334
FXUS63 KIND 071916
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
216 PM EST Fri Nov 7 2025

.KEY MESSAGES...

- Wind gusts to 30 mph through sunset

- Rain likely Saturday night into Sunday

- Turning colder with a chance of snow showers Sunday afternoon into
  Monday morning

- Lows in the 20s Sunday night and Monday night, with wind chills
  in the teens at times Sunday night into Monday night

&&

.SHORT TERM (This evening through Saturday)...
Issued at 216 PM EST Fri Nov 7 2025

Rest of Today and Tonight.

Clouds continue to quickly clear across the state with much of
Illinois and northwestern Indiana already showing clear skies.
Showers have exited the state with wind gusts gradually ramping up
as skies clear and temperatures rise into the low to mid 60s. Winds
at the top of the boundary layer are 30-35kts which will allow for
the wind gusts to become more frequent through the afternoon as
mixing becomes more efficient. As the surface inversion settles in
after sunset, the boundary layer will decouple and winds will drop
closer to calm through the night, especially as the pressure
gradients continue to settle.

There may be a few areas of shallow ground fog towards daybreak,
especially in valleys and other favored fog formation zones as the
winds calm and skies remain clear. Overnight lows will bottom out in
the upper 30s to near 40 under the calm skies, but that will be
dependent on the drop of dew points as drier air works into the area.

Saturday.

Clouds will gradually work back into the area during the day
tomorrow ahead of the next and stronger system which will create a
fairly significant temperature gradient across the state with mid 60s
near the Ohio River and mid 40s near the Michigan border.
Precipitation may arriving in the far northwestern counties during
the evening hours, but this is expected to generally occur towards
the overnight which will be discussed in the long term section below.

&&

.LONG TERM (Saturday night through Friday)...
Issued at 216 PM EST Fri Nov 7 2025

Our primary forecast challenge in the long range is the chance of
snow and cold temperatures this weekend into next week. Synoptic
analysis shows a progressive quasi-zonal jet across the CONUS. A
recent storm track to our north has keep temperatures above normal
for the most part. Going forward, guidance is in very good agreement
showing strong ridge-building over the West Coast. This in turn
causes the flow pattern over the CONUS to become highly amplified.
Deep troughing is shown to develop over the eastern US by Sunday.

Scaling downward, a vort max currently over the Pacific Northwest
drops southeastward as we head into the weekend. This clipper-like
system should begin to gain a neutral to negative tilt as is enters
the Midwest, increasing overall large-scale lift. Surface
cyclogenesis should commence to our west with the resulting low
passing directly over central Indiana or just to our north. The
exact track will determine who sees the most precipitation Saturday
night into Sunday. Overall guidance is in fairly good agreement with
the position and track of the low but a little more uncertain on its
intensity.

Most guidance depicts an extensive precip shield developing on the
northeast flank of the approaching low, primarily along the warm
front / region of isentropic lift. Jet dynamics and mid-level
frontogenesis favor these areas as well but also a bit further south
near the system`s center. Though northern Indiana is favored for the
broad area of stratiform precipitation, central Indiana may
experience a more scattered / convective precip situation.
Temperature profiles support rain for the entirety of our CWA as the
system passes through. Snow does not appear likely until after the
system is to our east, with winds becoming northerly and strong cold
air advection taking hold. Most rain associated with the low will
end by sunrise Sunday. Total rainfall is expected to be light, for
the most part, with high end amounts between 0.25 and 0.50". The
best chance of higher rainfall totals is across the northern half of
our CWA.

Temperatures...

A secondary trough / vort max is modeled to drop south behind
Sunday`s system. Ensemble 850mb temperatures as low as -10C to -15C
are shown, corresponding to surface temperatures well into the 20s
(F). Radiative cooling potential does not look to be ideal, at least
Sunday night into Monday. A strong MSLP gradient should lead to
breezy conditions through Monday. Though this may keep surface
temperatures from falling as low as they potentially could. However,
it may also help it `feel` much colder due to low wind chills. Wind
chill values well into the teens (F) are not out of the question
Monday morning. Radiative cooling potential is better Monday night
into Tuesday morning, but by this point the trough is already moving
out with warm air advection returning. Still, lows well into the 20s
are likely.

Snowfall Potential...

As the secondary trough drops southward on Sunday, very cold air
aloft will move over Lake Michigan which is still quite warm. This
setup should destabilize the air mass as it heads south. Combined
with some positive vorticity advection aloft and cyclonic surface
flow, scattered to numerous snow showers are becoming likely Sunday
into Monday. These snow showers may organize into a broken band
extending south from Lake Michigan, gradually shifting eastward as
the wind direction become more westerly with time.

Amounts are uncertain as of right now, due to the expected scattered
nature of the snow showers. Given the dependency on lake-generated
instability, the best chance of snow and of accumulations would be
across our north and northeastern counties. Most guidance depicts
fairly light amounts generally under an inch. Should snow
accumulations occur, they will primarily be on elevated and grassy
surfaces.

Tuesday Onward...

Deep troughing departs quickly on Tuesday with warm air advection
resuming. Temperatures trending back towards normal (55/37) as early
as Wednesday are expected. Quiet and dry weather are likely through
most of next week as well.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 1153 AM EST Fri Nov 7 2025

Impacts:

- MVFR cigs through 21Z
- Southwesterly wind gusts to 25kts through 01Z
- Brief MVFR to IFR vsbys 12Z to 14Z, best chances at LAF and BMG

Discussion:

Skies will gradually clear through the remainder of the afternoon
with VFR conditions expected towards 21Z. As the skies clear,
southwesterly to westerly wind gusts to 25kts will become more
frequent, especially at LAF and IND. Clouds will then remain limited
to just high clouds through the overnight with shallow fog possible
towards daybreak tomorrow.


&&

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

$$

SHORT TERM...White
LONG TERM...Eckhoff
AVIATION...White