Area Forecast Discussion
Issued by NWS Northern Indiana

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635
FXUS63 KIWX 021816 CCA
AFDIWX

Area Forecast Discussion...CORRECTED
National Weather Service Northern Indiana
209 PM EDT Tue Sep 2 2025

.KEY MESSAGES...

- One more warm day Wednesday with highs near 80.

- A strong cold front will bring showers and isolated thunderstorms
Wednesday afternoon into Wednesday night. Some showers will linger
over northwest Ohio Thursday morning.

- Highs only in the 60s to around 70 are expected Thursday through
Saturday.

- There is a Moderate Swim Risk for Lake Michigan Beaches in Berrien
County, MI on Wednesday. There is a High Swim Risk for both La Porte
County, IN and Berrien County, MI on Thursday.

&&

.DISCUSSION...
Issued at 158 PM EDT Tue Sep 2 2025

Weakening surface high pressure was over the region accompanied by
light winds and clear skies. The dry conditions and low humidities
and some drought feedback have been allowing night temperatures
to fall into the 50s over many areas with even some mid 40s over
locally colder locations. Increasing clouds will allow milder
temperatures tonight ahead of the next system that will bring
rain tonight.

A composite of the latest models favor rain in a 24 hour window
from Wednesday at 18Z (2pm EDT) to Thursday at 18Z (2pm EDT).
Relatively weak dynamics and limited moisture will prevent
storms from becoming severe. Rainfall amounts are forecast to be
from a half an inch to around an inch.

A substantial negative height anomaly near 400 meters will persist
from basically the Upper Great Lakes region to near the south end of
Hudson Bay near James Bay until late Saturday. This system, likely
aided by more drought feedback, will bring chilly temperatures
with lows down into the 40s to from Thursday night through
Saturday night.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 200 PM EDT Tue Sep 2 2025

A large ridge of high pressure from the western Great Lakes to
southeast Canada will continue to provide a weak gradient and light
winds across northern Indiana tonight. An upper level low across
south central Canada will sink southeast late tonight into Wednesday
with an accompanying sfc low pressure area deepening across SE
Ontario during the day Wednesday. This will provide some stronger
southwesterly gradient and decent mixing profiles should support
some southwest wind gusts to around 15 knots at KSBN during the day
Wednesday. Moisture quality will be limited ahead of the front and
won`t improve substantially until near the immediate frontal zone
with some better pooling of moisture. Greater rain chances should
hold off at KSBN until after this forecast valid period, and likely
just behind the sfc cold front.

&&

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

&&

$$

DISCUSSION...Skipper
AVIATION...Marsili