826
FXUS63 KIWX 251930
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
230 PM EST Tue Nov 25 2025

.KEY MESSAGES...

- Strong westerLy winds will gust 40-50 mph on Wednesday. Remaining
  breezy and chilly on Thanksgiving with gusts to 35 mph.

- Lake effect snow showers are likely Wednesday afternoon
  through Thursday night, mainly along and north of the Indiana
  Toll Road. Reduced visibilities and snow accumulations will
  create difficult travel in spots.

- A period of accumulating wet snow is possible late Saturday
  into Saturday night, best chances (70%) north of US 24.
  Impacts to post-thanksgiving travel possible.

&&

.DISCUSSION...
Issued at 230 PM EST Tue Nov 25 2025

Surface low pressure deepens east-northeast through the northern
Great Lakes tonight into Thursday in response to a robust negatively
tilted upper level wave digging through. This will send a strong
cold front east through the local area later tonight into early
Wednesday (07-12z), accompanied by a narrow line of gusty rain
showers and rapidly falling temperatures. Pressure rises and intense
post-frontal CAA will allow winds to pick up immediately in the
morning, with a tight low level height gradient keeping westerly
winds up through the day on Wednesday. Momentum transfer progs in
model forecast soundings suggest persistent gusts in the 40-50 mph
range on Wednesday. HREF probs for 45 mph or greater or still around
30%, but did opt for a CWA-wide Wind Advisory per collaboration.
This gradient does relax into Thanksgiving, though it will be chilly
and still breezy (gusts 30-35 mph).

The lake effect snow machine will also get going in cold westerly
flow Wednesday afternoon through at least Thursday night, mainly
impacting areas along and north of the Indiana Toll Road. Lake-850
mb temps near 20C with a decent signal for omega and saturation wrt
ice to align in lower portions of the DGZ. However, westerly flow
will be strong, likely limiting parcel residence time and
organization for a higher end LES event in favored wnw flow snow
belts. There likely will be enough snow for reduced visby`s and
impacts to travel however, particularly in southwest Michigan
where a Winter Weather Advisory was issued.

Attention over the weekend will then turn to the next upper level
trough to dig out into the central Plains on Saturday, then making
the turn east-northeast into the Great Lakes by Sunday. A broad area
of strong theta-e advection and isentropic lift will develop within
the a leading low level jet. This along with incoming mid level dcva
and upper diffluence allows an expansive area of precipitation to
blossom in advance of the system sfc trough and developing weak sfc
low. Ptype looks to begin as wet snow for most at some point
Saturday into Saturday evening before mixing with or changing to
rain/drizzle Sunday morning as WAA eventually overwhelms the column.
Ensemble probs from the LREF and NBM are for approximately 70% of
the members dropping 3" or more of snow (10:1 ratio) in nw IN and sw
MI, which drops to near 20% in our far southeast (Lima area).
Definitely a system to keep an eye on given the potential for post-
thanksgiving travel impacts.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1241 PM EST Tue Nov 25 2025

IFR to LIFR conditions to persist at KSBN into this evening with
low end MVFR to IFR conditions at KFWA.

Low clouds and some fog/mist will continue at both sites, with
lowest cigs likely to remain at KSBN closer to the developing
low pressure area. Later tonight, a cold front will arrive and
sweep quickly through both locations with a band of rain showers
accompanying it (locally lower vsbys and cigs possible).
Thereafter, at least MVFR conditions will persist with sustained
winds and wind gusts quickly ramping up by late morning and
lingering into the afternoon. KSBN may see some lake effect
showers near or just outside the current period, but the SW to W
flow should keep most, if not all activity confined north of the
site.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Wind Advisory from 7 AM EST /6 AM CST/ to 7 PM EST /6 PM CST/
     Wednesday for INZ005>009-012>015-017-018-020-022>027-
     032>034-103-104-116-203-204-216.
OH...Wind Advisory from 7 AM to 7 PM EST Wednesday for OHZ001-002-
     004-005-015-016-024-025.
MI...Wind Advisory from 7 AM to 7 PM EST Wednesday for MIZ078>081-
     177-277.
     Winter Weather Advisory from 10 AM Wednesday to 7 AM EST
     Friday for MIZ078-079-177-277.
MARINE...Gale Warning from 4 AM Wednesday to 1 AM EST Friday for LMZ043-
     046.

&&

$$

DISCUSSION...Steinwedel
AVIATION...Fisher