407
FXUS63 KIND 031752
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1252 PM EST Wed Dec 3 2025

.KEY MESSAGES...

- Freezing fog possible through mid-morning

- Light snow likely tonight, minor accumulations possible before
  Thursday morning commute

- Wind chills of few degrees either side of zero will be across
  northern areas early Thursday and again Thursday night/early
  Friday.

- Accumulating snow is possible Sunday and again next Tuesday.

&&

.FORECAST UPDATE...
Issued at 919 AM EST Wed Dec 3 2025

No significant changes made to the forecast this morning. We did add
the mention of flurries around the Indy metro area. Radar and
observations show this activity, likely originating from ground
sources seeding the low-stratus layer above. Overall, activity has
been diminishing.

We`ve deviated from guidance regarding sky cover as the
aforementioned low stratus remains locked in over most of central
Indiana. These stable cloud layers can be quite hard to scour out,
and we`ve retained 90-100 percent sky cover longer than guidance
shows. This cloud deck is still expected to break up today as winds
increase from the south, though this will take some time.

Mid to high-level clouds are already on the way ahead of a cold
front expected to arrive tonight. Even with the low stratus
diminishing, skies are still expected to remain BKN to OVC for most.

We`ve nudged high temps downward a bit to adjust for the lingering
low clouds.

&&

.SHORT TERM (Today and tonight)...
Issued at 302 AM EST Wed Dec 3 2025

Current satellite and surface observations show a persistent stratus
still in place across central Indiana. Fog has gradually developed
across portions of central Indiana as strengthening southwesterly
flow promotes modest warm air advection over a healthy early
December snow pack. Expect fog to continue gradually expanding in
coverage towards daybreak. Any fog that develops should then clear
out through the morning due to slight surface heating.

Quiet weather conditions are expected today with surface high
pressure across the region. Forecast soundings depict a subsidence
inversion and dry column through the day. The inversion may make it
difficult for clouds to clear out, but at least some diurnal mixing
should help promote gradual clearing, predominately over south-
central IN. Limited daytime heating due to low clouds is expected to
keep highs in the low-mid 30s this afternoon. Some locations may
struggle to get out of the upper 20s.

A shortwave trough will push a strong cold front through the region
tonight. Forecast soundings depict the aforementioned subsidence
induced dry air aloft quickly saturating during the evening thanks
to moisture advection, weak forcing, and evaporative cooling. A
brief period of light snow is likely this evening and into the
overnight once this occurs. A lack of deeper moisture return will
keep snowfall amounts very light, generally ranging from a trace to
half an inch. Locally higher amounts up to an inch are possible.

Temperatures tonight will differ significantly from NW to SE. A
colder airmass filtering in behind the front is expected drop
temperatures into the single digits across northwest portions of
central Indiana. Meanwhile, lingering clouds and possibly some light
snow over far southeastern counties late tonight should help keep
temperatures warmer in the low 20s.

&&

.LONG TERM (Thursday through Tuesday)...
Issued at 302 AM EST Wed Dec 3 2025

Thursday...

Drier air moving in with high pressure will allow skies to become
clear to partly cloudy. Some lower clouds may linger in the
northeast with some lake effect clouds influencing the area. Strong
cold advection will only allow temperatures to rebound to the middle
teens northwest to the upper 20s southeast.

Fewer clouds to start Thursday night along with the snow cover will
allow temperatures to drop quickly, with readings falling in the
single digits across much of the northern and west central forecast
area. The far northwest area may see below zero numbers. Readings
will steady out or rebound overnight with additional clouds moving
in.

Friday and Saturday...

On Friday, a southern stream system should remain far enough south
as to not influence the area. Guidance that shows precipitation
reaching the southern forecast area looks overdone.

A weak cold front will move in Saturday, but with a lack of forcing,
will keep the forecast dry.

Below normal temperatures will continue.

Sunday and Sunday night...

An upper trough and a surface low pressure system will bring a
chance for precipitation to the area during this time. Uncertainty
remains though on the timing and the path of the area of low
pressure, which looks to remain south. Chances of precipitation will
determine on how far south it goes. Will keep some chance PoPs
around.

Precipitation type will depend on how warm it gets, but for now it
looks like rain or mix of rain and snow south with snow north, with
mainly snow during Sunday night.

Monday and beyond...

A series of upper impulses and surface fronts will move through
northwest flow aloft. These will bring occasional chances for
precipitation, but timing of the greatest chances remains uncertain.
Will broadbrush chance PoPs for much of the period, mainly Tuesday
onward.

Precipitation type will once again depend on how warm it gets.
Models are trying to warm things up enough by Wednesday so that rain
becomes the primary type, but confidence is low at this stage.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 1252 PM EST Wed Dec 3 2025

Impacts:

- IFR ceilings continue this afternoon, possibly into this evening.

- Light snow after 00z, ending before 09z.

- Cold front passage tonight, wind shift from WSW to NNW

Discussion:

IFR stratus continues across central Indiana, and has been difficult
to dislodge today despite southerly winds of 10-15kt. IFR ceilings
may disperse a bit into a SCT/BKN layer as a surface cold front
approaches this evening. Should clearing occur, some patchy fog may
develop across portions of Indiana shortly after sunset.

Light snow associated with the front is becoming increasingly likely
beginning just after 00z. Though light, brief reduction to IFR
visibility is possible at times.

The cold front itself arrives from the northwest around 02z-03z at
LAF, reaching BMG by 04z-06z. An abrupt wind shift from WSW to NNW
is expected, with speeds increasing to 10-15kt, diminishing after
12z.

MVFR ceilings may linger well into the day Friday behind the front,
though some improvement is likely towards the end of the TAF period.

&&

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

$$

UPDATE...Eckhoff
SHORT TERM...Melo
LONG TERM...50
AVIATION...Eckhoff