Lafayette, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

347
FXUS63 KIND 301441
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1041 AM EDT Tue Jun 30 2026

.KEY MESSAGES...

- Hot and humid conditions expected with highs in the 90s and heat
  indices peaking at 105 to 110 degrees in the afternoons through
  Thursday

- Extreme Heat Warning in effect through Thursday evening

- Thunderstorm chances will increase Friday through the holiday
  weekend

&&

.FORECAST UPDATE...
Issued at 1041 AM EDT Tue Jun 30 2026

No significant changes to the going forecast this evening.

High pressure with hot and humid conditions are solidly impacting
the region. Much of the forecast area has already reached 80
degrees with dew points in the upper 70s by mid morning. Skies
will be mostly sunny today with a Cu field likely at times and
some passing upper cirrus as well.

&&

.DISCUSSION (Today through Monday)...
Issued at 237 AM EDT Tue Jun 30 2026

Muggy early this morning as with the center of the upper ridge
across the Ohio Valley. 06Z temperatures remained between 75 and 80
degrees with dewpoints well into the 70s.

A dangerous heat wave will continue for much of the rest of the week
as deep ridging sets up over much of the eastern half of the
country. The ridge will flatten by late week as the jet stream
drifts back south into the area. Scattered convection largely
prevalent on any waves rippling through the flow will increase for
the holiday weekend as a result.

The primary focus will be on the heat and humidity with at least 4
or 5 consecutive days with highs in the 90s. Monday was day one with
highs in the lower 90s and heat indices that peaked over 100
degrees. Expect warmer air temperatures and higher heat indices
today through Thursday with the core of the ridge over the area as
mid level heights peak at 596-598dm. Increased subsidence over the
Ohio Valley will limit clouds and diurnal cu as well...especially
today and Wednesday. Likely to see a slight increase in cu
development Thursday as moisture pivots around the back side of the
ridge and into the area...but it is shallow and should not have much
impact on expected highs.

Low level thermals support low to mid 90s each of the next three
days with dewpoints remaining in the 70s. Max heat indices of 105 to
110 degrees are possible each afternoon. Considering the intensity
of the heat with the compounding nature of impacts over multiple
days from the oppressive airmass have elected to upgrade the Heat
Advisory to an Extreme Heat Warning through Thursday evening. An
increase in outdoor activities in advance of the Independence Day
weekend also factored into this decision to upgrade. An argument
could be made to extend the warning into Friday even as temps and
heat indices fall back slightly from levels expected through
Thursday...but increasing uncertainty on convective potential
beginning Friday precludes an expansion in time at this point.

The ridge will slowly flatten heading into the weekend as waves
aloft drift further south into the lower Great Lakes and Ohio
Valley. Convective coverage should steadily increase Friday into the
weekend as the mid level heights begin to fall back. Locally intense
slow moving storms producing damaging winds during the afternoon and
evening will be a possibility within the moist and highly unstable
airmass. There remains the possibility of one or more mesoscale
convective systems impacting parts of the region by the weekend as
well...and there is already CIPS analog support for this solution by
Saturday and Sunday. Very warm and humid conditions will linger into
early next week.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 532 AM EDT Tue Jun 30 2026

Impacts:

- Wind gusts may peak at 15-20kts at times this afternoon mainly at
  KLAF

 Discussion:

VFR conditions are likely to prevail throughout the period.

Mostly clear skies are expected through much of the period as the
region resides under ridging at the surface and aloft. Southerly
flow this morning will veer to southwest this afternoon and increase
to 10 to 15kts at times. A sporadic higher gust is possible this
afternoon as well...especially at KLAF. Winds will diminish near
sunset.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 8 PM EDT Thursday for INZ021-028>031-
035>049-051>057-060>065-067>072.

&&

$$

UPDATE...KF
AVIATION...Ryan
DISCUSSION...Ryan