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000
FXUS63 KIWX 170808
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
408 AM EDT Wed Apr 17 2024

.KEY MESSAGES...

- More storms to redevelop late this morning with large hail and
  damaging winds possible mainly east of I-69. Latest
  indications are coverage will be very limited.

- Showers Thursday night ending early Friday

- Cool and dry weekend with highs mostly in the 50s and lows in
  the 30s. Frost possible at night.

&&

.DISCUSSION...
Issued at 333 AM EDT Wed Apr 17 2024

A pair of upper level systems will bring 2 rounds of showers and
scattered storms to the area today. The initial round was ongoing in
an zone of isentropic lift per 305K GFS surface moving across
northern Indiana and far southern Lower Michigan at this time. SPC
mesoanalysis indicated virtually no instability. South Bend picked
up a quick >0.10" in less then 1 hour. Given the lack of shear and
no instability, do not expect any severe weather from these showers
and storms. However, the 2nd upper level system approaching from the
west will be accompanied by an occluding front. Several parameters
support the chance for severe weather, especially large hail and
damaging winds east of I-69. Bulk shear (0-6km) was already >
70kts from St Louis to Chicago per SPC mesoanalysis. Made some
major updates to lower shower/storm coverage per HRRR. The
latest HRRR favors VERY limited storm coverage today.

Otherwise, one last system will move across the area Thursday
night before cooler air and drier weather arrives for the
weekend. Severe storms should stay southwest and south of the
area given the surface low track. Rainfall amounts should be up
to half an inch and should not have major impacts on renewal of
recent flooding. At this time, frost is likely Saturday night
and Sunday night. The best chances for freezing temperatures are
near and north of the Michigan border.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1259 AM EDT Wed Apr 17 2024

Cutoff occlusion over sw MN will wobble east through the nrn lakes
today as downstream warm sector pinches off. Decaying/residual low
level moisture plume across IL likely to falter supporting any
renewed shower/storm development ahead of weakening sfc cold front
late morning (west) into mid aftn (east) and in light of continued
downward convective trends in most of the cams model suite will drop
mention with this fcst. Primary aviation issue will be strong
gradient gusts from serly this morning veering to wrly by evening
with gusts aoa 30kts likely.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory until 5 AM EDT Thursday for LMZ043-046.

&&

$$

DISCUSSION...Skipper
AVIATION...T