364
FXUS63 KIWX 292322
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
722 PM EDT Sat Jun 29 2024

.KEY MESSAGES...

- Scattered showers and thunderstorms this afternoon. A few
  storms may become severe. Strong to locally damaging winds and
  heavy rainfall will be the main threats.

- Dry, cooler & less humid Sunday and Monday. Highs in the 70s.

- Very warm Tuesday through Thursday (July 4th) with highs in the
80s to around 90. Chances for showers and storms each day.

&&

.DISCUSSION...
Issued at 358 PM EDT Sat Jun 29 2024

Very warm and moist airmass in place today. Instability is
definitely not lacking with around 5000 j/kg of SB CAPE present.
Dewpoint depressions were small today which allowed for mostly
cloudy conditions across most of the area with a few breaks of
sum peeking in but quickly filling in with the surface warming.
Surface dew points remained in the low to mid 70s for most of
the area. The only issue is some capping and an absence of a
decent lifting mechanism. With the late afternoon though we will
see some of that capping erode and latest CAM models indicating
some initiation of convection over the central parts of the CWA
and then moving southeastward into this evening. Any future
outflow boundaries could also spark further convective
initiation as well. Currently, SPC has removed all mention of
slight risk for our area but we are still in a marginal risk
over the entire CWA. Effective bulk shear values of 30 to 40
knots will be present later today and that could help any storms
that do develop to become organized. Storm relative helicity
values will be less than 100 m2/s2 so will make tornado chances
very low. However, with precipitable water values above 1.5
inches to around 2 inches, heavy rainfall will accompany these
storms. Some localized nuisance flooding will be possible with
these storms. Gusty winds with the additional precipitation
loading will also be possible.

As any of the storms that have developed move southeastward
through the evening a drier and cooler airmass will move into
the area in it`s wake with northwesterly flow aloft on the
northeastern periphery of a broad ridge moving easterly over the
southern CONUS. Decreasing clouds on Sunday with highs only in
the 70s and even the upper 60s with a northwest wind bringing
cooler temperatures from over Lake Michigan inland to near shore
areas south and southeast of the lake. Winds will also be on
the increase with gusts around 25 mph or so possible for Sunday.
The increased winds and the northwesterly fetch will make for
dangerous conditions for the beaches of Lake Michigan. A Beach
Hazard statement will be in effect from 1 AM EDT until late
Sunday night to address this hazard.

Comfortable and drier conditions remain through at least Monday
with high temperatures in the 70s with surface ridging again
moving into the area bringing mostly clear skies and a return to
warmer conditions. Warmer temperatures for the rest of the week
will commence on Tuesday with highs back into the 80s and by
Wednesday which looks to be the warmest day next week with highs
around 90 and along with dew points back into the low 70s will
make it uncomfortable once again. The increase in moisture and
temperatures will also make for periods of increased chances of
showers and thunderstorms beginning Tuesday evening and through
Friday.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 722 PM EDT Sat Jun 29 2024

A chance for showers and thunderstorms could be ongoing during the
first few hours of this forecast period around FWA, but otherwise
expect VFR conditions until around 9z or so. Around that point, we
could see some development of MVFR CIGs in the SBN area and maybe at
FWA as well, but there`s less confidence in that occurring there.
Expect that to moderate during the mid morning time frame back into
VFR conditions. Winds are expected to veer more northerly after
starting out of the southwest and will acquire some gustiness
between 20 and 25 kts as early as the morning hours on Saturday.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Beach Hazards Statement from midnight CDT tonight through late
     Sunday night for INZ103.
OH...None.
MI...Beach Hazards Statement from 1 AM EDT Sunday through late
     Sunday night for MIZ177-277.
MARINE...Small Craft Advisory from 1 AM Sunday to 5 AM EDT Monday for
     LMZ043-046.

&&

$$

DISCUSSION...Andersen
AVIATION...Roller