Lafayette, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

223
FXUS63 KIND 140714
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
314 AM EDT Sun Jun 14 2026

.KEY MESSAGES...

- Showers and thunderstorms likely today.

- Much cooler temperatures through Tuesday night with highs in the
  low-mid 70s and lows in the 50s

- Wednesday-Thursday: overall seasonable warmth/humidity...with
  potential for multiple rounds of unsettled weather

- Severe weather possible on Wednesday

&&

.DISCUSSION (Today through Saturday)...
Issued at 314 AM EDT Sun Jun 14 2026

Widely scattered showers and a few thunderstorms have been observed
across central Indiana since Midnight but coverage is very low. Will
maintain slight chance PoPs in areas that showers are occurring,
trimming PoPs elsewhere, before allowing precip chances to increase
towards dawn.

A potent short wave trough embedded in a larger long wave trough
will swing through this afternoon. At the surface, a cold front is
advancing from the northwest. Though low-level flow is weak,
moisture advection continues ahead of the approaching boundary.
Filtered sunshine this afternoon should lead to modest boundary
layer destabilization, resulting in between 500 to 1500 J/Kg MLCAPE.

Showers and thunderstorms are likely this afternoon, initiated by
the front and aided by synoptic forcing. Thunderstorm intensity may
be mitigated by poor mid to upper-level lapse rates. Though storms
may be scattered to numerous, the relatively weak updrafts will
limit severe weather potential. A few severe storms cannot be ruled
out, however, since around 40kt of bulk shear may allow for some
storm-scale organization. Damaging winds would be the primary
hazard, given a quasilinear storm mode forced by the front.

Northwesterly flow intensifies later this afternoon after the front
sweeps through. Winds may gust to 20-25kt at times before surface
high pressure arrives overnight. Wind speeds decrease quickly,
becoming calm to light and variable. Patchy fog may be possible at
times across the region tonight, especially in rural areas.

Broad troughing remains over the northern CONUS this week with
multiple waves embedded within the quasi-zonal jet stream that
rounds its base. These waves may bring periodic cloudiness and even
rain chances at times Monday and Tuesday. By Wednesday, a more
potent wave arrives with the potential for thunderstorms and severe
weather. Broad troughing persists through the week and into the
weekend. Temperatures this week are expected to remain near to below
normal due to the persistent troughing.

WEDNESDAY SEVERE POTENTIAL

Digging a bit deeper into the system poised to bring active weather
back to the region, we see fairly good agreement within
deterministic guidance. Global models show a very low amplitude
shortwave rounding the base of the broader trough on Wednesday. This
enables cyclogenesis over the upper Midwest, with the resulting
surface low tracking east into the Great Lakes. A potent low-level
jet then develops in response to the deepening low, allowing for
strong warm air and moisture advection northward. Additionally, the
upper-level jet stream remains overhead. Model hodographs are long
and curved, with a southeasterly mean shear vector.

A few scenarios exist regarding convective evolution. First, the
strong warm moist advection may be sufficient to initiate convection
Tuesday night far upstream over Iowa. This could consolidate into an
MCS and propagate southeastward into the strong low-level jet and
warm moist advection, aided by southeasterly shear. Damaging winds
and localized flooding would be the primary hazards in such a
scenario.

Second, there is no early convection and or the atmosphere recovers
from earlier storms (strong low-level jet may easily allow this to
happen even if there is morning convection, simply by advecting the
rain cooled air mass northward). Atmospheric instability is
maximized by continued strong warm moist advection and solar
insolation. Thunderstorms initiate along the surface cold front over
Illinois and propagate southeastward. Shear vectors perpendicular to
the advancing front may allow for discrete mode initially, with
potential for supercells. All hazards are possible in this
circumstance. Eventually, convection would grow upscale becoming
primarily a wind threat.

There are a lot of moving parts with this, and predictability is
currently low to medium. Guidance still needs to properly resolve
the initiating wave and surface low. Additionally, the potential for
early convection is always a wild card and can substantially alter
the pre-storm environment. Given the potential for a strong low,
potent low-level jet and shear, it is certainly worth watching over
the coming days.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 314 AM EDT Sun Jun 14 2026

Impacts:

- Chance for -SHRA between 14-19Z today, thunderstorms possible
- MVFR ceilings likely after 08-11Z today
- Wind shift to northwesterly within 14Z-18Z

Discussion:

A cold front is approaching from the northwest and will bring
showers at times and possibly a thunderstorm. Showers/storms will be
scattered so VCSH will be carried as a prevailing and a Prob30 is
added for potential impacts.

MVFR ceilings are expected to develop this morning as boundary layer
moisture increases. MVFR conditions could persist through the
morning hours.

The cold front itself passes through during the course of the
afternoon, causing winds to become northwesterly. Gust to between 20-
25 knots are possible at times.

Winds diminish quickly tonight as surface high pressure builds in.
Patchy fog is possible, especially if winds become calm or light and
variable.

&&

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

$$

AVIATION...Eckhoff
DISCUSSION...Eckhoff