187
FXUS63 KIND 050343
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1143 PM EDT Sat Oct 4 2025

.KEY MESSAGES...

- Very warm again on Sunday.

- Next best chance for rain is late Monday night through Tuesday
  night.

- Dry weather with seasonable temperatures return for Wednesday
  through Friday

&&

.FORECAST UPDATE...
Issued at 903 PM EDT Sat Oct 4 2025

Clear skies and light S/SE winds making for a pleasant evening
across central Indiana. 01Z temperatures ranged from the mid 60s to
the mid 70s.

The forecast is in excellent shape for the overnight as the Ohio
Valley remains under a strong surface ridge with broad subsidence.
The airmass is drier tonight with little if any fog anticipated
towards daybreak Sunday. Lows will fall into the mid and upper 50s
over much of the forecast area.

Zone and grid updates out.

&&

.SHORT TERM (This evening through Sunday)...
Issued at 203 PM EDT Sat Oct 4 2025

Rest of This Afternoon...

Heating and some low to mid level moisture has led to a cumulus
field across central Indiana early this afternoon. There is some
weak mixed-layer CAPE across the northern forecast area, and
satellite shows some towering cumulus.

However, there is a weak inversion aloft which should help keep a
lid on things this afternoon. A rogue shower cannot be ruled out,
mainly north, but odds are too low to mention.

Otherwise, very warm conditions will continue with generally light
southwest winds.

Tonight...

The cumulus field will dissipate with loss of heating, leaving clear
to mostly clear skies. With light winds and mostly clear skies
expected, some ground fog may develop. Impact of this is not
expected to be enough to put in the forecast.

Lows will be in the mid 50s to around 60.

Sunday...

Influence from upper and surface highs will keep quiet weather
across central Indiana. Some cumulus may pop up again.

With no real change in airmass, will go a bit higher than guidance
and keep highs in the middle 80s most areas. At Indianapolis, the
record high for Sunday is 87, set in 2007.

&&

.LONG TERM (Sunday night through Saturday)...
Issued at 203 PM EDT Sat Oct 4 2025

Sunday night through Tuesday night...

A weakening upper wave along with moisture from the Gulf will
approach the area Sunday night and then move in on Monday.
Forcing/moisture look to remain out of the area Sunday night, so
will keep a dry forecast then.

Meanwhile, a surface cold front will approach central Indiana Monday
and move in for Monday night into Tuesday.

Forcing should be low enough during the day Monday for only some
chance PoPs, with the highest PoPs in the afternoon when better
instability will exist. The relatively slow moving cold front will
interact with the Gulf moisture and should produce more widespread
rain Monday night into Tuesday. Will go likely or higher PoPs most
areas at some point during those periods.

However, will have to watch this because the NAM wants to keep the
slug of moisture farther south and east, which would lower PoPs over
central Indiana.

It will take another upper wave from the northwest moving through to
finally kick the surface front southeast of the area, so will keep
some PoPs going through Tuesday night.

Temperatures will remain warm on Monday and in the 80s. Exactly how
high they get will depend on the cloud cover from the southern
moisture. Tuesday will be cooler with the front and rain in the area.

Wednesday through Saturday...

Some brief upper ridging will build in by Thursday along with
surface high pressure. This will provide dry and much cooler
conditions to the area, with highs in the 60s and 70s and low in the
40s.

Questions remain on the strength and timing of an upper trough
around Friday along with the amount of moisture available to the
system. At the surface, a cold front will move into the area. For
now, will just keep some low PoPs around on Friday night with low
confidence.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1142 PM EDT Sat Oct 4 2025

Impacts:

- None; Mainly VFR conditions are expected.

Discussion:

Mainly VFR conditions are expected throughout the period...but
ground fog cannot be ruled out near sunrise at all but KIND.

Strong high pressure east of the middle Atlantic States along with a
westward extending surface ridge to KY and MO was continuing to
control the weather across Central Indiana. GOES19 shows clear skies
across the state.

The high will maintain control over the TAF sites through Sunday
along with subsidence in place aloft. A few diurnal cu will be
possible this afternoon, but forecast soundings again depict a mid
level inversion that should prevent deep vertical growth. Southerly
winds will increase in response to a tightening surface pressure
gradient...with the potential for periodic gusts to around 20kts in
the afternoon at KHUF and KLAF.

High clouds will begin to invade after 060600Z as an upper trough
approaches from the northwest, along with an upper disturbance from
the south.

&&

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

$$

UPDATE...Ryan
SHORT TERM...50
LONG TERM...50
AVIATION...Puma