224
FXUS63 KIWX 040516
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
116 AM EDT Mon Aug 4 2025

.KEY MESSAGES...

- There is a slight chance (20%) for isolated afternoon showers and
storms for areas mainly south of US 30 on Tuesday, and along and
south of US 24 on Wednesday.

- Very warm and humid conditions may develop next weekend.

&&

.DISCUSSION...
Issued at 209 PM EDT Sun Aug 3 2025

Expansive high pressure over the Great Lakes will weaken and shift
off to the east into Monday and Tuesday with a gradual warming trend
anticipated. The stable and dry air mass associated with this
feature should hold strong through at least tonight and Monday with
pleasant weather (outside of some areas of smoke/haze) persisting.

Moisture will begin to stream northward into at least southern
portions of the forecast area by Tuesday and Wednesday near a weak
inverted sfc trough as a disjointed mid level trough tracks east
into the Mid MS and western OH Valleys. This weak forcing and
developing instability could be enough to generate some diurnally
driven (isolated) showers/storms near this inverted trough, best
chances (still only 10-20%) south of US 30 Tuesday afternoon, and
mainly along and south of US 24 Wednesday afternoon. Typical heat
and humidity for early August otherwise for these periods.

For late this week and next weekend, upper ridging looks to become
reestablished within a blocky pattern setting up a return to hot and
humid conditions.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 111 AM EDT Mon Aug 4 2025

High pressure remains in place over the Great Lakes, though is
now centered over Lake Huron. High, thin cirrus is streaming in
from a weak low swirling over the mid-Mississippi valley.
Scattered thunderstorms are possible within the state but this
activity will stay south of the terminals. Dew points are
awfully dry anyway. Perhaps a few wind gusts this afternoon near
15kts as mentioned in the previous discussion.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...Air Quality Alert until midnight EDT tonight for MIZ078>081-
     177-277.
MARINE...None.

&&

$$

DISCUSSION...Steinwedel
AVIATION...Brown