609
FXUS63 KIWX 130544
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
144 AM EDT Thu Jun 13 2024

.KEY MESSAGES...

- Chances severe storms late Thursday & Thursday evening with
  strong gusty winds and large hail.

- Hot & humid Sunday through Wednesday; highs around 90 to 95 with
  afternoon heat indices 95 to possibly as high as 105.

- After Thursday, storms will again be possible during the
  afternoons and evenings Sunday through Wednesday.

&&

.DISCUSSION...
Issued at 1233 PM EDT Wed Jun 12 2024

Surface high pressure stretching the length of the Appalachians will
keep the region mostly dry through tonight. However, a
progressive westerly flow aloft could bring another weak wave
across the northern portion of the forecast area later this
evening with a few showers or storms. Another disturbance will
then move into Michigan around sunrise tomorrow, but is
generally expected to remain north of the area. The bigger
concern is a storm system developing over the great plains that
will move in late tomorrow afternoon and evening. Wind shear
will be favorable for organized linear convection with around 40
kts of bulk shear. Moisture and instability will also be on the
rise with dewpoints in the mid 60s. The highest CAPE will be
across northwest Indiana into southwest Michigan topping 2000
J/kg surface based. CAMs are in decent agreement bringing storms
in from the Northwest as early as 4 PM EDT. SPC keeps a slight
chance of severe storms across this area with the greatest
threats being wind and hail, although cannot rule out a few isolated
tornadoes. The severe threat should end before midnight when
the convection then transitions into more of an MCS with a
marginal risk of excessive rain.

Upper level ridging starts to shift eastward from the plains on
Friday and then builds on Saturday. It will therefore be warm
and dry to start the weekend with highs in the low to mid 80s.
Heat and humidity increases on Sunday and highs will be in the
90s. A shortwave could also bring some storms Sunday afternoon
or evening. Moisture increases further on Monday with southerly
flow, and heat indices will climb to near 100 degrees. Pop-up
afternoon convection will also be possible. Similar conditions
are expected on Tuesday and Wednesday.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 139 AM EDT Thu Jun 13 2024

Predominantly VFR conditions for the TAF period outside of
chances for a line of rain and thunderstorms late this
afternoon into the overnight hours. Expect MVFR, possibly IFR
in any stronger storms. Most of the guidance suggests time of
arrival at around 22-03z for KSBN and 2-6z at KFWA, with a
possible wind shift to the WNW quickly behind the line.
Otherwise, dry conditions return for the latter portion of the
period.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Cobb
AVIATION...MCD