-035>049-051>057-060>065-067>072-281930-
Carroll-Warren-Tippecanoe-Clinton-Howard-Fountain-Montgomery-Boone-
Tipton-Hamilton-Madison-Delaware-Randolph-Vermillion-Parke-Putnam-
Hendricks-Marion-Hancock-Henry-Vigo-Clay-Owen-Morgan-Johnson-Shelby-
Rush-Sullivan-Greene-Monroe-Brown-Bartholomew-Decatur-Knox-Daviess-
Martin-Lawrence-Jackson-Jennings-
319 PM EDT Sat Jun 27 2026

This hazardous weather outlook is for central Indiana.

.DAY ONE...Through Tonight.

Scattered to numerous showers and thunderstorms will continue into
the evening, then only isolated thunderstorms are possible overnight.

A few thunderstorms this afternoon and evening may produce damaging
winds, focused across the southwest half of central Indiana. Heavy
rainfall producing flooding will remain the primary concern.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Afternoon heat indices will rise into the 90s on Sunday then above
100 degrees for much of next week.

Chances for thunderstorms return Thursday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated but any reports of flooding
through tonight would be appreciated.

&&

More information, along with other weather, hydrological and climate
information can be found at http://weather.gov/ind

Preliminary Local Storm Report
National Weather Service Indianapolis IN
404 PM EDT Sat Jun 27 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0315 PM     Flash Flood      2 WNW Dugger            39.08N 87.29W
06/27/2026                   Sullivan           IN   911 Call Center

            Indiana Route 54 flooded out east of
            Sullivan. Time estiamted.

&&

AGM

Preliminary Local Storm Report
National Weather Service Indianapolis IN
412 PM EDT Sat Jun 27 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0315 PM     Flash Flood      Linton                  39.04N 87.17W
06/27/2026                   Greene             IN   911 Call Center

            Flooding in Linton Lyons and Switz City
            including stalled vehicles in Linton.
            Floating RxR ties. Time estimated.

&&

AGM