063
FXUS63 KIWX 250510
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
110 AM EDT Wed Sep 25 2024

.KEY MESSAGES...

* Lake effect rain showers overnight and through Wednesday.

* Isolated showers are possible in the afternoon area-wide.

* Seasonable temperatures and periodic chances for showers late
  this week through early next week.

&&

.DISCUSSION...
Issued at 205 PM EDT Tue Sep 24 2024

Scattered showers and storms remain the main focus this afternoon
into early this evening. As of 18z, there is a ~1008 sfc low just
now entering nw IN with a warm front extending east into nrn IN and
nw OH. These sfc features will continue to lift north toward the MI
border this afternoon in advance an incoming shortwave impulse.
Showers/storms will accompany this system given the ongoing ample
moisture transport within broad isentropic ascent preceding the
shortwave. The main area of interest is still into mainly
eastern portions of the FA where a muddled warm sector is
building in with MLCAPE nearing 1000 j/g under 25-30 knots of
effective bulk shear. SPC Marginal Risk appears reasonable in
this environment with low LCL heights hinting at the low chance
for an isolated weak tornado/landspout, with isolated wind
damage the primary threat. The overall severe threat is limited
by meager lapse rates and lacking heating thanks to cloud cover.

A few showers may linger within the lingering shear axis
tonight, mainly near Lake MI due to some minor lake enhancement.
Kept fog and stratus in the grids otherwise overnight into
early tomorrow given lingering moist low levels and light winds.
The shear axis and/or trailing inverted trough does slowly
slide east through the area on Wednesday. The result is a non-
zero chance for a few showers/drizzle, though the strip away of
moisture in the mid levels and weak forcing in between upper
level systems may preclude isolated light showers from
developing.

Thursday is likely a dry and seasonable day before daily rain
shower chances return Friday through early next week. Tropical
cyclone remnants lifting north from the Gulf of Mexico look to
get absorbed into a leftover closed low over the lower-mid MS
Valley later Thursday through Saturday, before opening slowly
northeast toward the Great Lakes region Sunday into early next
week. The best opportunity for rain locally look to be Saturday
and beyond, though confidence regarding track/evolution of these
merging features is low. Temperatures should be pretty close to
seasonal norms otherwise.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 105 AM EDT Wed Sep 25 2024

Generally stayed close to the existing TAFs for this issuance.
Stratus is blossoming quickly between KSBN and KFWA and this was
captured accordingly in the TAF. Fog is becoming less certain
amid this rapidly developing stratus field which will likely preclude
any fog development at KFWA, while a mid-level cloud deck at
KSBN has most likely squashed the FG potential there.

Forecast cross sections are rather soupy though the day but with
decreased subsidence through time which should allow any
subsidence inversion to ease late-morning. Isolated showers are
anticipated (lake effect or otherwise) but indeed, coverage
will be isolated. Therefore, carried on with the dry TAF for
now.

&&

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

&&

$$

DISCUSSION...Steinwedel
AVIATION...Brown