386
FXUS63 KIWX 260018
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
818 PM EDT Tue Jun 25 2024

.KEY MESSAGES...

- Uncertainties with storm redevelopment tonight.

- Hot weather not expected through the weekend. High will be
  mainly in the upper 70s to mid 80s.

- Next system is expected to bring chances for rain & storms
  late Friday into early Saturday night.

&&

.DISCUSSION...
Issued at 252 PM EDT Tue Jun 25 2024

The initial round of storms has moved south along the outflow
boundary where convection was becoming more scattered. Large CAPE
values were indicated by SPC mesoanalysis from around 4000 to
5000 J/Kg south of the boundary from east central IL to west
central IN. Massive hail cores were indicated in this area with
70 dBz to over 30K feet per radar.

West of the forecast area over nrn IL and far southern WI, an
EML was helping to produce extremely large CAPEs in a long band
of >6000 J/Kg and a core over 6500 J/kg per SPC. Capping at the
base of the EML should hold storms in check until late this
afternoon and this evening per HRRR. Have reduced storm
coverage over the forecast area into early this evening given
the above reasoning. It still looks like a more marginal storm
threat tonight, although locally heavy rainfall is possible
along with possible subsequent flooding of mainly urban area.

Otherwise, a break in the stormy weather is expected until late
Friday when a pair of upper level systems are forecast to reach
the area per GFS. BUFKIT soundings given a strong signal for the
potential for heavy rain with precipitable. water values over
2.0 inches.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 746 PM EDT Tue Jun 25 2024

The cap has broken at the base of the EML to the west. Rather
explosive storm growth has been occurring where substantial
CAPEs were still over 4000 J/Kg. However, massive stabilization
farther east was making it difficult for storms to move east. It
looks like some upper level support later tonight will allow
storms to eventually reach the area and FWA and SBN terminals.
Have updated TAFs in this regard with a later arrival time.
There is still low confidence in this timing and further updates
are likely to be needed.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Beach Hazards Statement until 7 PM CDT this evening for INZ103.
OH...None.
MI...Beach Hazards Statement until 8 PM EDT this evening for MIZ177-
     277.
MARINE...Small Craft Advisory until 8 PM EDT this evening for LMZ043-
     046.

&&

$$

DISCUSSION...Skipper
AVIATION...Skipper