182
FXUS63 KIWX 110524
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
124 AM EDT Thu Jun 11 2026

.KEY MESSAGES...

- High temperatures around 90 degrees coupled with humid
  conditions are expected again Thursday. It is possible another
  heat advisory will be issued for portions, if not all, of the
  area. If venturing outside, be sure to take breaks and stay
  hydrated.

- Chances for severe weather exist tonight and again Thursday
  night. Damaging wind, hail, heavy rain, and a tornado or two
  are possible for both severe weather threats.

- Next chances for showers and storms return Saturday night with
  another cool frontal passage, bringing cooler temperatures
  into low/mid 70s to lower 80s along with decreased humidity
  across the area Sunday into the middle of next week.

&&

.UPDATE...
Issued at 741 PM EDT Wed Jun 10 2026

Outflow dominant line of weakening convection now just west of
the Interstate 69 corridor will continue east toward northwest
OH over the next several hours. Gusts with the outflow have
generally be up to 40-50 mph, though a few 55 mph plus gusts
have been measured with more pronounced isolated cells along the
composite outflow. Some isolated wind damage will remain
possible with this line, though a gradual weakening trend
remains possible as this activity continues to outrun better
mid-upper level forcing/shear. Forecast remains on track
otherwise with the second round after midnight likely not nearly
as formidable as this first round has worked over the air mass.

&&

.DISCUSSION...
Issued at 242 PM EDT Wed Jun 10 2026

Hot and humid today which will help to set up a couple more
bouts of rain and storms later today with another shortwave
rippling through the westerly flow aloft supplying a lifting
mechanism which will come in two parts. The first part will come
into the western parts of the CWA around 6 PM EDT and quickly
push eastward through the rest of the area. This will be
followed by a second impulse around Midnight EDT. Storms with
may be strong with even a few becoming severe. The limiting
factor will once again be the lower amount of shear available,
bulk shear values of 20 to 30 kts will be present so some storms
may exhibit organization. Current radar imagery has a linear
MCS pushing eastward across western IL/WI attm. Current thinking
is that the better forcing/energy with the first impulse pushes
northeastward and will stay north of the area with a weaker line
pushing across the area. Expectations for the second bout
pushing through late tonight should generally be weaker than the
first with less than ideal diurnal timing. However, main impacts
for both sets tonight will be gusty winds and moderate to heavy
rainfall. A tornado or two cannot be ruled out. SPC has our
area currently under a slight risk for severe storms.

Tomorrow we will once again see the hot/humid conditions with
dew points and temperatures slightly less than what we saw
today. Will decide overnight on if another heat advisory may be
needed. As said yesterday, either way it will be uncomfortable
especially since we have not had much of this heat/humidity
prior to this week. This continued heat and humidity on Thursday
will set the table for another chance at severe weather late on
Thursday. This looks generally a better set-up for organized
storms as the main focus for the storms will be a cold front
associated with a low pressure circulation pushing northeastward
through southern WI. The cold front will push eastward into the
western portions of the CWA late in the evening tomorrow with
current timing looking right around 10 PM EDT. This frontal
boundary will also allow for better lifting mechanism and a
better shear profile. Low level shear around 40 to 50 kts and
helicity values around 250-300 m2/s2. Also some of the forecast profile
data has effective layer STP values around 4 to 5. The thinking
is this will be a linear convective system along the boundary
with the potential for QLCS type spin ups especially for the
western portions and northern half of the CWA. So will need to
really watch this system and definitely looks interesting. SPC
currently has a portion of our area in an enhanced risk for
severe weather. All threats look to be on the table with this
event including tornadoes.

Cooler and drier airmass will push in behind the cold frontal
boundary on Friday. Highs on Friday and Saturday will range from
the upper 70s to mid 80s. Looking like a nice couple of spring
days on Friday and Saturday with mostly sunny skies in store.
Another cool front will approach the area late Saturday into
Sunday morning and bring another batch of showers and
thunderstorms with storms at this time not expected to become
severe. The front will bring a cooler airmass into the area with
high temperatures on Sunday afternoon through the middle of
next week in the 70s. A shortwave moving through a zonal flow
aloft will bring a small chance of showers with perhaps a rumble
of thunder or two late Monday into Tuesday morning. A trough
looks to set up over the Great Lakes region and will bring
periods of showers to the area on Tuesday and Wednesday.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 741 PM EDT Wed Jun 10 2026

Another warm and humid day that starts with a thermal boundary
around the area. There`s some question about when it lifts northward
and, as there was this morning, that could produce a brief period of
adverse flight conditions as it does so, but don`t have enough
confidence to include it in these tafs. Otherwise, we`ll be waiting
until likely after 00z for our chance for thunderstorms to arrive to
the area. These look to be intense with enough moisture in the
atmospheric column to produce IFR conditions or worse so will put
that into a prevailing group as confidence is at least medium
that it comes through. This is expected to have damaging wind
with it and may have embedded tornadic circulations. This moves
through the area by 7 or 8z. Drier conditions follow this system
for Friday. We`ll also have some gusty winds to 25 kts ahead of
the line this afternoon.

&&

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

&&

$$

UPDATE...Steinwedel
DISCUSSION...Andersen
AVIATION...Roller