Lafayette, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

186
FXUS63 KIND 260427
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1227 AM EDT Fri Jun 26 2026

.KEY MESSAGES...

- Flood Watch from late this afternoon through Saturday morning for
  southwest portions of central Indiana with 1 to 3 inches of rain
  possible

- Multiple rounds of showers and storms producing torrential
  rainfall and localized flooding later today into the weekend

- Isolated severe storms possible this afternoon and evening and
  again on Friday

- Hot and humid conditions expected for much of next week with
  multiple days in the 90s

&&

.FORECAST UPDATE...
Issued at 956 PM EDT Thu Jun 25 2026

Stubbornly persistent very isolated convective cells continue to wax
and wane across portions of central Indiana this evening, despite
the expected general downward diurnal trend in both coverage and
intensity.

The going forecast is in very good shape, with no significant
changes necessary. Expect mostly quiet weather through the remainder
of the evening into the early overnight, before chances begin to
ramp back up again late tonight as weak upstream convection moves
into the area associated with a subtle upper level wave moving along
the boundary in the region. A few rumbles of thunder will be
possible with this and perhaps a brief heavy downpour or two, but
the more significant convective concerns should hold off until the
later daytime into evening hours tomorrow.

Some patchy fog will be possible overnight due to light winds and
ample low level moisture, though cloud cover will limit radiational
cooling and should equally limit fog coverage, though will have to
keep an eye on it with the aforementioned boundary remaining in the
area.

&&

.DISCUSSION (This evening through Thursday)...
Issued at 134 PM EDT Thu Jun 25 2026

A ridge over the Intermountain-West along with weak troughing over
Eastern Canada is creating a strong jet streak over the Upper
Midwest today leading to a corridor of broad synoptic lift. This in
combination with a mostly saturated 925-700mb layer and weak mid-
level instability will likely lead to pockets of showers and
thunderstorms throughout the afternoon and into the evening. These
showers should mainly be diurnal, as cooling post dusk should cap
the environment and prevent initiation with forcing primarily
attached to synoptic scale jet dynamics.

Most of these showers and storms should remain mundane, but there is
enough upper to mid level shear for a few pockets of organized
clusters to form this afternoon once updrafts are able to reach 18-
20kft. For this reason a few isolated damaging wind gusts cannot be
ruled out, primarily south of the I-70 corridor. The other potential
concern this afternoon and evening will be localized flooding. The
primary area to watch will be along and south of a line from Sullivan
to Bedford, as over this area are a few lingering, old outflow
boundaries and slightly lower flash flood thresholds due to prior
rainfall. Rain rates will be fairly efficient with this storm
clusters and anywhere in this area that receives 2-3" in a 3 hour
period will be susceptible to flooding.

For tomorrow, the primary forcing will switch to a more organized
mid-level shortwave of which will likely produce numerous to
widespread showers and thunderstorms throughout the day. Initially,
modest isentropic lift ahead of the wave will likely push
thunderstorms into Indiana between 6-9AM. Although severe weather is
unlikely with this first round, a narrow corridor of 750-1500 MUCAPE
south of I-70 could lead to a few strong updrafts with small hail
and gusty winds.

The primary severe threat will be later in the day as
destabilization occurs in a quasi-warm sector. Low level
cyclogenesis is expected across IL throughout Friday, but the
magnitude of pressure depletion is still widely varied amongst
ensemble members. The current most likely scenario is for weak
pressure depletion and the greatest zone of 30kt+ shear and
1500m2/s2 of instability to remain over far SW and S central
Indiana. However, there are a few members hinting at deeper
cyclogenesis and therefor a greater push northward in favorable
parameter spacing. Within this zone, all severe hazards will be
possible, but the primary threat will be isolated tornadoes and
damaging wind gusts.

Flooding will also be a potential hazard tomorrow as generally these
showers and storms will remain over the same areas throughout the
day. Each individual storm will likely progress quick enough to
avoid issues, but the consistency of initiation could lead to narrow
swaths of training storms and 2-4 inches of rainfall.

After the passage of the wave, weak CAA will attempt to push a
boundary through central Indiana Friday night, but the forcing will
quickly push eastward, likely stalling the boundary over the Ohio
Valley on Saturday. This will likely lead to additional showers and
storms, with a low threat for isolated damaging wind gusts within
microbursts. These storms are likely to move slower due to lack of
steering flow, creating an additional flood threat Saturday
afternoon and evening.

In the wake of convection late on Saturday, the upper ridge will
expand into the area with the front lifting away to our north. This
will serve as the transition point towards progressively hotter and
more humid conditions that are likely to last well into next week.
Multiple days with highs in the 90s are anticipated through much of
next week with the highest heat indices of the summer so far rising
into the low 100s during the afternoons. Isolated late afternoon and
evening convection may develop by the second half of next week as
the mid level heights begin to fall back. As the upper ridge will
retrograde back to the southwest by next weekend, will need to
monitor for an increased risk for convective clusters riding along
the periphery of the ridge impacting parts of the region.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1227 AM EDT Fri Jun 26 2026

Impacts:

- Rain spreading across the area towards daybreak

- Numerous showers throughout the day with thunder possible as well
  during the afternoon and early evening

- Poor flying conditions developing shortly after daybreak and
  persisting through tonight

Discussion:

Most of the convection has diminished across central Indiana early
this morning with rain and storms confined to the lower Wabash
valley and points to the south and west in the vicinity of a
stagnant frontal boundary. Convection over the mid Mississippi
Valley will lift northeast towards the region during the predawn
hours and overspread the terminals after 09Z through mid morning.
MVFR stratus will accompany the showers with ceilings steadily
dropping throughout the morning.

The approach of a surface wave as the boundary oscillates back into
area will bring numerous showers and scattered thunderstorms for the
afternoon with the potential for IFR and lower visibilities briefly
within any convection that impacts the terminals. Showers should
become more scattered in coverage tonight as the front lingers over
central Indiana in the wake of the surface low moving away to the
east. IFR ceilings will persist through the afternoon and likely
through tonight as well.

Light and variable winds early this morning will largely transition
to E/SE for much of the day with the possibility of more chaotic
wind directions this evening as the low passes through the area.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Saturday morning for INZ051>053-060>065-
067>072.

&&

$$

UPDATE...Nield
AVIATION...Ryan
DISCUSSION...Ryan/Updike