River Flood Warning 55, NWS Northern Indiana

Area Forecast Discussion
National Weather Service Northern Indiana
929 AM EDT Wed Sep 16 2026

.KEY MESSAGES...

- Humid with rounds of showers and thunderstorms through
  Thursday, best chances this morning, and then again later
  tonight into Thursday morning (50-80%).

- Locally heavy rainfall and flooding possible today into Thursday.

- Dry and less humid conditions on Friday followed by renewed
  opportunties for rain and storms this weekend.

&&

.UPDATE...
Issued at 929 AM EDT Wed Sep 16 2026

Larger area of rain, with embedded thunderstorms along the
leading edge, continues to work slowly ENE across the area in
association with a MCV moving east. Pockets of 1 to locally 3
inches of rain are scattered about the area with the most
prominent swath of heavy rain from NE Grant county into
southern portions of Wells and Adams county with a CoCoRaHS
report of 3.82 inches near Linn Grove. Will need to monitor
where the heavier cells track with some potential need for hydro
warnings in these area. Did increase pops to categorical and
progress it along with most likely a slow weakening trend.
Severe weather is not expected.

In the wake of this MCV, we should see somewhat more stable
conditions move in which will limit, not eliminate additional
shower/storm chances. SPC Day 1 outlook has expanded the
Marginal Risk for Severe Storms towards the west (roughly Mario
to Continental OH line east). Not sure this will come to
fruition, but if pockets of clearing can occur then a wind
threat similar to yesterday may evolve.

&&

.DISCUSSION...
Issued at 207 AM EDT Wed Sep 16 2026

A frontal boundary and ~2 inch PWAT axis will hover in west to
east fashion over the area through at least Thursday with
periodic shower/storm chances. Locally heavy rainfall/flash
flooding will be the primary concern given the high moisture
content and potential for several rounds of slow moving
convection.

Favorable right entrance region upper support, in conjunction
with an incoming convectively augmented mid level impulse
(potential MCV), should keep at least scattered convection in
the vicinity of the theta-e ridge this morning, especially
across northern IN and northwest OH. Rainfall rates have been
impressive (over an inch in 10-15 minutes), so will continue to
monitor flooding going forward.

Weak height rises on the northern fringes of a stout upper level
ridge suggest some overall subsidence this afternoon into this
evening. Held with lower PoPs as a result during this time, but
still cannot rule out widely scattered convection within any pockets
of greater heating, mainly near the US 24 corridor. Later tonight
into Thursday morning then features increasing chances for
another round of storms and potential hydro issues as renewed
warm advection ensues within another low level jet.

The bulk of available model guidance does push the effective frontal
zone off to south-southwest by Thursday night into Friday with brief
dry and less humid conditions. Rain/storm chances then return
this weekend as piecemeal shortwave energy ejects east out of
the Intermountain West, forcing the boundary and instability
axis back north into the lower Great Lakes.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 536 AM EDT Wed Sep 16 2026

Smaller scale, convectively enhanced, mid level impulses will drive
waves of convection through northern IN this morning. This
activity will remain along and north of a frontal zone
stalled out over the area. High moisture content will continue
to induce locally heavy rainfall rates and brief times of
LIFR/IFR visby's, especially in and around KFWA. Coverage of
rain and embedded storms should wane this afternoon with MVFR to
low VFR stratocu likely filling in.

&&

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

&&

UPDATE...Fisher
DISCUSSION...Steinwedel
AVIATION...Steinwedel

Preliminary Local Storm Report
National Weather Service Northern Indiana
846 AM EDT Wed Sep 16 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0730 AM     Flood            3 ESE Geneva            40.58N 84.91W
09/16/2026                   Adams              IN   Public

            Emergency management relayed a public report
            of a flooded road. The road was CR 125 E,
            between 1175S and 1200 S near the Wabash
            River.

&&

LWF

Preliminary Local Storm Report
National Weather Service Northern Indiana
953 AM EDT Wed Sep 16 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1030 PM     Tstm Wnd Dmg     Hillsdale               41.93N 84.64W
09/15/2026                   Hillsdale          MI   Emergency Mngr

            Delayed report of a few trees downed and a
            few power lines downed in Hillsdale, MI.
            Time estimated from radar.

&&

NDM

Preliminary Local Storm Report
National Weather Service Northern Indiana
1008 AM EDT Wed Sep 16 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0445 AM     Flash Flood      3 E Berne               40.65N 84.90W
09/16/2026                   Adams              IN   Emergency Mngr

            Delayed report of road closure at CR 200 E
            between SR 218 and CR 650 S.

0445 AM     Flash Flood      3 ENE Berne             40.67N 84.90W
09/16/2026                   Adams              IN   Emergency Mngr

            Delayed report of road closure at CR 200 E
            between SR 218 and CR 500 S.

&&

Preliminary Local Storm Report
National Weather Service Northern Indiana
1020 AM EDT Wed Sep 16 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 PM     Tstm Wnd Gst     1 SSE Bear Lake         41.30N 85.51W
09/15/2026  M83 MPH          Noble              IN   Amateur Radio

            Delayed report of several trees and power
            lines downed on 475 West. Measured gust to
            83 mph.

&&

NDM

Preliminary Local Storm Report
National Weather Service Northern Indiana
1021 AM EDT Wed Sep 16 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 PM     Hail             1 SSE Bear Lake         41.30N 85.51W
09/15/2026  E1.00 Inch       Noble              IN   Amateur Radio

            Delayed report of hail ranging from dime to
            quarter sized on 475 W.

&&

NDM