456
FXUS63 KIND 011402
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1002 AM EDT Sat Aug 1 2026

.KEY MESSAGES...

- Showers Expected today; Isolated thunderstorms possible.

- Rain chances will persist through the weekend. Heavy Rain
resulting in flash flooding cannot be ruled out Saturday afternoon
and evening

- Additional rain chances possible at times next week

&&

.FORECAST UPDATE...
Issued at 958 AM EDT Sat Aug 1 2026

Current KIND radar imagery depicts a large area of clearing across
central Indiana with a band of light to moderate rain over far
east/northeastern counties. Look for the band of rain to continue
pivoting northeastward as the associated lead impulse aloft departs.
The main vort max remains further west across Illinois at this time
which continues to slowly push southeastward. Increasing large scale
ascent from the approaching mid-upper level vort max combined with
low-level theta-e advection ahead of an associated low pressure
system will promote additional convective development after a brief
lull. Look for widespread showers and scattered thunderstorms by
this afternoon.

Efficient rainfall rates and repeated rounds of showers/storms this
afternoon through tonight could result in localized flash flooding.
An associated warm front lifting north is expected to stall near or
just north of the I-70 corridor into the evening hours which may
also increase the threat for flooding as slow moving storms could
train over the same areas.

Moderate destabilization by the afternoon hours combined with
sufficient effective wind shear supports the threat for isolated
severe thunderstorms, mainly for E/SE portions of central Indiana.
Forecast soundings depict gradually steepening lapse rates and
mid- level dry air contributing to DCAPE values up to 1000 to 1100
J/KG which may result in isolated damaging wind gusts. Low-level
veering hodographs from the warm front lifting north this morning
into the afternoon could also promote an isolated tornado threat.

Some uncertainty remains regarding the overall severe threat.
Mesoscale details such as how far north the warm front moves and the
degree of low-level buoyancy later this afternoon will ultimately
determine the severe weather risk. Stay tuned for updates as these
details become clearer. The flash flooding threat remains the
greatest concern today, but isolated severe weather remains possible
over mainly E/SE portions of central Indiana.

&&

.DISCUSSION (Today through Friday)...
Issued at 249 AM EDT Sat Aug 1 2026

Surface analysis early this morning shows low pressure in place over
western IL. The low was beginning to push toward Central Indiana,
providing cyclonic flow across the area. Radar shows a wave of
showers over Illinois, poised to push in to western Central Indiana.
Aloft, water vapor imagery showed an upper low over IA and MO,
pushing east toward Indiana. strong ridging was found over the
western CONUS while weaker ridging was found over the east coast.
These ridges will lead to the eventual cutoff of the low. Moisture
was plentiful across across Indiana with dew points in the upper 60s.

Today...

Models show the low pressure system pushing into SW Indiana today,
with continued broad cyclonic flow across our state.  Forecast
soundings shows deep saturation with pwats as high at 1.9 inches
this afternoon. CAPE and instability appear minimal. HRRR does not
show a shield of rain arriving, but rather spokes or waves passing
across the forecast area from time to time. Thus confidence for rain
will be high today, but precipitation is more likely to be on and
off through the day as these spokes pivot. High pops will be used.
Given the expected clouds and rain, highs will struggle to reach the
mid 70s.

Tonight through Monday...

Little overall change is expected the weather tonight through Sunday
Night. The upper low is expected to be cut off from the main flow
and stall over SE IND and KY. This will place our area on the north
side of the low where low cigs and cyclonic flow and light rain and
drizzle will be present, especially tonight. Again on Sunday,
instability appears limited with little to no CAPE available but
high pwats remain. Thus again, confidence is high for continued on
and off showers through at least Sunday Night.

On Monday, rain chances will persist although forecast soundings
begin to dry out top down. The low, positioned to the southeast,
will allow a cooler and drier flow of air on NE winds. Lower levels
remain saturated amid cyclonic flow. Thus the heavier rain threat
should be diminished by this point but very light rain showers will
remain possible.

Clouds and rain through the period will limit daytime heating,
allowing for highs mainly the 70s, while low remain in the mid to
upper 60s.

Tuesday through Friday...

An active weather pattern is expected for much of the work week
ahead. Models suggest the lingering cut off low will finally exit on
Tuesday as a weak trough and sag within the upper flow across the
CONUS. This will result in a shallow trough aloft over Indiana
during this period. This quick flow aloft, across the northern CONUS
will bring several embedded short waves across Indiana through the
work week providing chances for precipitation. With the lower
levels, weak high pressure is suggested to to be moving through the
Great Lakes and northern Central Indiana on Tuesday into Wednesday.
The northeasterly surface flow may limit rain chances somewhat on
Tuesday and Wednesday, but still some weak forcing will be passing
with dew points in the 60s. Forecast soundings at these times show
mainly a dry column.

Higher confidence for rain will be on Thursday and Friday as the
high drifts to the east which will open up warm and more humid south
and southwest flow. This in combination with the forcing passing
aloft will necessitate daily chances on Thursday and Friday.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 631 AM EDT Sat Aug 1 2026

Impacts:

- Mainly MVFR Cigs deteriorating to IFR through this TAF period.

- Periods of SHRA at times through the period, with isolated TSRA
  possible.

Discussion:

Low Pressure over Illinois will advance to Indiana during this
period, Spokes of showers pivoting around the low are expected to
pass through the day. CIGS in the wake of the the first band of
showers have fallen to MVFR and more IFR conditions are found
upstream. These are expected to arrive tonight as the upper low
resides in SW Indiana. Confidence for precise timing of any wave of
rain is low. Thus will handle precip mentions with large windows of
VCSH and focus on short term updates with prevailing mentions when
confidence is higher.

Isolated TSRA will be possible, but instability appears limited.
Thus will leave this mention out for now.


&&

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

$$

UPDATE...Melo
AVIATION...Puma
DISCUSSION...Puma