921
FXUS63 KIND 260656
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
256 AM EDT Sat Jul 26 2025

.KEY MESSAGES...

- Heat Advisory across portions of central and southern Indiana
  through tomorrow evening

- Dangerous heat continues into early next week with additional days
  of greater than 100 degree heat indices likely

- Periodic showers and storms through the weekend with isolated
  flooding and strong winds

&&

.SHORT TERM (Today and tonight)...
Issued at 255 AM EDT Sat Jul 26 2025

Surface analysis early this morning shows a poorly defined frontal
boundary draped from Central IL northeast to northern Indiana and
MI. Convection over IL was present near this boundary and was
pushing northeast along it. High pressure was found north of the
boundary over Ontario and a second area of high pressure was found
over the southeastern states. The southern high was resulting in a
continued lower level flow of hot and very humid gulf air streaming
into the Ohio Valley. Aloft, water vapor imagery shows a plume of
tropical moisture streaming across TX, northward to IA and MO, and
then northeast to IL, NRN Indiana and MI. the ongoing storms were
staying confined mainly to underneath this plume. An upper level
high pressure system was found over the SE states, resulting in ring
of fire like effects over IL into northern Indiana.

Today...

Little overall change will be expected today across Central Indiana.
The very hot and humid air mass in place across the area will
continue to control our weather as the upper high is suggested to
strengthen and steer potential forcing dynamics and the tropical
plume farther to the north. Forecast soundings once again show a
favorable signature for diurnal convection with steep lapse rates
and CAPE values over 2800 J/KG. Pwats also are favorable with values
in excess of 1.90 inches. HRRR also suggests afternoon shower and
storm development due to these favorable conditions. Thus will once
again include afternoon pops for hit and miss diurnal storms. Heavy
rain will be possible considering the very moist air mass. HRRR
suggests storms dissipating by early evening.

Again high dew points in combination with highs around 90 will
result in heat index values in the low 100s. Ongoing Advisory will
remain.

Tonight...

A few lingering diurnal storms will be possible in the evening
before the rest of the evening looks to remain mostly dry. Models
suggest an organized area of convection and forcing well to the
north of Central Indiana, over northern Indiana and Michigan during
the evening, However, the tail of this system may trigger some
overnight convection across Central Indiana. Confidence for this is
low, but given our continued warm and humid air mass, small chances
for pops will still be necessary for now. Lows overnight will
remain warm and humid, in the middle 70s.

&&

.LONG TERM (Sunday through Friday)...
Issued at 255 AM EDT Sat Jul 26 2025

For much of the long term, central Indiana will sit between an upper
high meandering over the SE states into the central plains and a
large upper low over Canada. This will place the area in a hot and
humid pattern with almost daily chances for showers and storms.
Severe weather looks unlikely with a lack of shear, but can`t rule
out an isolated downburst causing damaging winds. Highs through
midweek are expected to range from the upper 80s to low 90s. With
ample humidity to continue, heat headlines will likely continue as
heat indices near 100-110 will be probable.

By mid to late next week, the upper low over Canada will dip
southward, bringing cooler and drier air to the region. Highs for
late week into the weekend may even max out in the upper 70s for a
day or two, providing a relief to the heat.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1252 AM EDT Sat Jul 26 2025

Impacts:

- High VFR Cigs overnight at LAF, HUF and IND
- Scattered convection developing again Saturday afternoon

Discussion:

Convection developing over IL will result in CI blow off
overnight providing high CI cigs at LAF, HUF and  perhaps BMG. The
convection is expected to push northeast during the overnight hours,
remaining north of all of the TAF sites. A stray, isolated TSRA will
be possible in the very warm and humid air mass in place, but
confidence is too low to be worthy of a mention.

The very warm and humid air mass will remain over Central Indiana
today, and once again forecast soundings are favorable for diurnal
convection. HRRR suggests isolated shower and storm coverage this
afternoon as highs in lower 90s are reached. Confidence for specific
timing or locations of any storms is small, so just a period of VCTS
has been used for now during the most favorable hours for storms.

Any TSRA that strikes a TAF site may result in brief MVFR to IFR
conditions.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM EDT this evening for INZ043>047-051>057-
060>065-067>072.

&&

$$

SHORT TERM...Puma
LONG TERM...KF
AVIATION...Puma