110
FXUS63 KIWX 030758
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
358 AM EDT Thu Jul 3 2025

.KEY MESSAGES...

- Slight chance (15-20%) for a stray shower or storm this
  afternoon and evening.

- Hot and humid Friday into this weekend.

- Somewhat better chances for showers and storms (40-50%)
  return Sunday into Monday.

&&

.DISCUSSION...
Issued at 358 AM EDT Thu Jul 3 2025

The region will continue to be impacted by weak disturbances
into this evening with upper level heights slowly building
overnight into the start of the weekend. As noted this past
evening, a moderately unstable environment will be in place with
MLCAPE in the 1000 to 1500 J/KG range along with steep low level
lapse rates and inverted V soundings (DCAPE 900-1200 J/KG). A
lack of clear triggers will result in another day of very
isolated convective development that can form on any boundaries
(lake breeze or remnant outflows from evening convection) or
that move in from upstream. No more than slgt chc pops are
warranted at this point mainly in the 20 to 24Z time frame.
HRRR, which handled the evening scenario, does suggest some
convection could persist in SW areas through 3 or 4Z but for now
have not extended pops.

As noted, upper level ridging will expand northeast Fri into
Saturday with afternoon highs reaching their peak with highs
likely into the 90s. Some signals exist in a few models that
mixing of slightly lower dewpoints could occur each afternoon
that would subsequently limit impacts from heat indices, but
could also allow highs in some areas to overachieve. Have kept
status quo for now and defer to later shifts to watch trends.

The next trough will begin to edge in for Sunday and Monday
bringing somewhat better chances for showers and storms. Model
blends have backed off from likely pops as overall setup is
similar to earlier this week with what will probably be limited
coverage for the area and some seeing little rainfall.

Temperatures trend back down somewhat for next week with highs
back into the low to mid 80s and somewhat lower dewpoints with
the NW flow re-establishing as well as a series of weak
disturbances to bring periodic, diurnal chances for
showers/storms.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 123 AM EDT Thu Jul 3 2025

VFR conditions will prevail through this TAF period. Light and
mainly variable winds overnight periods but light diurnal winds
become north-northwesterly during the day. Diurnal cumulus also
will develop aoa 5 kft during the daytime. A low confidence for
an isolated shower/thunderstorm especially for KSBN after 18z
Thu but have opted to leave out of TAF forecast with the large
uncertainty with the mainly pop-up scenario in place.

&&

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

&&

$$

DISCUSSION...Fisher
AVIATION...Andersen