Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 041024
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
624 AM EDT Fri Jul 4 2025

.KEY MESSAGES...

- Today through Sunday - highs around 90 with heat indices
  around 90 to the mid 90s.

- Isolated mainly afternoon and evening thunderstorms today. Dry
  Saturday.

- Periodic chances for thunderstorms Sunday through Friday.

&&

.DISCUSSION...
Issued at 220 AM EDT Fri Jul 4 2025

Relatively hot and humid conditions are ahead for all three days of
the extended holiday weekend as upper level ridging attempts to
become established across the Ohio Valley region. High temperatures
all three days over the forecast area will be around 90 into the
lower 90s with heat indices reaching the mid 90s - but below heat
advisory criteria. Temperatures should not be as warm Tuesday
through next Friday with highs near 85 degrees. Along with the
heat, there will be chances for thunderstorms each day through
this upcoming 7 days - except for Saturday.

As for these storms, weak impulses topping the upstream ridge and
moving southeast across the Upper Midwest have the best chance for
reaching the forecast area. Diurnal storms should remain isolated
in the 19Z to 01Z window. Severe storms are not expected given very
stable mid level lapse rates near 5.0C/Km.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 619 AM EDT Fri Jul 4 2025

VFR conditions expected through this TAF period with mainly
light and variable winds with a slight uptick with diurnal
warming after 15z today. Convection that originally developed
over northern and central WI continues to move southward and is
now moving through Chicago Suburbs. Expectation is that activity
will fizzle out over Lake Michigan and before moving into either
TAF site. However, still very uncertain whether or not any of
the cells will survive and still have left mention out of the
TAFs. Will continue to monitor these storms and update the TAF
forecasts if current thinking changes.


&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Air Quality Alert until midnight EDT tonight for INZ020.
OH...None.
MI...Air Quality Alert until midnight EDT tonight for MIZ177-277.
MARINE...None.

&&

$$

DISCUSSION...Skipper
AVIATION...Andersen