568
FXUS63 KIWX 281840
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
240 PM EDT Sat Jun 28 2025

.KEY MESSAGES...

- Seasonable today with comfortable humidity!

- Slightly warmer and becoming increasingly humid on Sunday and
  Monday.

- Rain/storms are likely Monday afternoon and evening. A few storms
  could be strong to severe.

- Dry, warm, and less humid by midweek.

&&

.DISCUSSION...
Issued at 238 PM EDT Sat Jun 28 2025

We finally have some reprieve from the week-long heatwave! A `cool`
front has passed through the area and in its wake, northwest winds
are pushing in drier air and slightly cooler temperatures. Expect
highs to top out near seasonable levels the low to mid 80s. With the
drier air working its way in, expect clouds to decrease this evening
and lows to drop into the mid 60s. Overnight and into Sunday
morning, radiational cooling should allow for some patchy, shallow
ground fog to develop.

Tomorrow, winds shift to become south/southwesterly. With WAA
ramping up, temperatures will be slightly warmer Sunday afternoon
with highs in the mid to upper 80s. Better moisture transport will
lag until Monday, so while it won`t be as oppressively humid as
this past week, dewpoints will steadily increase to near 70
degrees tomorrow. It will be a bit more humid, but heat indices
should remain below Heat Advisory criteria. An isolated storm or
two is possible tomorrow evening as a warm front lifts
northward, (especially south of US 24, but chances are very low
(20% or less)).

The best chances for rain/storms in the next week arrive on Monday,
especially in the afternoon and evening. A mid-level trough will
pivot through and at the surface, a cold front will likely bring
numerous showers and storms to the area. Some storms could be strong
to severe. The Storm Prediction Center currently has our area in a
Marginal Risk (level 1 of 5) for Monday. The atmosphere aloft should
become increasingly unstable during the day Monday as dewpoints in
the mid 70s and temperatures in the mid to upper 80s will yield
~2500 J/kg of surface CAPE. It`s possible we get one or two rounds
of storms Monday, although the best environment will be along the
cold front later in the day. Storms may develop Monday late morning/
afternoon out ahead of the front as the trough swings through, but
more storms could also develop Monday evening with the better axis
of lift/shear as the front comes through. This will be something we
will monitor in the coming days.

July will start on a seasonable and dry note as surface high
pressure and an upper level ridge build in by midweek. Tuesday
through Thursday currently looks to be mainly dry, with comfortable
levels of humidity and temperatures near normal! I`m a bit more
uncertain as we head towards the weekend how the forecast will pan
out; some low chances for rain/storms may be possible for the 4th of
July and into the holiday weekend depending on how amplified the
upper level ridge is.


&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 126 PM EDT Sat Jun 28 2025

An area of high pressure slowly moves eastward allowing the area to
be on the western side of it by Sunday, which allows a return of the
humidity with dew points rising back into the 70s. Depending on how
quickly this low level moisture moves in, some fog/br could form,
but the question is how far is it able to get. Given this
uncertainty, have left it out of this taf issuance. Otherwise,
expect VFR conditions as the surface high pressure moves through.
Northwest winds this afternoon remain below 10 kts sustained, but
will become southeast to south winds on Sunday.

&&

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

&&

$$

DISCUSSION...Johnson
AVIATION...Roller