547
FXUS63 KIND 172320
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
720 PM EDT Fri Oct 17 2025

.KEY MESSAGES...

- Rain and thunderstorms expected late Saturday into Sunday along
  with occasional wind gusts of 30-40 mph.

- Isolated strong to severe wind gusts possible Saturday night

- Turning cooler following frontal passage Sunday and Monday

&&

.SHORT TERM (This evening through Saturday night)...
Issued at 231 PM EDT Fri Oct 17 2025

Through Tonight...

Quiet conditions will continue through tonight. The upper ridge will
exit off to the east, and a weak upper wave will move through.
However, only mid and high level moisture is available. The result
will be partly to mostly cloudy skies. Lows will be in the middle
and upper 50s.

Saturday...

The morning will be quiet as a system approaches from the west.
Winds will turn southwest and begin to bring moisture into the area.
Clouds will increase.

During the afternoon, an initial surface trough and initial round of
upper energy will generate an area of showers and thunderstorms.

A fair amount of uncertainty remains on how far southeast decent
forcing will actually make it. For now it looks like enough forcing
should reach up to the northwest half or of the area to go with
likely and higher PoPs. The southeast half will see weaker forcing
and only chance PoPs.

Some gusty winds are possible with storms that do develop, along
with locally heavy rain.

Depending on the thickness of the clouds and arrival time of rain,
near record high temperatures are possible. Indy`s record high is 84
(1953), and highs around 80 look reasonable there. Farther
southeast, highs in the lower 80s are expected.

Saturday night...

An upper level jet will strengthen the upper trough as it moves
toward the area. At the surface, a low will deepen as it moves
northeast. The path of the surface low will be northwest of the
area. 850mb winds will increase to around 50kt.

Integrated vapor transport forecasts show strong moisture transport
into the area. The strengthening system will have plentiful forcing.
These will lead to widespread rain, so will go high PoPs all areas.

As the surface cold front moves in late evening/overnight, the setup
will be a low CAPE/higher shear situation. If the line of storms
ahead of the cold front becomes/remains organized, locally severe
winds are possible, along with isolated tornadoes from mesovorticies
in a QLCS. However, confidence that everything will line up properly
isn`t high. Will continue to mention an isolated severe storm chance.

Larger scale models have been trending northwest for the axis of
heavy rain, with only the far northwest forecast area having the
higher rainfall totals. The NAM is farther southeast. HREF
Probability Matched Means show the possibility of localized amounts
over 2 inches in portions of the western forecast area.  The good
moisture transport and some frontogenetical forcing definitely give
the possibility of locally heavy rain.

The dry ground can take a lot of rain, especially northwest. Even
so, the threat for isolated flooding cannot be ruled out. Will
continue to monitor trends and refine as necessary.

With the strengthening low and decent winds aloft, some gusty winds
may occur even outside of storms.

&&

.LONG TERM (Sunday through Friday)...
Issued at 231 PM EDT Fri Oct 17 2025

Sunday...

The upper trough axis will cross the area Sunday, ending the rain as
it does. A tight pressure gradient will continue across the area as
the strong surface low exits to the north, and stronger winds will
remain aloft. These conditions will allow for wind gusts in the 30
to 40 mph range during the day Sunday.

Temperatures will remain cool with the lingering clouds/rain, with
readings around 50 degrees. As the rain ends and clouds diminish,
readings will rebound to around 60 most areas.

Monday and beyond...

A couple of upper systems will move through the area during this
period. The stronger forcing from these look to remain north of the
area, and moisture isn`t impressive. Will this go only chance or
lower PoPs around Monday night and again around Thursday. Specific
timing will become clearer with later guidance.

With the systems moving through, winds will be more active with some
gusts around 25 mph possible at times.

Temperatures will be much more seasonable with highs in the 50s and
60s and lows in the upper 30s into the 40s.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 719 PM EDT Fri Oct 17 2025

Impacts:

- Wind gusts 15-25KT after 15Z Saturday...and to 18-27KT late day
- Low chance of convection after 18Z Saturday...greater chances
  after 00Z Sunday
- MVFR/worse possible after 03Z Sunday at KIND

Discussion:

VFR conditions will continue over central Indiana terminals through
at least midday Saturday...and likely into Saturday evening...ahead
of deteriorating conditions later Saturday night.  Deepening surface
low pressure tracking from Oklahoma tonight to Chicagoland by the
end of the TAF period...will veer surface flow from SSE to S
tonight... and increase SSW sustained winds Saturday from 8-10KT at
14Z, to 10-15KT by 18Z.  Gusts up to 18-26KT are expected within 18-
23Z.

Thick mid/high cloud this evening should scatter out from west to
east after 03Z tonight, with perhaps FEW at KIND/KBMG at dawn
Saturday.  Decks to increase/thicken from NW to SE Saturday
morning...with mid cloud ceilings the rule after 18Z.  Expect at
least a few -SHRA and possible isolated TSRA after 18Z, especially
near KLAF.  Steadier SHRA to advance into KIND after 00Z Sunday.

&&

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

$$

SHORT TERM...50
LONG TERM...50
AVIATION...AGM