Portage, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

363
FXUS63 KIWX 280740
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
340 AM EDT Sat Jun 28 2025

.KEY MESSAGES...

- Brief reprieve from the muggy conditions today before
  humidity levels increase somewhat for Sunday into Monday.
  Highest heat indicies Sunday in the mid to upper 90s.

- Cold front brings a chance for showers and storms Monday
  afternoon and evening. Locally heavy rain and gusty winds will
  be the main threats.

- Remainder of the period will be dominated my highs in the 80s
  and lows in the 60s with more typical humidity levels. Heat
  related impacts are not expected.

&&

.DISCUSSION...
Issued at 332 AM EDT Sat Jun 28 2025

A subtle boundary extended from central IN to our far SE CWA.
Some new convection has been developing moreso across central IN
and could possibly expand somewhat NE to clip the far SE areas,
so will maintain the slgt chc pops in that area prior to 12Z.
The main "cool front" was taking its sweet time working SE
across NW IN/SW Lower MI with mid 60 dewpoints behind it and
event lower values (mid to upper 50s) in portions of WI. The
"drier" air will slowly work through the forecast area today,
with dewpoints everywhere dropping into the 60s (lowest NW) by
afternoon which will feel much better after the extended
tropical type airmass. Some stratus was noted across WI but
models seem to either dissipate this or shift more eastward so
we should see a good deal of sunshine today. The front will
begin to return back north Sunday into early Monday, bringing
the higher dewpoints back for another, much briefer visit. Highs
Sunday will climb well into the 80s and can`t rule out a few
90s, but heat indicies should remain just below advisory levels
(in the 90s) so headlines don`t appear likely at this point.

A somewhat stronger trough will dive southeast and deepen somewhat
as it moves across the Great Lakes Monday into early Tuesday. The
overall atmosphere will have similar characteristics to what we have
dealt with the past several days with 1000 to 1500 J/KG of MLCAPE,
modest shear and minimal lapse rates resulting in more of a pulse
storm setup (maybe some loosely organized mulit-cell clusters) and
associated marginal wind threat and locally heavy rain. Some models
hint at more of a pre-frontal trough sparking scattered to numerous
showers and storms through the day Monday before the main cold front
arrives Monday night with somewhat better shear profiles. By this
time, the area could be worked over resulting in little additional
development. The new SPC DY3 has added a marginal risk to
essentially the entire CWA to account for these concerns. If
convection has less overall coverage ahead of the front, a somewhat
higher severe threat could materialize as the front sweeps through.

More appreciable lowering of dewpoints will occur late Monday and
persist through the remainder of the period (generally low to mid
60s) with more seasonable highs in the low to mid 80s. Some token
slight chc to chc pops remain in the later periods as a frontal
boundary may be draped somewhere in the area on the edge of the
somewhat increased ridging aloft.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 112 AM EDT Sat Jun 28 2025

A weak cold front has cleared KSBN (as noted by the dew points
in the 60s). This front will continue to seep east and south
eventually resulting in a veering wind at KFWA. High pressure
otherwise today will promote VFR conditions.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Fisher
AVIATION...Brown