Lafayette, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

334
FXUS63 KIND 150719
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
319 AM EDT Wed Apr 15 2026

.KEY MESSAGES...

- Active pattern this week with near daily chances for showers and
  storms. Friday likely to be the driest day of the week.

- A few rounds of storms expected this afternoon into tonight across
Central and North Central Indiana. A few storms may be severe with
damaging winds as the main threat.

- Near record warm temperatures expected through Saturday with
multiple days in the 80s and lows in the 60s.

- Much cooler Sunday into early next week with the potential for
frost.

&&

.DISCUSSION (Today through Tuesday)...
Issued at 319 AM EDT Wed Apr 15 2026

An active weather pattern continues for the region this week with
multiple rounds of showers and thunderstorms forecast to move
through Central Indiana. Nearly the same synoptic set up is over
the Great Lakes and Midwest as the past several days as a strong
southwesterly baroclinc zone has set up from the Plains into the
Great Lakes. This semi-blocking pattern will remain in place through
the week with the most active period for Central Indiana tomorrow
afternoon through early Thursday then again on Saturday.

The pattern features a modest 80-90 kt southwesterly upper jet
extending from West Texas to the Great Lakes with several embedded
shortwaves. Underneath the baroclinic zone, these embedded
shortwaves have kept an elongated surface low/boundary from the
Texas Panhandle through Wisconsin, placing Central Indiana well
within the overall warm sector. A strong nocturnal low level jet
(LLJ) redevelops each night over Indiana, feeding the multiple
complexes of storms riding around the periphery of the overall
system. Based on where Indiana is located within the warm sector,
the best forcing for ascent and storm complexes remains closer to
the synoptic features to the north and west. However as these
overnight MCSs die, their leftover outflow boundaries sag southward
into Central Indiana. This exact scenario occurred yesterday with
afternoon storms developing along these remnant boundaries. CAMs
guidance does not do well in these weakly forced set ups with
remnant outflow boundaries; therefore, much of the short term
forecast will be based off persistence, observations, and how
everything evolves upstream. The short term forecast will be lower
confidence than usual regarding exact placement and timing of waves
of convective development this afternoon into Thursday. But high
confidence remains in the overall pattern and associated
thunderstorm threats.

Today and tonight...

Latest satellite imagery shows a large MCS over Michigan and far
Northern Indiana currently, progressing east along the warm front,
while an additional complex of storms develops over Iowa and
Northern Illinois closer to the elongated surface low and cold
front. An upper wave along the front range of the Rockies will work
to shift this entire system and baroclinic zone eastward over the
next 24 hours, placing the area of best forcing for ascent and the
storm track closer to Indiana with several rounds of storms expected
to impact the region.

Mainly dry conditions should persist for Central Indiana for the
rest of the morning and early afternoon hours as dry air and
subsidence on the south side of these MCSs keep convection out of
the area. However for later this afternoon and evening, keeping an
eye on what happens with the remnant outflow boundary from the
current MCS in Northern Indiana and how it interacts with a mid
level shortwave in the Arklatex region moving northeast toward the
Ohio Valley. This wave should provide the necessary forcing for
convection development this afternoon in Illinois and Indiana along
remnant boundaries in the warm sector. Unfortunately, it is difficult
to determine where exactly these boundaries will set up at the
moment. Current thinking is that areas along and north of I-70 have
the best storm threat after 17z this afternoon. The environment will
be more than conducive for severe weather as elongated hodographs
within an unstable airmass suggest. Weak mid and upper lapse rates
may limit the overall hail threat today, but high DCAPE values, and
steep low level lapse rates with 30-40 kts of effective shear should
be enough to support organized severe storms with a damaging wind
threat with isolated tornadoes.

Expect multiple rounds of convection going into tonight as the
overall storm system begins to shift east. The threat for severe
weather during the overnight hours should be more synoptically
driven as surface wave moves northeast into the Great Lakes with a
trailing front in Indiana. The increasing low level jet overhead
ahead of the approaching system will work to increase overnight
rounds of storms to the west/southwest which move into Central
Indiana. The environment overnight will also be conducive for
surface based severe weather within such a moist and unstable
environment with increasing wind shear. The main threat going into
tonight should still be damaging winds as largely unidirectional
flow and speed shear support upscale growth of complexes into lines
and bowing segments.

Thursday through This Weekend...

Ridging briefly builds in on Thursday as the overall system shifts
eastward...however another broad southwesterly baroclinic zone
quickly sets up over the Plains again with surface cyclogenesis
occurring over the upper Midwest. This will place Indiana and much of
the region back into a hot and  humid pattern within the warm sector
of the developing low. Expect a drying trend Thursday as ridging
builds in. Little to no cold air on the backside of the front means
another above average day with highs well into the 70s, but with
slightly lower humidity values due to subsidence under the ridge and
dry air mixing down.

As a strong warm sector becomes established on Friday over the
Plains and Midwest, Indiana will have one full day of dry and very
warm weather before the next threat for storms arrives on Saturday.
Models show that the surface low with this system will be unphased
and tracking ahead of its upper component. This will potentially
make Saturday`s system more diurnally driven rather than
synoptically forced. At this time, strong deep layer flow will be
parallel to the cold front which could be enough to form a line of
storms with damaging winds being the main concern. Outside of
storms, stronger gusts are likely Saturday and into Sunday since the
elevated portion of the system will be lagging behind. General gusts
Saturday could reach as high as 35-40 mph and around 25 mph on
Sunday.

There are still some differences on when the associated cold
front would exit, but likely sometime late Saturday into the
overnight hours, behind which cooler and below normal temperatures
will return at least for the first couple of days of the new week.
Lows Monday morning could be approaching near freezing to mid-30s.
Surface high pressure behind the front looks to track over the Ohio
Valley, allowing for dry weather for the start of the new week as
well.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 150 AM EDT Wed Apr 15 2026

Impacts:

- Mainly SSW winds through the TAF period, gusting to 17-25KT
- Non-zero chances of additional convection this evening
- Multiple rounds of convection 17z Wed - 12z Thu

Discussion:

Mainly VFR conditions will prevail across central Indiana this
evening as satellite imagery shows most of the convective activity
in the region well to the west or north. The region remains well
within the warm sector of an area of low pressure to the northwest.
Waves of energy within the SW flow aloft interacting with leftover
boundaries will likely be the focus for thunderstorm development
this afternoon into tonight. Mainly VFR cigs and vis outside of
storms for the majority of the period. After 17z, widely scatter
storms should begin forming along leftover boundaries. Low
confidence in exactly where these boundaries set up, however
thinking the set up and evolution will be very similar to Tuesday
where the greatest threat is along and north of I-70. Kept Prob30
groups for TSRA after 17z at KLAF, KIND, and KHUF where the greatest
threat is. Will be able to fine tune exact timing in later forecast
issuances once boundaries set up. Brief periods of MVFR or worse
conditions with erratic wind speeds and directions under any storm.
With numerous waves of showers and storms expected to move through
the area, keeping the threat for storms through the end of the TAF
period.

Outside of storms, breezy, south-southwest flow to prevail through
the period, with slight changes in direction possible, especially
near any showers. Took out any mention of LLWS overnight through the
early morning hours as the boundary layer is remaining well mixed
according to obs and local ACARS soundings. Wind gusts of 15-25 kts
should prevail through the period.


&&

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

$$

AVIATION...CM
DISCUSSION...CM