FXUS63 KIWX 161752
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
152 PM EDT Thu Apr 16 2026

.KEY MESSAGES...

- Widely scattered showers and thunderstorms this afternoon, mainly
  along and north of US 30.

- Areas of fog possible late tonight into early Friday, especially
  near Lake Michigan.

- Unseasonably warm on Friday with highs near 80 degrees.

- A round of showers and thunderstorms track through Friday night
  into Saturday morning. A few storms could become severe with
  damaging winds the primary threat.

- Cooler air arrives Saturday night into early next week. This
  may bring frost and freeze concerns, especially early Monday
  morning.

&&

.DISCUSSION...
Issued at 152 PM EDT Thu Apr 16 2026

Cold pocket aloft with a dampening upper wave and near 60F sfc
dewpoints promoting some weak lift/instability this afternoon
for widely scattered showers and thunderstorms. A lake breeze
making slow inland penetration will likely provide an additional
focus with best chances (30-50%) for measurable rain north of
the US 30 corridor. Deeper moisture exiting east will limit
coverage a bit with stronger cells potentially containing small
hail and 30-50 mph wind gusts. Shortwave ridging then follows in
tonight into Friday morning with the potential for fog given
residual sfc moisture, light winds and clearing skies.

Return flow and ample sunshine in advance of the next system will
make for an unseasonably warm Friday with highs near 80. Another
round of convection then becomes the concern Friday night into
Saturday morning as a more pronounced upper trough and strong cold
front track through. Robust upstream convective initiation will
be back toward the Mid/Upper MS Valleys late Friday afternoon,
likely congealing into a linear segment/QLCS with eastward
progression Friday evening. The unfavorable diurnal timing and
resulting lesser CAPE should favor a gradual weakening trend as
this moves west to east through the area late Friday evening
into early Saturday. However, will still have to monitor for
damaging winds given favorable shear/flow profiles and low 60F
sfc dewpoints, especially west of Interstate 69. Showers then
likely linger along the frontal boundary and associated corridor
of deeper moisture Saturday morning, with cooler and drier
conditions likely for the second half of the day through early
next week post-frontal.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 142 PM EDT Thu Apr 16 2026

The upper trof and associated sfc low are translating across
the Gtlks region this aftn and evening. While the deeper
moisture has shifted east, sctd showers have developed over ne
IL and far nw IN ahead of the sfc trof. Have included the
mention of tsra at KSBN for the first few hours of the terminal
fcst.

As the trof settles into the region, winds diminish, and
residual moisture trapped beneath a rather strong llvl inversion
expect cigs to lower and vsby drop to one mile or lower for
both sites. Conditions should improve within a couple of hours
after sunrise.

&&

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

&&

$$

DISCUSSION...Steinwedel
AVIATION...Frazier