541
FXUS63 KIWX 070529
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
129 AM EDT Mon Jul 7 2025

.KEY MESSAGES...

- Scattered showers and storms this evening will be capable of
  localized flooding and gusty winds.

- There is a risk for dangerous currents and breaking waves on
  Lake Michigan beaches along the coasts of Berrien and La Porte
  counties this evening into Monday.

- Trending mainly dry and less humid into Monday and Tuesday.
  Shower and storm potential returns mid-late week, best chances
  (30-50%) during the afternoon hours.

&&

.DISCUSSION...
Issued at 131 PM EDT Sun Jul 6 2025

Shower and thunderstorm coverage will increase through the mid-
late afternoon hours along a cold front and leading pre-frontal
trough. Cells will generally be rather pulsy given a muted wind
field resulting in only ~20 knots of effective bulk shear.
Skinny MLCAPE near ~1500 j/kg, and a moist column (precipitable
water values near 2"), may still be enough to encourage
isolated, marginally severe, wind gusts within any deeper
updrafts and/or cell mergers/segments. Torrential downpours and
localized flooding likely the greater threat however given slow
movement, a deep/moist warm cloud layer, and the potential for
backbuilding per small MBE vectors.

Tonight will feature a decline in coverage and intensity of
convection as the the primary front slowly sags southeast through
the area and begins to wash out, though did retain lower end PoPs
through the night given the lingering moisture and modest
instability in the vicinity of the front.

A trend toward less humid and mainly dry conditions Monday afternoon
into Tuesday as we see brief influence from sfc high pressure
skating by to the north. Where exactly the instability axis lays out
by peak Monday remains somewhat uncertain, thus have retained low-
mid chances for widely scattered convection south of the US 24
corridor per a model consensus.

A typical, quasi-zonal flow, pattern will bring daily shower/storm
chances back into the fold mid week through the upcoming weekend,
best chances in the afternoon as several convectively-augmented
waves track through and interact with a frontal boundary oscillating
between the lower Great Lakes and Ohio Valley. Confidence is low
regarding daily PoPs in this regime given the reliance on difficult
to predict smaller scale perturbations. Temperatures should average
out near to slightly above normal otherwise during this time.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 120 AM EDT Mon Jul 7 2025

Through the overnight period Cigs will start out IFR and will
see some slight improvement after 15z Mon for both sites to MVFR
category Cigs with the cool front moving through the area. A few
scattered light showers will be possible over the next several
hours but will come to an end as the front moves further south
and eastward. Winds have shifted to more north to northwesterly
in the wake of the cool frontal boundary passage and will
become more northerly and have become light and should remain so
through the remainder of the TAF period. For KSBN, VFR
conditions should return after about 22z Mon and around 04z Tue
for KFWA.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Beach Hazards Statement through this evening for INZ103.
OH...None.
MI...Beach Hazards Statement through this evening for MIZ177-277.
MARINE...Small Craft Advisory until 9 AM EDT this morning for LMZ043.
     Small Craft Advisory until 11 AM EDT this morning for LMZ046.

&&

$$

DISCUSSION...Steinwedel
AVIATION...Andersen