541
FXUS63 KIND 170045
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
845 PM EDT Mon Mar 16 2026

.KEY MESSAGES...

- Snow showers overnight with a dusting to under one inch
  possible most areas.

- Potential for slick spots/flash freeze overnight.

- Wind chills near zero Tuesday morning.

- Light snow likely late Tuesday night into early Wednesday with
  up to one inch possible.

- Above normal temperatures return late week with highs in the 70s
  possible Friday and Saturday.

&&

.FORECAST UPDATE...
Issued at 845 PM EDT Mon Mar 16 2026

Central Indiana will continue to see snow showers through the
overnight period as strong CAA in the low levels maintains steep low
level lapse rates and instability. The main difference between
tonight`s snow showers and the snow we had earlier today will be the
location of lift and saturation in the lowest 3km. Early today, the
lowers 3 km remained mostly saturated leading to more cellular like
snow bursts. Tonight, the expectation is for a more stratified look
with potentially narrow corridors of light accumulation due to
greater longevity of strongest bands over specific areas. That said,
snow rates within the bands should be weaker than earlier this
afternoon, and thus even within one of the narrow bands accumulation
on grassy surfaces should remain less than 0.5".

&&

.SHORT TERM (This evening through Tuesday)...
Issued at 309 PM EDT Mon Mar 16 2026

Strong low pressure to our north has promoted cold air
advection through the day today. Temperatures have been gradually
falling despite filtered daylight. Model soundings indicate
steepening lapse rates this afternoon within a PBL as deep as 700mb
(10,000 feet), leading to near-surface instability between 25-75
J/KG 3CAPE. Combined with rich low-level moisture, Snow Squall
parameter is between 3-5 currently and is expected to remain there
through the afternoon. As such, locally heavy snow showers are
likely today. Given the lack of strong forcing, these should be
fairly cellular in nature. Furthermore, there is not Arctic air
advection thus mitigating the flash-freeze potential. Still, the
heaviest of these snow showers may lead to reduced visibility as low
as 1/4 mile and briefly snow-covered roadways.

By tonight, conditions change slightly as ground temperatures
continue to cool during the day. By sunset, the impact of diluted
sunlight will be over and flash-freeze potential begins increasing.
Snow showers are expected to continue into the night with steep PBL
lapse rates and broad cyclonic flow. Some of these snow showers may
be heavy at times. Snowfall has greater chances of accumulating
this evening and into tonight. Most locations should see between a
dusting to an inch, with a few pockets of 1-3 inches, primarily
where multiple heavy snow showers occur. Driving conditions may be
locally hazardous throughout the night.

Temperatures continue falling through the night despite cloud cover,
breezy conditions, and snow. Lows in the teens are anticipated with
wind chills in the single digits.

Snow showers likely continue into the early morning hours on Tuesday
before tapering off. Continued cyclonic flow and rich boundary layer
moisture will allow low stratus to continue. Tuesday is expected to
be mostly cloudy, and this will keep high temperatures suppressed.
Highs near 30 are expected across the area with colder readings to
the NE and warmer to the SW.

&&

.LONG TERM (Tuesday night through Monday)...
Issued at 309 PM EDT Mon Mar 16 2026

Tuesday night and Wednesday...

A weak clipper system will effect the area through Wednesday
morning. The system will have decent mid level WAA/isentropic lift
and some assistance from an upper jet. This will likely bring some
light snow to the area, with accumulations up to around an inch
possible.

Temperatures will warm quickly Wednesday, melting any snow. Highs
will top out in the mid 40s to mid 50s, just below seasonal norms
for mid-March.

Thursday through Saturday...

A large upper ridge across the western CONUS will gradually shift
eastward into the plains during the period, while becoming flattened
on the northern periphery owing to shortwave energy moving along the
CONUS/Canadian border. Ahead of the building ridge, a weak shortwave
will move SE across the Great Lakes into the Ohio Valley which
main bring some light rain on Thursday. Therefore have kept low PoPs
in the forecast. Breakdown of the ridge will support increasing SW
winds, advecting higher moisture/PWAT values 50% above normal and
much warmer than normal temperatures going into the weekend.
GEFS/EPS have 8-10 C 850 temperature anomalies peaking on Saturday.
As a result, NBM temps appear too cool Friday and Saturday. Highs in
the mid-upper 70s are more likely by Saturday per the operational
Euro.

Sunday and Monday...

A strong cold front is well handled by the models by Sunday-Monday
time period bringing with it chances of rain and temperatures
cooling to near or just below normal by Monday

&&

.AVIATION (00Z TAF Issuance)...
Issued at 729 PM EDT Mon Mar 16 2026

Impacts:

- Scattered to numerous snow showers, IFR or even LIFR possible in
  heaviest snow showers.
- WNW wind gusts near 30kt continue through the evening, 25kt
  overnight

Discussion:

Strong cold air advection is in place with an unstable air mass
overhead. This has resulted in widespread snow showers across
central Indiana. Conditions favorable for snow shower formation will
persist through tonight. Since snow showers are scattered in nature,
a tempo group was included for brief visibility reductions to IFR/
LIFR.

Otherwise, MVFR ceilings are expected to persist through at least
12Z, potentially raising just into VFR tomorrow morning. West-
northwesterly winds have been steady in the 20-25kt range with gusts
between 30-35kt. That should continue tonight before a gradual
diminishing trend begins. Gusts should start to subside tomorrow as
the trough pushes well off to the east.


&&

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

$$

UPDATE...Updike
SHORT TERM...Eckhoff
LONG TERM...Crosbie
AVIATION...Updike