Lafayette, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

521
FXUS63 KIND 201730
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
130 PM EDT Sat Jun 20 2026

.KEY MESSAGES...

- A few showers are possible today, mainly this morning north of
  I-70

- Heavy rain and isolated severe storms are possible Sunday
  afternoon into early Monday as widespread rain moves in

- Below normal temperatures will continue for much of the period.

&&

.FORECAST UPDATE...
Issued at 1001 AM EDT Sat Jun 20 2026

Minor tweaks to the forecast to extend sprinkles for a few more
hours in the N-NE. Also nudged highs up a bit in the north with sun
expected most of the afternoon.

Concerns for tomorrows weather setup continues with expectation for
multiple rounds of potential severe weather starting mid-late
afternoon in the SW portions of the forecast area. Followed
by flooding threat increasing overnight.

&&

.DISCUSSION (Today through Friday)...
Issued at 259 AM EDT Sat Jun 20 2026

...HEAVY RAIN AND STRONG STORMS POSSIBLE SUNDAY AND SUNDAY NIGHT...

Today and Tonight...

A weak cold front will move into central Indiana today. The front
will have little upper support, and overall moisture is lacking.
However, the front may squeeze out some isolated showers/scattered
sprinkles across mainly the northern half of the area this morning.
Will have some low PoPs for these.

By this afternoon, forcing will be weak enough that PoPs will drop
below mentionable thresholds. However, some CAMs show that just
enough moisture/instability will be around for a shower or two to
pop up across the southern half of the area. Will have to keep an
eye on it, but for now will go dry.

Tonight will be quiet with the area in between systems.

Highs today will be in the upper 70s to lower 80s, with lows tonight
around 60 for much of the area.

Sunday into Monday...

An upper trough, surface low pressure, and a low level jet will
create a Mesoscale Convective System (MCS) to the west which will
move into central Indiana Sunday afternoon into the evening. A warm
front will move into the area as the surface low moves closer during
the day. The low level jet will bring in plentiful moisture to the
area, with anomalously high moisture transport and precipitable
water values expected.

Showers and storms will continue Sunday night as the low pressure
system moves through, then rain chances diminish Monday as the
system exits. Will go high PoPs all areas by early Sunday evening
and will continue them Sunday night.

Shear and instability will be enough that isolated severe storms are
possible with the initial MCS, especially near and south of where
the warm front sets up. The severe threat may increase across the
far southwest Sunday evening as thunderstorms developing along an
outflow boundary from the initial storms across southern Illinois
move into the area. These will have more shear to work with and
could produce isolated tornadoes, mainly across the far southwestern
forecast area.

With recent heavy rains, the expected high moisture content of the
atmosphere, and the potential of training storms along the system`s
warm front, the threat for heavy rain will be high. Some guidance is
showing convection exceeding 3 hour flash flood guidance, especially
south. Will issue a Flood Watch for this threat. With some
uncertainty in where the heaviest rain will fall, will go for all
but the northeast forecast area for now, from Sunday afternoon to
Monday morning.

There remains some questions with this system. There is the
potential for multiple convectively induced waves of low pressure
that may enhance storms/rainfall and change the location of the warm
front. Even without this, there is some uncertainty on where the
warm front will set up. Some guidance is also showing a split in
heavier QPF, with some of it moved farther south and some going
farther north than currently expected.

Depending on the timing of the MCS, highs on Sunday could reach the
lower and middle 80s south and the upper 70s north. Temperatures
will be cooler and in the 70s for highs Monday as the system exits.

Tuesday and beyond...

Some upper waves and surface fronts could bring rain chances at
times Wednesday into Friday, but confidence isn`t high enough to go
more than some low PoPs. The GFS is hinting at another stronger
system next weekend, but the ECMWF isn`t as bullish. Northwest flow
aloft will keep temperatures below normal.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 130 PM EDT Sat Jun 20 2026

Impacts:

- Gusty winds this afternoon around 20 kts

- Showers developing midday.

- Scattered thunderstorms expected late Sunday afternoon near IND.

Discussion:

Isolated showers are still possible this afternoon, but should
remain well south-southeast of KIND/KBMG. Otherwise, the only
sensible weather concern this afternoon is some wind gusts up around
20 kts from the West to WNW as a weak boundary moves south through
the terminals. Scattered to BKN VFR ceilings will gradually diminish
with loss of heating as will the wind gusts around 23Z.

Overnight, mid level clouds will begin to increase ahead of a storm
system over the plains. Weak surface high pressure will lead to
light and variable winds and VFR conditions.

On Sunday, expecting winds to become SE with some gust possible as
high as 15 kts by midday ahead of a developing low pressure area
over MO. Associated with this low pressure area, expecting a complex
of thunderstorms, gradually weakening to move into central Indiana
towards midday. VCSH will be carried at most TAF sites by midday.
Renewed convective development is expected to develop over IL during
the afternoon with the potential for some of that to move into KIND
towards late afternoon so have PROB30 in the forecast to account
for this potential.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Flood Watch from Sunday afternoon through Monday morning for
INZ028>030-035>037-039-043>048-051>057-060>065-067>072.

&&

$$

UPDATE...Crosbie
AVIATION...Crosbie
DISCUSSION...50