314
FXUS63 KIND 222300
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
600 PM EST Thu Jan 22 2026

.KEY MESSAGES...

- A COLD WEATHER ADVISORY is in effect along and north of a Terre
  Haute to Muncie Line from 1AM Friday through 10AM EST Saturday.

- Near zero or Subzero lows possible Thursday and Friday nights
  along with potentially dangerous wind chills at or below -10F.

- Winter Storm Watch for all of central IN Sat-Sun with potential
  for significant accumulating snow and travel impacts

- Very cold temperatures persist into next week with potentially
  dangerous wind chills possible at times.

&&

.SHORT TERM (This evening through Friday)...
Issued at 312 PM EST Thu Jan 22 2026

Deep troughing and an associated polar low are passing to our north
this afternoon. A cold front extending southwestward from the low
will drop southward tonight. A strong 1050 mb high pressure system
likewise drops southward into the northern Plains behind the
departing front. A very cold Arctic air mass is moving in tandem
with this high pressure system, and some of the coldest air of the
season arrives tonight.

The front arrives around midnight tonight, with brisk northwesterly
winds between 10-15 mph gusting to 25 mph. Temperatures are modeled
to fall quickly into the teens and single digits, potentially as low
as 0 degrees by tomorrow morning (especially further northwest).
Combined with the winds, apparent temperatures as low as -10 to -20
will be common. High temperatures are not expected to recover much,
if at all. Single digit highs are possible throughout much of the
CWA tomorrow. A Cold Weather Advisory is in effect tonight through
early Saturday.

Guidance is in good agreement depicting the Arctic high weakening
and quickly translating eastward as a trough digs into the
southwestern US. Surface winds subsequently diminish a bit and
become northeasterly. Cloud cover increases substantially Friday
night as the trough develops to our west. Despite thickening cloud
cover, continued (but weaker) cold air advection should allow for
another night with lows near 0 degrees.

The trough mentioned above is the system expected to bring impactful
winter weather to much of the CONUS, including Indiana. See the Long
Term section below for details.

&&

.LONG TERM (Friday night through Thursday)...
Issued at 312 PM EST Thu Jan 22 2026

Friday night Through Sunday.

The primary focus of the long term period remains a potent and
highly impactful winter storm system slated to traverse the region
this weekend. Ensemble guidance continues to coalesce around a
solution that brings a deep, moisture-rich plume of Gulf air into
contact with an entrenched, brutally cold Arctic airmass. While the
exact track of the surface low remains subject to minor shifts, the
overall synoptic setup, featuring a strong high pressure center to
the north and a sharpening baroclinic zone favors a significant
winter weather event for much of the Ohio Valley.

Confidence continues to increase in a widespread snowfall event,
particularly for areas near or south of I-70 even as there remains
some questions on overall totals.  Latest ensemble and deterministic
guidance has trended further north today. Ensemble means still
suggest the highest probabilities for greater than 5-8 inches of
snow reside across the southern portions of the forecast area, where
the best overlap of frontogenetical forcing and deep moisture
resides. Confidence is also increasing for higher snowfall amounts
to the north, but uncertainty remains due to the antecedent dry air
in place from the Arctic high to the northwest.

After collaboration with neighbors, we have gone ahead and issued a
Winter Storm Watch for all of central Indiana given latest model
trends. Confidence is highest in at least 5+ inches of snow near and
south of the I-70 corridor with the thought that the far
north/northwest portion of the Watch may end up in an Advisory while
areas further south end up in a Warning. This gives us the
flexibility to continue to monitor forecast trends and adjust
accordingly.

Where we have higher confidence is in very cold temperatures through
the duration of this event, with highs on Saturday and Sunday
struggling to reach the mid-teens and overnight lows plummeting into
the single digits to potentially below zero. This will create a very
deep DGZ. Because of the sub-freezing depth of the airmass, SLRs are
expected to be well above the climatological 10:1 average. We are
currently forecasting ratios in the 12:1 to 18:1 range, meaning
even modest amounts of liquid equivalent could lead to
accumulations and rapid reductions in visibility.

All that being said, there remains a potential failure mode for the
system as the surface low and associated subtropical jet will remain
south of the Tennessee Valley. Winter storms that far south often
overperform on their northern fringe with models likely overdoing
QPF on the northern periphery of the system where central Indiana
lies. The strong Arctic high to our north will maintain a steady
northeasterly wind through the course of the event advecting cool
and dry air into the area with dew points in the single digits to
low teens further complicates the QPF forecast. Latest guidance
trending further north and stronger warm air advection aloft
promoting greater moisture leads to lower confidence in this
scenario, but will continue to monitor closely.

Monday and Wednesday.

The pattern looks to remain active but cold heading through the
middle of next week, as a trough persists over the Eastern US
following the departure of the weekend system. This setup will
maintain northwest flow across central Indiana, keeping highs in the
20s and lows in the single digits or teens through Tuesday with
lower chances for sub-zero temperatures. A slight warm up is
possible Wednesday, but very cold temperatures are likely through
late next thanks to reinforcing shots of cold air. Even colder
temperatures are possible if there is a deep snowpack in place from
the weekend winter storm.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 559 PM EST Thu Jan 22 2026

Impacts:

- Gusty winds may linger this evening at KLAF

- Wind shift to northwest by 06Z with some gusts developing
  overnight

Discussion:

VFR conditions are expected through the period, with some mid cloud
a times.

A cold front will move through the sites in the first quarter of the
TAF period, switching winds to the northwest. Some gusts near 20kt
are possible with the frontal passage. However, gusts are more
likely later tonight and continuing at times Friday.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Cold Weather Advisory from 1 AM Friday to 10 AM EST Saturday for
INZ021-028>031-035>049-051-052.

Winter Storm Watch from Saturday evening through Sunday evening
for INZ021-028>031-035>041-043-044.

Winter Storm Watch from Saturday morning through Sunday evening
for INZ042-045>049-051>057-060>065-067>072.

&&

$$

SHORT TERM...Eckhoff
LONG TERM...White/Melo
AVIATION...50