202
FXUS63 KIWX 021736
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
1236 PM EST Tue Dec 2 2025

.KEY MESSAGES...

- Some lake effect snow showers through early afternoon, but
  additional snow accumulations should be light.

- A strong cold front pushes across the area on Wednesday and
  will likely be accompanied by some light snow accumulations of
  around an inch.

- Much colder air moves in for middle of the week with lows near
  0 by Thursday night and wind chills as cold as 10 below. Some
  moderation in temperatures for the weekend, but still below
  normal.

&&

.DISCUSSION...
Issued at 352 AM EST Tue Dec 2 2025

For tonight center of low level anticyclone will track of the area
with return southerly flow developing overnight. Some hires guidance
is picking up on a fog potential in this setup with return flow over
fresh snowpack. If low clouds can scatter this evening, radiative
processes may help fog form initially also. However, some potential
with strong lingering low level inversion that low clouds could
linger or re-form. This appears to be a muddled combination of
radiative/advective processes over time tonight, but have included
mention of some patchy fog across most areas this evening/overnight.

After brief warm advection shot late tonight into early Wednesday, a
strong cold front will make its way across the area on Wednesday as
broad upper PV anomaly shifts across Hudson Bay/Ontario. Strongest
upper forcing should migrate north/northeast of local area, but
glancing blow of forcing with this upper trough and modest low level
fgen forcing should support a band of snow filling in along low
level front. Moisture and duration of deep moisture will be a
limiting factor with just a narrow axis of 3 g/kg 850 mb mixing
ratios in vicinity of the front. A band of light snow with a
potential of one inch accumulations is expected across SW Lower
MI/NW IN, with expectation that frontal forcing will become a little
more washed out with southeast extent as the upper PV anomaly shifts
across southeast Canada. Some lake response possible late Wednesday
night into early Thursday but depth of lake induced instability
appears limited once again.

An expansive low level anticyclone shifts across the region Wed
night into Thu night with coldest mins of the season expected
Thursday night. Temps should rapidly drop off early Thursday evening
before likely becoming more steady late in the night. Lows around
zero look like a good chance for many areas, and potentially sub-
zero for areas with fresh snowpack from the Wednesday system. Subtle
increase in southerly winds toward daybreak Friday should allow for
some 5 to 10 degree below wind chills. Some moderation temperatures
is expected for the weekend but remaining below normal for early
December. The large scale synoptic pattern of west coast ridging and
SE Canadian troughing could provide favorable low level
baroclinicity for potential additional systems to track across the
Mid MS Valley/Great Lakes next weekend and have maintained
broadbrush chance snow PoPs next weekend into early next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1223 PM EST Tue Dec 2 2025

Patchy fog may continue to impact areas near KSBN over the next few
hours, but low ceilings are expected to persist with MVFR/IFR
conditions expected to prevail through much of the TAF period. At
KSBN, ceilings initially near 3k feet AGL are expected to lower to
near 1k feet AGL after 21z, persisting through around 06z before
slowly lifting. MVFR ceilings around 1500 feet AGL will prevail at
KFWA through tonight. Winds at both terminals will remain light.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory from 1 AM Wednesday to 7 PM EST Thursday
     for LMZ043-046.

&&

$$

DISCUSSION...Marsili
AVIATION...Hammer