South Bend, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

560
FXUS63 KIWX 231919
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
219 PM EST Tue Dec 23 2025

.KEY MESSAGES...

- Patchy fog late tonight with lows near 30.

- Rain, and even freezing rain for south central Michigan, is
  expected Wednesday night and Thursday night. Rain lingers
  Friday morning.

- Mild through the rest of this week with highs in the 40s and
  50s. Colder by Sunday and Monday.

&&

.DISCUSSION...
Issued at 213 PM EST Tue Dec 23 2025

Northern Indiana will be the battleground for clashing air masses
these next couple of days as warm fronts come and go. Temperatures
will generally be above normal with chances for rain and even
freezing rain.

Stratus and fog are gradually mixing out this afternoon as cooler
and drier air attempts to seep in from the northwest. Aloft, 850-mb
temperature advection is neutral and surface high pressure nosing in
will create an inversion that will trap any lingering low-level
moisture leading to at least patchy fog overnight. Northwest IN and
southwest MI may be spared with their dew points already in the
upper-30s as of this midday writing. Cloud cover is another
variable that muddies the forecast a bit. Duration of fog
appears to be limited to pre-dawn hours (~3-4 hours) which will
help reduce travel issues from freezing fog. Confidence is low
on the duration and coverage of fog, but enough ingredients are
in place to afford the "patchy fog" mention.

Warm air advection resumes Wednesday as surface high pressure tracks
east and poleward moisture transport occurs on the western fringe of
a Gulf Coast ridge. Weak low pressure by Wednesday night will result
in a chance of rain, and even freezing rain in southern MI. The
source region (mid-Mississippi Valley) for this rain chance is much
better than this morning`s which was polar (i.e., dry) in nature. A
majority of the forecast area will experience rain, but forecast
soundings in southern MI depict a stout low-level warm nose
indicative of a freezing rain risk. Luckily, low temperatures are
forecast to be right near freezing (as opposed to well into the 20s,
for example) which may limit overall impacts. Instead, a greater
likelihood of freezing rain exists Thursday night into early Friday
morning when low temperatures will be in the upper-20s for far south-
central Michigan spreading into far northwest Ohio.

Colder with rain changing to lake effect snow Sunday as a low moves
across the upper Great Lakes. This replaces late-week high
temperatures that were in the 50s to highs near 40 Sunday (in the
west and north) followed by highs in the 20s by Monday.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1235 PM EST Tue Dec 23 2025

Sfc high pressure is slowly building into the great lakes
region this aftn as llvl clouds have been slow to advect out of
ne IN. KFWA should scatter out in the next one to two hours
with both terminal sites VFR through the aftn into the night
hours. west winds will turn more northwest closer to 00Z and
then diminish following sunset. VFR cigs are expected overnight
with a return of MVFR conds at KFWA after 10Z.

&&

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

&&

$$

DISCUSSION...Brown
AVIATION...Frazier