433
FXUS63 KIWX 051823
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
223 PM EDT Thu Jun 5 2025

.KEY MESSAGES...

- Scattered showers and isolated thunderstorms along and east
  of Interstate 69 this afternoon into early this evening.
  Locally heavy rain possible.

- Near normal temperatures and periodic chances for showers
  Friday through early next week.

&&

.DISCUSSION...
Issued at 223 PM EDT Thu Jun 5 2025

High moisture content (pwats near 1.75") and weak instability will
keep scattered showers and isolated storms in the vicinity of a
lingering low level trough along and east of the Interstate 69
corridor this afternoon into early this evening. Nuisance type
ponding of water on roads possible under slow moving, heavier
showers.

Shower coverage should diminish tonight into Friday morning with low
stratus and patchy drizzle/fog in the vicinity of the weak trough
expected to sink slowly southeast. A subtle mid level impulse also
tracks through the area in persistent west-southwest flow aloft
overnight into Friday morning which could aid in generating light
showers, mainly along and southeast of the US 24 corridor. A more
pronounced shortwave looks to take a more southerly route through
the Mid MS and northern OH Valleys late Friday afternoon into Friday
night near the lingering moisture axis. The result is higher
PoPs/QPF favored south of the local area during this time, though
did retain slight chc PoPS in our IN/OH zones given the lingering
boundary layer moisture and close proximity to the upper wave.

Subsidence in wake of the late Friday shortwave is expected to push
the moisture axis well south with weak sfc high pressure briefly
building through the Great Lakes with dry conditions anticipated for
most of Saturday.

Pattern will remain somewhat active Saturday night through Monday.
Shower chances Saturday night into early Sunday will come from the
next shortwave and  in westerly flow, this time taking a track east
through the lower Great Lakes. A cold front then slides through late
Sunday into Sunday night on the leading edge of a large upper level
low diving southeast into the western/northern Great Lakes by
Monday. These features will bring periodic rain chances, though
chances/amounts are limited this time due to lacking deeper moisture
and quick movement. Mainly dry and trending warmer then behind the
upper low for the mid-late week periods.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 112 PM EDT Thu Jun 5 2025

Showers have reentered the airspace at KFWA with the stationary
front currently slicing through northeast IN. I did remove the
TS chance from the existing TAF as the best opportunity for any
TS development appears to be south of the terminal where
instability is better.

Otherwise, generally anticipate copious low-level moisture and
an overall stagnant air mass to allow soupy conditions to linger
at both sites. Time height cross sections shows plenty of
trapped low level moisture. Paired with light wind and on the
heels of 2-3" of rain that fell through this morning, LIFR
conditions appear to be quite likely. This signal is a little
stronger at KFWA (guidance has higher probabilities of LIFR
ceilings) as they are closer to the front, but pattern
recognition suggests KSBN can see LIFR conditions as well. A
gradual improvement is expected late in the TAF period, but
exact timing is low confidence.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Air Quality Alert until midnight EDT /11 PM CDT/ Friday night
     for INZ005>009-012>015-017-018-022>027-032>034-103-104-
     116-203-204-216.
OH...None.
MI...Air Quality Alert until noon EDT Friday for MIZ078>081-177-277.
MARINE...None.

&&

$$

DISCUSSION...Steinwedel
AVIATION...Brown