Portage, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

681
FXUS63 KIWX 042321
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
621 PM EST Thu Dec 4 2025

.KEY MESSAGES...

- Very cold low temperatures near zero overnight tonight with
  wind chills of -5 to -15 degrees.

- Patchy freezing fog possible mainly south and west of the
  US-30 and US-31 intersection.

- Light lake effect snow showers late Friday through Saturday
  should total an inch or less accumulation accompanied by few
  if any impacts. Some freezing drizzle may once again mix in.

- Periods of light snow is likely at times Sunday through the
  rest of this upcoming week. The snow may be mixed with rain.
  Some minor impacts are possible.

&&

.DISCUSSION...
Issued at 235 PM EST Thu Dec 4 2025

The main issue for the short term is the very cold air that will
continue to spill into the area tonight into tomorrow morning
with low temperatures dropping into the single digits to near
zero degrees. Light winds will also create wind chills from -5
to -15 degrees. There also is the potential overnight for some
patchy freezing fog to develop for our southwestern portions of
the CWA mainly south and west of the US-30 and US-31
intersection. With the cold temperatures tonight take proper
precautions to keep your pets and livestock safe and wear warm
clothing that minimizes any exposed skin as frostbite would not
take long with the cold temperatures we will see.

Temperatures do moderate fairly quickly tomorrow with a zonal
flow aloft and some slight synoptic warming. Highs will still
only get into the mid 20s tomorrow. A weak shortwave moving
eastward through the westerly flow will bring a bit more warming
on Saturday with highs flirting with the freezing mark. This
disturbance will also bring some snow showers mainly near Lake
Michigan with a bit of lake enhancement but accumulations/impacts
will be minor with snowfall less than 1 inch expected into
Sunday afternoon. Some freezing drizzle will possibly mix in
with the snow showers due to the warmer lake waters modifying
the boundary level. Highs on Sunday will be slightly cooler with
highs in the upper 20s. However, another reinforcing shot of
arctic air will spill in behind this disturbance and lows on
Monday morning will again return to the single digits and fairly
light winds would bring wind chills around -5 degrees. Monday
high temperatures will only get into the upper teens to around
the 20 degree mark. Tuesday morning will also be cold with lows
slightly warmer than on Monday with temperatures around 6 to 10
degrees above zero.

A trough will push eastward through the area beginning late
Monday into Tuesday bringing chances for light snow across the
area. At least a couple inches of snowfall would be possible
with this system. Southerly flow ahead of the system will advect
some warmer temperatures into the area and highs on Tuesday will
get into the lower 30s. Another system will quickly move into
the area in the wake of Tuesday`s disturbance and this system
will originate further south across the Plains and further keep
temperatures around freezing to mid 30s. This will allow for
some rain to mix in with the snowfall.

Thursday a colder airmass will again push into the region in the
wake of the trough passage. Highs on Thursday will be back into
the mid 20s and residual snow showers will be expected.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 620 PM EST Thu Dec 4 2025

Fog and low stratus development are possible at KSBN tonight
given light southerly winds and otherwise clear skies over deep
snowpack. Confidence is not high as some model guidance
maintains VFR conditions but enough guidance is now on board to
introduce a mention in the TAF. Much lower chances at KFWA given
less moisture advection there but it is not entirely out of the
question. Any fog/stratus should exit and dissipate by 13Z with
VFR conditions anticipated during the day Friday.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory from 3 PM Friday to 11 AM EST Saturday
     for LMZ043.
     Small Craft Advisory from 3 PM Friday to 4 AM EST Saturday for
     LMZ046.

&&

$$

DISCUSSION...Andersen
AVIATION...AGD