Michigan City, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

806
FXUS63 KIWX 180841
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
341 AM EST Sat Jan 18 2025

.KEY MESSAGES...

- Rain continuies early this morning with perhaps a brief
  changeover to snow. Accumulations will be minimal, if any.
  There may be some slick spots on roads, bridges, and
  overpasses.

- Lake effect snow gets going in southwest Lower Michigan and
  northwest Indiana today and especially on Sunday. A Winter
  Weather Advisory has been issued for Berrien County, MI
  tonight through Sunday.

- An Extreme Cold Watch has been issued from Sunday night
  through midday Wednesday. Dangerous cold begins filtering into
  the area Sunday and lasts into the middle of next week.
  Several nights with lows below zero are anticipated. Wind
  chills as low as 20 to 25 below zero are expected at times.

- Gusty winds of 20 to 30 mph may cause some blowing and
  drifting snow early in the week, especially closer to Lake
  Michigan. Lake effect snow early in the week will be limited
  by the dry, Arctic airmass.

&&

.DISCUSSION...
Issued at 338 AM EST Sat Jan 18 2025

Currently, our area is sandwiched between two areas of low
pressure, with one passing through the northern Great Lakes
region and the other through the Ark-La-Tex region. From these
two systems, an expansive cold front is sweeping across the
central CONUS. With temperatures still in the mid to upper 30s,
precipitation is falling as rain. Previous forecasts has rain
changing to snow, but temperatures have ended up a few degrees
warmer than expected. There still could be a brief changeover to
snow this morning on the backside of the system, but snow
accumulations will be minimal. The best chances for any snow to
accumulate will be along and south of US 24. As temperatures
drop below freezing throughout the morning, there could be some
slick spots on roads, bridges, and overpasses.

Lake effect snow showers will start up behind the cold front
downwind of Lake Michigan. Lake effect snow showers will become
increasingly likely starting later today and lasting through Sunday.
Low level winds converge with a strong north fetch. Lake effect snow
may start off slow given weak Delta Ts and a shallow inversion.
Parameters become more favorable with the most intense lake effect
snow during in the day Sunday as a strong 500 mb shortwave pivots
through the lower Great Lakes. High res model guidance depicts a
single band of lake effect over southwest Lower Michigan and far
northern Indiana on Sunday. While exact placement still has yet
to be determined, locations under the most intense lake effect
snow could see several inches of accumulation. A Winter Weather
Advisory has been issued for Berrien County, MI from 7 PM EST
tonight to 1 AM EST Monday. 3-6" of snow will be possible, with
isolated higher amounts. The Advisory may need to be extended to
surrounding counties as confidence increases on where exactly
the lake effect snow band sets up. Nonetheless, travel impacts
are likely and some blowing snow is possible near Lake Michigan.
As winds switch to become more northwesterly/west into Monday
and dry air moves in, lake effect will diminish across our
forecast area.

A large area of high pressure will allow for bitterly cold
Arctic air to spill into the central CONUS and Midwest starting
as early as Sunday through the middle of next week. Our office`s
very first Extreme Cold Watch has been issued to account for
the dangerously cold wind chills. The Extreme Cold Watch goes
into effect from Sunday night through late Wednesday morning.
Monday and Tuesday will be the coldest days of week with highs
only in the single digits. Widespread lows below zero are
likely from Sunday night to Tuesday night. With wind gusts
between 20 to 25 mph at times, wind chills values will be as low
as -15 to -25 degrees at times from Sunday night through
Wednesday morning. This dangerous cold will be brutal, with
frostbite possible in as little as 30 minutes! Limit prolonged
exposure outdoors and take precautions to protect pets and
exposed pipes from this bitter cold. The last time wind chills
were this cold was December 2022. Temperatures will moderate
towards seasonable levels (but still below freezing) by mid to
late next week.


&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 109 AM EST Sat Jan 18 2025

A pair of upstream short waves will bring continued rain to
terminals during early part of the overnight hours. These short
waves appear to remain unphased which will slow the cold air
intrusion and precipitation type changeover. It still appears as
though 2 to 4 hour period of wet snow is possible at KFWA in the
11Z-15Z timeframe. VFR conditions to begin this period will
deteriorate to MVFR overnight with IFR conditions possible at
KFWA where low level moisture axis will reside. Potential for
LLWS should diminish by the 08Z or 09Z timeframe. The potential
of lake effect snow showers will increase this afternoon, but
especially tonight. However, current indications suggest the
best potential west and northwest of KSBN through the end of
this forecast valid period.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Extreme Cold Watch from late Sunday night through Wednesday
     morning for INZ005>009-012>015-017-018-020-022>027-
     032>034-103-104-116-203-204-216.
OH...Extreme Cold Watch from late Sunday night through Wednesday
     morning for OHZ001-002-004-005-015-016-024-025.
MI...Extreme Cold Watch from late Sunday night through Wednesday
     morning for MIZ078>081-177-277.
     Winter Weather Advisory from 7 PM this evening to 1 AM EST
     Monday for MIZ177-277.
MARINE...Small Craft Advisory until 5 AM EST Tuesday for LMZ043-046.

&&

$$

DISCUSSION...Roller
AVIATION...Johnson