Marion, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

436
FXUS63 KIWX 290500
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
100 AM EDT Mon Jun 29 2026

.KEY MESSAGES...

- Extreme Heat Warning in effect Monday afternoon into Thursday
  evening for an extended period of high heat indices and
  limited nighttime cooling.

- Heat may remain a concern Friday, but chances for showers and
  thunderstorms begin to increase resulting in lower confidence
  on the amount of impacts.

&&

.DISCUSSION...
Issued at 238 PM EDT Sun Jun 28 2026

BLUF...after extensive collaboration with surrounding offices, we
have decided to upgrade to an Extreme Heat Warning for the same
valid period as the watch. Will break down the pros and cons
shortly. We want to reiterate that regardless of the type of heat
related headline, they all convey the same thing...a focus on the
impacts of the heat to everyone. In addition to sensitive
populations, even those that routinely work outside or have A/C will
be impacted

Warming today has been somewhat limited by high clouds blowoff from
a persistent MCS to our west as well as some cu popping here and
there across the area. Radar and satellite data showing the complex
finally beginning to weaken. While the remnants could bring a quick
shower to northern portions of the area later this afternoon or
early evening models generally lean toward no impacts so pops will
be left below 15%. Additional upstream complex are expected over the
next day or 2, but should remain well north of the forecast area.

We then turn our attention to the bigger story of the dramatic
arrival of summer and extended period of increased heat and
humidity. A mixture of headlines surround us which may pose
challenges to our media partners in messaging. Monday will be the
"coolest" of the next several days with many offices leaning toward
handling this with a Heat Advisory and then look at a Watch or
eventual Warning in the later periods. For our area, even though the
same concerns exist, it was decided to keep messaging simple and
just upgrade to a warning for the extended period of impacts with
heat indicies AOA 100 degrees. There are factors that could cause
true criteria from being met at times both Monday and Thursday, but
it is the cumulative effects of heat and humidity, combined with
limited overnight cooling, that pose the greatest danger. Some model
trends are indicating the upper ridge may not fully settle over the
area and could shift east a bit faster to allow at least the chance
for a bit of convection. Friday may need headlines as well, but
concerns for either convective development across the area or
upstream complexes propagating into the region lead to greater
uncertainty. With the focus on the heat, little will be addressed
for now on the holiday weekend other than it will remain on the
warmer side with additional potential for showers and storms at
times.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 100 AM EDT Mon Jun 29 2026

Upper-level low is drifting ESE this morning and along with it,
a narrow area of showers and thunderstorms. This will avoid the
terminals and generally, VFR BKN ceilings will persits most of
the day before becoming SCT/FEW. Increasing pressure gradient
after sunrise with a modest area of low pressure noted over the
Central US, at odds with 1017mb high pressure over the eastern
Great Lakes.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Extreme Heat Warning from 2 PM EDT /1 PM CDT/ this afternoon
     to 8 PM EDT /7 PM CDT/ Thursday for INZ005>009-012>015-
     017-018-020-022>027-032>034-103-104-116-203-204-216.
OH...Extreme Heat Warning from 2 PM this afternoon to 8 PM EDT
     Thursday for OHZ001-002-004-005-015-016-024-025.
MI...Extreme Heat Warning from 2 PM this afternoon to 8 PM EDT
     Thursday for MIZ078>081-177-277.
MARINE...None.

&&

$$

DISCUSSION...Fisher
AVIATION...Brown