134
FXUS63 KIWX 260527
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
127 AM EDT Sat Sep 26 2026

.KEY MESSAGES...

- This weekend, cool, crisp mornings give way to afternoon
  temperatures in the low-to-mid 70s. Temperatures trend warmer
  into the early work week.

- Dry conditions persist until early Wednesday morning.

- Rain chances take over from the mid work week potentially
  continuing into the weekend. Uncertainty still remains with
  heavy rain/thunderstorm chances.

&&

.DISCUSSION...
Issued at 124 AM EDT Sat Sep 26 2026

A relatively vigorous shortwave continues to sink southward through
the day today doing nothing more than providing a few clouds to the
area. The column is rather dry as surface high pressure noses in
from the north. Still the area looks entrenched on the western side
of a rex block as a strong upper low deepens along the east coast
and a high pressure system sits in southeastern Canada. This block
helps to dampen a wave as it approaches from the west Sunday
night/Monday and this allows dry weather to continue as another
surface high approaches from the west later Monday into Monday
night. Finally, a Pacific wave approaches the Northern Plains and
western Great Lakes between Monday and Tuesday helping to kick the
stalled strong area of low pressure along the east coast out to sea.

This opens to the door to increased moisture as a mid level wave
with its strongest support in the upper jet more in Canada and a
shearing area of vorticity to its south that tries to edge into the
area into Tuesday night. The best columnar moisture swings through
northern and western areas late Tuesday night into early Wednesday
morning. Models currently only have mid 50s to low 60s dew points
moving in during that time, but 850 mb dew points do surpass 10C.
The ECMWF has minimal MUCAPE to work with. This all seems to
indicate issues with moisture working into the region overall and
potentially some issues with dry air choking moisture transport up
and to the surface even with a moisture connection to the Gulf.

After the prior wave moves through into at least the first part of
Wednesday, it appears there`s a bit of a break in rain until the
washed out front from Wednesday moves back northward as a warm front
for Thursday. This front stalls out across the area and serves as a
focus for showers from Thursday into the weekend. Storm potential
will be dependent on the eventual location of the front, as
better instability could stay south of the area. Surface dew
points reach 65F Thursday and Friday The ECMWF has good large
scale ascent across the area Thursday AM as well as parts of
Friday and Saturday. There is still plenty of disagreement
between when a cutoff low in the southwest makes it up here, but
sometime between Friday and Saturday looks likely. If there was
one day that looks like there could be some stronger
thunderstorms, it`s Saturday, but we have a long time to get
there yet.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 124 AM EDT Sat Sep 26 2026

Despite a shortwave sliding southward across the east coast of Lk
MI, plenty of dry air stays entrenched overhead and helps the area
retain VFR conditions. Winds stay out of the northeast and will be
light, staying less than 10 kts sustained.

&&

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

&&

$$

DISCUSSION...Roller
AVIATION...Roller