435
FXUS63 KIWX 091032
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
632 AM EDT Wed Jul 9 2025

.KEY MESSAGES...

- Becoming hot and humid Friday and Saturday. Highs in the upper 80s
  with heat indices in the low to mid 90s.

- Chances abound for mainly afternoon and evening showers and
  thunderstorms through early next week.

- Severe storms are not expected.

&&

.DISCUSSION...
Issued at 258 AM EDT Wed Jul 9 2025

Incredibly stable mid level (700mb-500mb) lapse rates in the
order of 4.7 to 5.0 C/Kg were over northern Indiana and
surrounding areas. Scattered showers and a few storms have
survived the night in the base of the upper level trof that was
moving through the Upper Great Lakes region. Scattered showers
and storms will become more numerous by late this afternoon with
daytime heating. Severe storms are not expected, but locally
heavy rainfall and wind gusts up to 40 mph will be possible.
There should be a short break in the activity Thursday with
somewhat more stable air, slightly lower dew points and weak
subsidence.

An upper level trof topping the subtropical ridge extension was
over the southwest CONUS will phase with another wave moving
east across southern Canada. These merging systems will bring a
good chance for showers and storms Friday. Given the stable
conditions, heavy rainfall is not expected. After Friday,
numerous chances for showers and storms will persist through the
middle of next week given the environment of high precipitable
water values and deep moisture.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 630 AM EDT Wed Jul 9 2025

A lead mid/upper level trough will continue to track across
northern Indiana this morning and appears to have an MCV feature
associated with it. Showers have increased in coverage over the
past hour or two across west central Indiana along the southern
periphery of this feature. Eastward track of this vort max
could provide a brief window of shower potential mid morning
through midday at KFWA. Some brief vsby restrictions are
possible at KSBN early this morning as departure of greater
coverage mid cloud deck could allow for some patchy fog to
develop through 13Z.

A larger scale upper trough will settle across the Great Lakes
today allowing a cool front to drop southeast across the region.
This should allow for scattered thunderstorm development this
afternoon across northern Indiana with best chances at KFWA
given frontal progression. Rain showers should diminish this
evening as frontal boundary becomes more diffuse. Guidance does
depict some potential of some patchy shallow fog just in wake of
this sfc trough where near surface vertical moisture profiles
may be a bit more supportive before drier air works in from the
west. Did include MVFR vsby mention at KFWA with the 12Z TAFs to
give some indication of this potential late this period.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Beach Hazards Statement from 4 PM CDT this afternoon through
     late tonight for INZ103.
OH...None.
MI...Beach Hazards Statement from 5 PM EDT this afternoon through
     late tonight for MIZ177-277.
MARINE...None.

&&

$$

DISCUSSION...Skipper
AVIATION...Marsili