Flash Flooding in Indiana, June 29 to 30, 2025

Area Forecast Discussion
National Weather Service Indianapolis IN
658 PM EDT Sun Jun 29 2025

.KEY MESSAGES...

- Rain/storm chances persist through Monday night with the
  greatest coverage during the afternoon and evening hours

- Localized flooding is the primary threat through Monday night,
  but isolated strong wind gusts are also possible Monday
  afternoon and evening

- Drier and slightly cooler weather expected towards the middle of this
  week before more humid conditions return Friday into next weekend

&&

.SHORT TERM (This Evening through Monday Night)...
Issued at 253 PM EDT Sun Jun 29 2025

Yet another afternoon with scattered convection over the region with
a moist and unstable airmass in place. 18Z temperatures are lower
than the last several days courtesy of the convection and plentiful
cloud coverage...running generally in the low to mid 80s.

Unsettled weather will continue through Monday as a series of upper
level waves track through the Ohio Valley followed by a cold front
Monday night. Periodic showers and thunderstorms will persist as a
result...with highest coverage expected Monday afternoon and
evening.

Showers and storms are pockmarked across the forecast area this
afternoon and will likely increase in coverage over the next few
hours as instability levels peak. The KIND ACARS sounding shows poor
lapse rates present through the column...meaning stronger winds from
collapsing downdrafts are likely to be less of a concern into the
evening. The greatest impact remains the potential for localized
flooding from slow moving convection producing torrential downpours.
PWATs are already near 2 inches and are likely to tick up further
into the evening. Best potential for storms remains across the
southern half of the forecast area where deepest moisture resides
but convection really could pop up anywhere across central Indiana.

The loss of diurnal heating this evening should lead to convective
coverage diminishing but that respite is expected to be brief and
last only into the early overnight. The first of the series of upper
level waves associated with a broader trough aloft will arrive
during the predawn hours with scattered convection increasing yet
again prior to daybreak. This will parlay into Monday as the
combination of the forcing aloft with an approaching cold front will
interact with the moist unstable airmass across the Ohio Valley for
numerous to widespread convection peaking during the afternoon and
evening.

The risk for a few storms producing damaging winds is greater by
late day with the infusion of slightly better BL shear present
immediately ahead of the upper trough axis but an overall skinny and
elongated CAPE profile with unidirectional shear profiles is
supportive of a generally messy multicellular convective mode for
the afternoon and evening. Heavy rain and localized flooding will
remain primary concerns as well. Showers and storms will continue
into Monday night ahead of the frontal boundary with rain ending
from west to east overnight as the front sweeps off to the east.

Temps...lows tonight will fall mainly into the lower 70s. Highs are
expected in the mid 80s on Monday. As cooler air advects into the
region behind the frontal passage Monday night...lows will drop into
the mid and upper 60s.

&&

.LONG TERM (Tuesday through Sunday)...
Issued at 253 PM EDT Sun Jun 29 2025

Unsettled weather for the early part of this week will shift
east Tuesday morning as a drier and slightly cooler airmass builds
in courtesy of broad surface high pressure and drier northwest flow
aloft. Upper level ridging will return by late next week with a
likely return to isolated to scattered diurnal convection Friday
into the weekend as a hotter and more humid airmass reestablishes
across the Ohio Valley.

Tuesday through Thursday..

Other than a few lingering showers Tuesday morning...mostly quiet
weather conditions are expected Tuesday through Thursday as high
pressure settles across the region. Dewpoints will finally fall back
into the lower and middle 60s and perhaps even down into the upper
50s in northern portions of the forecast area for midweek...a
refreshing respite from the oppressive air of the last week or so.
While largely dry conditions are expected...a few showers and storms
are possible focused mainly across northern counties by Thursday
afternoon as a weak front drifts into the lower Great Lakes. Highs
will mainly reside in the low to mid 80s Tuesday and Wednesday
before beginning to rise on Thursday.

Friday through Sunday...

The arrival of ridging aloft coinciding with a weakening of the
surface high will enable deeper moisture to advect back into the
Ohio Valley for late week with growing confidence in higher dewpoint
air at or above 70 degrees making a return for Independence Day into
next weekend. Instability will increase in response with isolated to
scattered pulse intensity...short lived and slow moving convection
developing during the afternoon and evening ...mainly Saturday and
Sunday. May see an increase in overall convective coverage late next
weekend into early next week with signals in the ensembles for a
cold front to approach the region from the northwest. Highs will
rise back into the lower 90s for next weekend with heat indices
again approaching 100 degrees.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 658 PM EDT Sun Jun 29 2025

Impacts:

- Convection around through much of the period, with most coverage
  early in the period and then again on Monday
- Patchy fog possible near daybreak Monday
- MVFR ceilings at times, especially late tonight and Monday morning

Discussion:

Scattered convection will diminish some this evening, but then
increase in coverage later tonight into Monday. Uncertainty remains
on how widespread the convection will be on Monday, with some hints
that most coverage won't come until later in the day into the
evening. MVFR and worse conditions are possible in convection.

Patchy MVFR ceilings will be around early, then more widespread MVFR
ceilings are expected to develop overnight and persist into Monday
morning. IFR ceilings cannot be ruled out around sunrise Monday.
Some fog is possible as well overnight.

&&

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

SHORT TERM...Ryan
LONG TERM...Ryan
AVIATION...50

Hazardous Weather Outlook
National Weather Service Indianapolis IN
322 PM EDT Sun Jun 29 2025

INZ021-028>031-035>049-051>057-060>065-067>072-301930-
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-
322 PM EDT Sun Jun 29 2025

This hazardous weather outlook is for central Indiana.

.DAY ONE...Through Tonight.

Scattered thunderstorms are expected through tonight with the
greatest coverage across the southern half of central Indiana.
Localized flooding and lightning are the primary hazards. Severe
weather is unlikely.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Greater coverage in storms expected Monday with the potential for a
few strong to severe storms. Storm chances return again by the end
of this week.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report any strong wind gusts or localized
flooding observed through Monday, though large scale spotter
activation is not anticipated.

&&

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