716
FXUS63 KIND 041507
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1007 AM EST Thu Dec 4 2025

.KEY MESSAGES...

- Patchy freezing fog and isolated light snow showers diminishing
  before daybreak today

- Wind chills of few degrees either side of zero will be possible
  across northern areas early this morning and tonight into Friday
  morning.

- Low chances for snow will be around Sunday and again Tuesday.

&&

.FORECAST UPDATE...
Issued at 1007 AM EST Thu Dec 4 2025

No significant changes made to the forecast with this update. Cold
air advection continues but is becoming less effective as winds
diminish. Temperatures have flat-lined for the most part with a
slight increase in some spots as sunshine becomes stronger. The
effect of solar insolation will be minimal, however, and highs in
the low to mid 20s are still expected.

Tonight continues to look cold, with ideal radiative cooling
potential amid a shallow to deep snowpack (deeper as one heads north
and west). Lows in the single digits or even below zero are possible
under these ideal conditions. Some lingering cloud cover may
mitigate this potential, however. Additionally, some patchy freezing
fog is possible along rivers and where cooling is most efficient.
Widespread fog potential appears low as of right now.

&&

.SHORT TERM (Today and tonight)...
Issued at 304 AM EST Thu Dec 4 2025

Current satellite and surface observations show an extensive low
stratus deck remains across central Indiana. This has kept
temperatures nearly steady overnight, but a cold front moving
through will usher in colder air later this morning. Patchy freezing
fog is also ongoing with visibilities as low as 2-4 at times. The
cold front is currently located across northwest portions of the
area and will help to clear out any fog and the stratus deck to some
degree.

Only a few locations have reported brief light snow overnight with
little to no accumulation. Latest ACARS soundings depict a lingering
pocket of dry air in the mid levels which is likely the main factor
limiting snow. Slight PBL saturation over the next few hours and
weak forcing may be enough to squeeze out isolated amounts up to a
few tenths of an inch, but the potential is low. Slick spots on
untreated surfaces cannot be ruled out due to ongoing patchy
freezing fog in addition to a low chance for very minor snow
accumulation. Any fog that develops or very light snow will diminish
before daybreak. Look for surface high pressure to build in behind
the departing cold front today. Increasing large scale subsidence
will provide quiet weather conditions across the region through
tonight.

Cold air advection should help limit diurnal heating with highs
generally ranging from the low 20s over the N/NW to near 30 degrees
across the far south. Confidence is lower than usual for lows
tonight. Surface high pressure overhead with a snowpack favors
temperatures quickly plummeting overnight, especially across the
north where there is a deeper snowpack. However, some lingering low
clouds could limit cooling. Model guidance generally suggest there
will be sufficient clearing so temperatures were lowered by several
degrees compared to NBM. Expect lows to range from the mid-upper
teens across the far south to well in the single digits over north-
central Indiana. Near zero or single digit sub-zero wind chills are
also possible over north-central Indiana.

&&

.LONG TERM (Friday through Wednesday)...
Issued at 304 AM EST Thu Dec 4 2025

Friday...

A system looks to remain south of the area on Friday, allowing quiet
weather for central Indiana. After a quite cold start, warm
advection will bring temperatures into the upper 20s to middle 30s
for highs.

Saturday...

A cold front will move through the area, but it won`t have a lot of
moisture to work with. Some guidance has been increasing the chances
for rain, but ensembles remain dry. Will continue a dry forecast.

Sunday...

Guidance continues to keep the main forcing with the low pressure
system to the south of central Indiana, and upper support isn`t
impressive. Will keep some low PoPs around.

Monday...

Cold air behind Sunday`s system will bring a potential return of
single digit low temperatures across northern areas early Monday
morning with lows in the teens elsewhere. Highs will only be in the
20s north and around 30 south. Cold temperatures will continue
Monday night with lows from 10 to 20. High pressure will keep the
weather quiet.

Tuesday and beyond...

A series of low pressure system will move through northwest flow
aloft during this period. Confidence is low in the specifics as
guidance is struggling with the strength and path of these systems.
Will continue with broadbrushed PoPs at this time, but will keep
PoPs no higher than the chance category.

If the low pressure systems track far enough north, warmer
temperatures advected into the area could bring rain as the primary
precipitation type, especially during the daylight hours.

Colder air may return Thursday behind one of the systems, but again
confidence is low.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 645 AM EST Thu Dec 4 2025

Impacts:

- IFR/MVFR cigs at IND/BMG quickly improving to VFR by 13-14Z

- Low chance for MVFR ceilings at a few sites this afternoon and
  again tonight

- Veering winds through the period

Discussion:

Conditions have quickly improved over the past few hours behind a
departing cold front. LAF/HUF have already improved to VFR with
IND/BMG expected to improve to VFR by 13-14Z. A scattered low cloud
deck around 2500-4000 feet is expected to redevelop later in the day
at most sites and persist into tonight.

MVFR conditions cannot be ruled out this afternoon with the
potential for a broken cloud deck, but confidence is not high enough
to include in the TAFS. MVFR conditions also cannot be ruled out
tonight as ceilings gradually lower with a broken cloud deck
possibly developing at some sites. Winds will weaken and veer
through the period.


&&

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

$$

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