892
FXUS63 KAPX 032029
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
329 PM EST Sat Jan 3 2026

.KEY MESSAGES...

- Snow tonight (synoptic/enhanced to lake convection).

- Widespread accumulating snow Sunday night.

- Midweek precipitation chances??

- Potentially milder end of week but also more unsettled with rain/
  mixed precipitation.

&&

.DISCUSSION... Issued at 217 AM EST Sat Jan 3 2026

Pattern Synopsis/Forecast: Strongly -NAO influenced pattern with
high latitude blocking from Atlantic Canada...across Greenland/
Iceland and into Europe.  Cold air within the western portion of the
block impacting the Great Lakes and New England...but upstream
ridging over the Great Basin/western Canada allowing for a more
Pacific influence to spread into the western/central CONUS.  Split
short wave trough off the west coast of North America.  Northwest
flow aloft across the Great Lakes with a couple of embedded
disturbances...one is crossing the upper Lakes this afternoon with
another over northwest Ontario.  At the surface...high pressure over
Alberta/Saskatchewan ridges southeast into the Midwest...some
lingering lake aggregate troughing over the Great Lakes.

-NAO remains in place but becomes "constricted" as wavelength
narrows with Greenland blocking ridge...allowing -PNA trough along
the west coast to become more influential in flooding the CONUS with
Pacific modified air and a much more zonal look to the pattern by
Monday.  Could be a low amplitude short wave trough across the Great
Lakes in the Wednesday time frame.  Upstream troughing expected to
push inland during the latter half of the week and allow higher
heights to build into the eastern CONUS.

Midwest anticyclone expected to build across the Great Lakes/Ohio
Valley into Sunday...then shift east by Sunday evening.  Resultant
warm advection pattern into Michigan will be accompanied by a weak
short wave trough (but minimal surface reflection) that will zip
across the state Monday morning.  May see a similar evolution in the
Tuesday-Wednesday time frame.  A more amplified pattern in the
offing beyond Wednesday...which will bring both moderating
temperatures to the Great Lakes along with a more significant chance
for precipitation (rain/mixed precipitation).

Primary Forecast Concerns:

Snow tonight (synoptic/enhanced to lake convection): Large area of
radar returns from southern Manitoba southeast into Michigan...with
a couple areas of heavier snowfall tied more closely to the short
wave disturbances dropping southeast. Northwest flow multi-band
convection continues off Lake Superior aided by low level
frontogenesis as sub-zero cold is banked up along the eastern Lake
Superior shoreline.  Some shallow flurries also off Lake Michigan
into parts of northern Lower...though would expect some seeder-
feeder enhancement this afternoon.  Synoptic snowfall expected to
push east quickly this evening as short wave trough departs...but
lake convection will continue and interesting potential off
Whitefish Bay with the likelihood of enhanced convergence given the
thermal gradient with sub-zero cold to the east of Lake Superior.
This could be the genesis of a mutli-lake band that extends across
Lake Huron and eventually into Lake Ontario.  Inversion heights
around 780mb/-19C with cloud depth maximized in the DGZ...so a
favorable environment. The only thing that could limit accumulations
is in the evolution of the band... which may tend to get pushed west
with time during the night and not focus on one area for a long
period.  General 12 hour snowfall totals across Chippewa county of 2-
4 inches tonight (not including what is occurring now)...though if
things set up right 6+ inch amounts are possible adjacent to
Whitefish Bay.  Given the potential for a pretty significant (even
if short lived) snow band...plus adding what is occurring this
afternoon (which is starting to get pretty intense around the
Soo)...easily can justify a Winter Weather Advisory for at least the
western/central Chippewa zones (southeast Chippewa/Drummond Island
will leave out for now). Advisory will start as soon as the forecast
gets out. Multiband convection off Lake Michigan should be a bit
more "generic" but 1-3 more inches should be in the offing for the
higher terrain of northern Lower. And will have to watch single
dominant band expected to develop over Lake Huron later this evening
and should get pretty close to the US-23 corridor from Alpena
northwest to Rogers City.

Widespread accumulating snow Sunday night: Push of deep layer
warm advection... assisted by low/mid level frontogenesis and a
weak stability profile...arrives Sunday evening. Looks like a
quick hitting event (on the order of 6-9 hours of snow) but
potentially very efficient from a QPF standpoint given the
environment. The only downside for snow accumulation efficiency
is that SLRs may be dominated by a deep layer of temperatures
warmer than -10C (growth by accretion/riming/ aggregation which
lowers SLR). Precipitation may taper off to freezing drizzle as
mid level moisture strips out overnight as a deep saturated
layer remains behind for continued isentropic ascent to work on
(which likely continues into Monday). Current snowfall
expectations are for 4-6+ inches north of a Leland to Gladwin
line...and 2-4 inches south (mainly the southwest corner of the
forecast area). Don`t believe that blowing/drifting snow will be
a huge impact.

Midweek precipitation chances??:  Looking at a somewhat similar
system moving in later Tuesday/Tuesday night...though warmer aloft
but with marginal surface temperatures so there is an array of
potential precipitation types with this system.

Potentially milder end of week but also more unsettled with
rain/mixed precipitation:  Southerly boundary layer flow and higher
heights aloft pointing toward an early January warm-up for Thursday-
Friday...with highs in the 30s and perhaps getting near 40.  But as
is typical with the warm air will come increasing precipitation
chances with indications of a surge of moisture getting pulled
northward.  Plenty of questions as to what this system will look
like which will also likely have impacts on precipitation types so
stay tuned.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1208 PM EST Sat Jan 3 2026

-SN/-SHSN will continue to move across terminals this afternoon
 and evening, with VSBYs 2-4SM, occasionally lower, down to 1SM
 perhaps. Winds remain west to northwest through the period,
 generally 5 to 10 KTs. -SN diminishes through the evening at
 terminals, and especially overnight. CIGs largely MVFR through
 the period, OVC015-025, perhaps briefly lifting to VFR at
 times this afternoon and into the overnight at KAPN.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...Winter Weather Advisory until 5 AM EST Sunday for MIZ086-087.
MARINE...Small Craft Advisory until 5 AM EST Sunday for LSZ321.

&&

$$

DISCUSSION...JPB
AVIATION...JLD