Lafayette, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

762
FXUS63 KIND 170541
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1241 AM EST Wed Dec 17 2025

.KEY MESSAGES...

- Temperatures warming through Thursday

- Widespread rain likely Thursday with QPF amounts generally ranging
  from 0.5 to 1.25 inches, minor flooding possible

- Wind gusts between 25-35 mph possible Thursday and Thursday night,
  slightly higher gusts cannot be ruled out during the day

- Flash Freeze possible Thursday night/early Friday as temperatures
  could fall 20-30 degrees in 12 hrs

- Above normal temperatures expected next weekend into Christmas
  week

&&

.FORECAST UPDATE...
Issued at 953 PM EST Tue Dec 16 2025

An area of lower clouds has moved into the southeast two-thirds of
the area, but radar and surface observations aren`t showing any
sprinkles with it. Have thus removed these from the forecast.

These clouds along with southwest winds are also keeping
temperatures warmer, so raised hourly temperatures where needed.
This lower cloud deck will exit overnight.

High clouds will continue, with perhaps more lower clouds arriving
late tonight from the northwest with a surface trough. At the
moment, moisture and forcing aren`t great, so confidence is low in
drizzle occurrence.

Low temperatures look reasonable given lower clouds exiting for a
period overnight. Will continue to monitor.

&&

.SHORT TERM (This evening through Wednesday)...
Issued at 331 PM EST Tue Dec 16 2025

Central Indiana will see warming throughout the short term
as southerly flow dominates. Warm air advection will allow lows near
freezing tonight and highs near to slightly above normal tomorrow.

Tight pressure gradients aloft, associated with a surface low
tracking eastward and north of the Great Lakes, will bring breezy
conditions this evening into the morning hours. Gusts could be as
high as 25-30 mph.

Additional low level clouds will be likely across the south tonight.
Currently the stratus deck is moving ENE across the Ohio Valley,
extended back into Missouri. Can`t rule out a few sprinkles out of
these clouds but it is not looking likely as model soundings look
too dry through the column.

Confidence is lacking on exactly how warm temperatures will get
tomorrow as it will depend on how far north the warm front off of an
approaching low pressure will reach within the area. For now have
highs in the upper 30s across the north and almost 50 in the far SW
but temps may be slightly higher or lower than forecasted based on
where the warm front ends up prior to sunset.

Given the warmth expect snow to melt through the period and beyond.
But this does bring a concern to keep an eye on this week, which is
the potential for ice jams forming along rivers and creeks. Should
these form, quick changes in river levels may be possible and if bad
enough, could produce minor flooding.

&&

.LONG TERM (Wednesday night through Tuesday)...
Issued at 331 PM EST Tue Dec 16 2025

Wednesday night through Friday...

A quick moving wave aloft and strong low pressure system will push a
cold front through the region early in the extended. Initially,
expect an associated warm front to advance northward overnight
Wednesday leading to increasing warm air advection. This may support
light rain or drizzle late in the night before deeper moisture and
stronger forcing overspreads central Indiana after daybreak. Look
for widespread rain through much of the day Thursday with QPF
amounts generally ranging from 0.5 to 1.25 inches. Far northwest
parts of the forecast area could see less than half of an inch due
to less available moisture.

Strong southerly flow favors temperatures warming into the
upper 40s to low 50s despite rain through the day. Sustained winds
around 15-20 mph are anticipated as the MSLP gradient tightens.
Marginal daytime mixing may promote wind gusts between 25-35 mph. It
is not out of the question for any heavier showers to potentially
mix down even stronger gusts.

The cold front will likely sweep through during the evening hours
ushering in colder drier air. Some light snow may begin mixing in
once temperatures quickly start falling around the evening. Latest
guidance suggest a mid-upper level vort max will still be overhead
through Friday morning along with broad low-level cyclonic flow.
This supports the potential for isolated light snow showers and
flurries to persist overnight, possibly into Friday morning. Minor
snow accumulations cannot be ruled out since both road and air
temperatures will rapidly fall. Stay tuned as this may lead to slick
road conditions during the morning commute Friday.

Rapidly falling temperatures Thursday night also leads to some
concern for a flash freeze with any lingering moisture on roadways.
Air temperatures should fall from the mid 30s to low 40s in the
evening to near or below freezing by midnight for much of central
Indiana and then into the teens to low 20s late overnight. Some
uncertainty remains on the threat though as breezy conditions should
help to evaporate moisture on the roads and road temperatures will
lag behind air temperatures.

Expect increasing heights aloft and surface high pressure building
in Friday. This will provide quiet weather conditions much of the
day, outside of the potential for slick road conditions in the
morning and a low chance for flurries or light snow shower over the
far east. Highs in the upper 20s to low 30s combined with breezy
conditions early will lead to cold wind chills in the single digits
to teens in the morning.

Friday night through early next week...

Mostly quiet weather is expected during the latter half of the
extended. Another upper wave and low pressure system will move
through the Great Lakes region sweeping a cold front through central
Indiana. Precipitation is unlikely due to the strongest forcing
remaining north, but a stray rain or shower cannot be completely
ruled out. Another subtle feature may move through late Sunday into
early next week bringing a low chance for precipitation, but
confidence is very low due to diverging model solutions. Look for
temperatures to cool down briefly into Sunday before warming up
again next week heading into Christmas.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1241 AM EST Wed Dec 17 2025

Impacts:

- Low-level wind shear between 00z to 12z
- SW wind gusts to 20kt before 12z
- MVFR ceilings developing after 00z
- Low-level wind shear returns after 04z

Discussion:

A trough is passing to the north of Indiana and has allowed SW winds
to increase to around 10kt, gusting to 20kt. Additionally, a low-
level jet ahead of the system`s surface cold front is promoting low-
level wind shear around 40kt. Diminishing winds and wind shear,
along with cloud cover, is expected after the front passes around
12z. A low chance of drizzle/sprinkles exists with the front,
especially further northwest near LAF.

Brief surface high pressure should bring VFR conditions with light
and variable winds later this morning into the early afternoon.

However, a second system approaching from the NW will arrive
tonight. Like the previous trough, this one is expected to pass to
our north promoting strong southwesterly winds. Wind shear once
again develops and could exceed 50kt after 06z.

Additionally, strong moisture advection will bring MVFR ceilings
back to central Indiana overnight into Thursday. Rain is likely
after the end of the TAF period during the day on Thursday.

&&

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

$$

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