347
FXUS63 KIND 131617
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1217 PM EDT Mon Oct 13 2025

.KEY MESSAGES...

- Dry weather through Friday with warmer than normal temperatures
  continuing

- Rain chances return Friday night into the weekend

- Cooler temperatures arrive Sunday

&&

.FORECAST UPDATE...
Issued at 926 AM EDT Mon Oct 13 2025

Sunny start to the morning as most of the localized fog had already
diminished. 13Z temperatures were generally from the upper 40s to
mid 50s.

Another warm and quiet day in store for the region with ridging
aloft and at the surface in control over the Ohio Valley. A
weakening frontal boundary was currently located from the western
Great Lakes southwest into Missouri. The front will largely diminish
as it runs into the upper ridge axis overhead but do anticipate some
of the mid clouds associated with the boundary to overspread the
northwest half of the forecast area through the day. Even with the
clouds...low level thermals support a warm afternoon with highs in
the mid and upper 70s.

Zone and grid updates out.

&&

.SHORT TERM (Today and tonight)...
Issued at 231 AM EDT Mon Oct 13 2025

Today.

Quiet conditions are expected through the remainder of the overnight
with no impactful weather outside of patchy fog towards daybreak.
Winds have have dropped to near calm over the last hour with dew
point depressions gradually decreasing in nearly ideal
radiational cooling conditions. Towards daybreak expect to see at
least some shallow field fog and localized fog along streams. This
fog will quickly erode by around 9AM as the dew point depressions
begin to increase.

Expect to see another mild day today with cloud cover gradually
increasing through the day as the mid and upper levels saturate
due to moisture advecting in from the west. The more widespread
cloud cover will remain in Illinois, but expect at least some
cirrus aloft. Temperatures today will end up a bit warmer than
previous days with highs in the mid to upper 70s. Diurnal cu
coverage will again be minimal with saturation at the top of the
boundary layer not expected.

Tonight.

Milder temperatures are expected tonight, especially across the
western counties where mid and high level cloud coverage will be
highest. Expect to see lows ranging from the upper 40s in the east
to the mid 50s in the west. Skies across the east will be clear to
mostly clear which may allow for some patchy fog again towards
daybreak, but think that the better chances and greater coverage
will be further east into Ohio.

&&

.LONG TERM (Tuesday through Sunday)...
Issued at 231 AM EDT Mon Oct 13 2025

Tuesday through Friday...

Dry and warm weather is expected to continue through the work week.
Models show strong upper ridging settling over the Mississippi
Valley on Tuesday before reorganizing and strengthening on Wednesday
through Friday. By Thursday night and Friday this ridge axis is
expected to be over Indiana. This is a favorable pattern for
subsidence and drying. Little in the way of forcing dynamics appear
to be present as this feature passes. Within the lower levels, a
very large area of high pressure is suggested to develop, engulfing
the Great Lakes, the Ohio Valley and the Gulf Coast. This large high
will pass across Central Indiana on Wednesday through Thursday,
providing more dry but warm fall weather. Other than Tuesday, when
highs will reach the upper 70s,  Temperatures should slowly moderate
as the week progresses, with highs again reaching the middle and
upper 70s by Friday. High temperatures for much of the week look to
be 7-13 degrees above normal.

Friday night through Saturday...

Models show that as the ridge axis departs to the east on Friday,
southwest flow aloft becomes present over Central Indiana. Within
this southeast flow aloft, a wave of forcing ahead of an approaching
surface cold front is suggested to push across Central Indiana on
Friday Night and into Saturday. At this time ample moisture within
the mid levels appears to be present on Friday Night. Thus this may
be our next best chance for rainfall across Central Indiana. Will
use the higher pops at that time as these features appear available.
Precipitation chances should linger on Saturday as the surface front
is shown to slowly pass. Forecast sounding again here show plentiful
moisture available, so again, pops still will be needed at this time.

Sunday...

In the wake of the front on Sunday, strong subsidence and drying is
shown to continue. This will be associated with the expected arrival
of high pressure. Will trend toward a dry forecast at that time with
more seasonable temperatures.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 1217 PM EDT Mon Oct 13 2025

Impacts:

- None

Discussion:

Mid and high level clouds associated with a weakening frontal
boundary over Illinois will drift into parts of the region through
the afternoon but expect skies to revert back to mainly clear skies
tonight as the boundary washes out. Model soundings show slightly
better boundary layer moisture present on Tuesday which may be
enough to generate few to scattered cu by midday. Light E/NE winds
will continue through late Tuesday.

&&

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

&&

$$

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