National Weather Service - Area Forecast Discussion

000
FXUS63 KAPX 280843
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
343 AM EST Sat Jan 28 2023

.NEAR TERM...(Today through Tonight)
Issued at 339 AM EST Sat Jan 28 2023

...Lake Effect and System Snow...

High Impact Weather Potential...Low to Medium.

Primary Forecast Concerns...Snow accumulations through tonight.

Challenging forecast today into Sunday morning from the combination
of colder air activating the big lakes and a system passing by to
our south.

Despite very good over lake instability, ongoing lake effect snow
showers have weakened across northern lower due to diminishing
moisture. Expect continued light snow showers/flurries across west
northwest flow favored areas into the late morning hours but with
little to no accumulation. Meanwhile across eastern upper where
moisture remains more plentiful snow showers should continue for
most of the day. Another couple of inches of accumulation likely in
the normal snowbelts of Chippewa county, especially near Whitefish
and Paradise.

The flow becomes light this afternoon across northern lower putting
a damper on any lingering snow shower activity. Attention will then
turn to an area of low pressure in the central Plains. This system
will head northeast and is expected to pass across the far northern
Ohio Valley/far southeast lower Michigan Sunday morning. Models are
in generally good agreement that the associated moisture shield will
reach up into much of northern lower Michigan tonight into Sunday
morning. In addition, it`ll be plenty cold enough for enhancement of
off Lake Huron. As a result, expect a swath of 3 to 5 inches of
accumulation from Alpena southwest to near Saginaw Bay. Therefore
will have a winter weather advisory starting this evening going into
Sunday morning for those areas. Elsewhere across northern lower, 1
to locally up to 3 inches of accumulation is likely. Across eastern
upper, more lake effect off of Lake Superior with another inch or
two possible up that way tonight.

Colder today with highs ranging from the upper teens far north to
the mid and upper 20s southeast. Lows tonight ranging from the
single digits above zero north to the teens to near 20 south.

&&

.SHORT TERM...(Sunday through Monday)
Issued at 339 AM EST Sat Jan 28 2023

...Continued snow and cold...

High Impact Weather Potential: Minimal for now. Watching
accumulating lake effect potential.

Synopsis/Forecast: Broad scale troughing remains across much of the
CONUS...with a few shortwaves rotating around an upper level low
centered over Hudson Bay through the end of the weekend into early
next week. One wave will be departing with its associated surface
low moving through the lower Great Lakes early Sunday...bringing us
lingering synoptic snow transitioning to lake effect. Another moves
through southern Ontario early Monday, bringing more snow to the
region.

Forecast Details: We`ll spend Sunday sandwiched between the weak
surface low moving through the Ohio Valley into New England and a
strong high pressure sliding into the northern Great Plains. This
leaves our winds mostly northerly through the first portion of the
day, backing to northwesterly as the high creeps closer. The only
caveat would be lake aggregate troughing keeping winds more variable
north of the bridge, until NW flow tries to take over.

Synoptic moisture moves off to the ENE through the day, decreasing
system snow intensity/coverage in the southeast. Elsewhere in
Northern Lower we`ll have snow showers linger through the
morning...with minimal additional accumulation through the day.
There`s a chance many areas of northern lower (outside of typical
WNW flow lake effect belts) may be dry through much of the day after
synoptic snow moves out in the morning. Guidance wants to dry things
out above the ~4 kft inversion, which may help limit accumulations.
A brief swath of dry air may impede snow production early Sunday
night, but any dry time is short-lived as moisture increases ahead
of the next wave moving by the region later in the night. Sunday
night also brings abnormally cold (-1 to 2 St. Dev) 850mb
temperatures which lasts through Monday at the very least. This will
obviously enhance overlake instability heading into Monday, but
we`ll once again struggle with decent synoptic saturation. The
system moving by to our north may aid snow chances north of the
bridge on Monday as well.

Overall the short-term will be cold (with highs around 5 to 10
degrees below normal) and snowy, with lake effect lasting off and on
in the typical W and NW flow belts, with minor accumulations in many
areas. There`s is definitely potential for some heavier
accumulations through early week, but this will depend on exact
direction and thermal/moisture profiles over the lakes.

&&

.LONG TERM...(Monday night through Friday)
Issued at 339 AM EST Sat Jan 28 2023

...More snow and cold...

High Impact Weather Potential: Minimal for now.

As we head through mid-week the core of the cold remains to our
north, and heights start to ever so slightly rise. This does little
to impact temperatures though, as afternoon highs look to remain in
the teens for most areas. A couple of systems passing by to our
north (a clipper late Tuesday, and potentially a weaker one
Thursday) will drum up additional snow chances on top of the off-and-
on lake effect regime. Overall a cold and slightly snowy week, with
no big synoptic systems in sight for the northern Great Lakes.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1051 PM EST Fri Jan 27 2023

A mix of MVFR and VFR cigs. -SHSN at CIU. -SN arrives at TVC/MBL
late Saturday.

Colder air will continue to spill into northern MI, with lake
effect clouds and snow showers. In northern lower MI, the best
lake effect snow will be between TVC and PLN. CIU will see
occasional -SHSN, with brief vsby restrictions. Late Saturday,
snow expands back into lower MI. MBL/TVC will see IFR conditions
develop Sat evening.

Gusty west winds will weaken tonight and Sat morning. Winds become
east by Sat evening.


&&

.MARINE...
Issued at 339 AM EST Sat Jan 28 2023

Winds will continue to diminish through this morning. Still a few
gale force gusts possible early this morning on Whitefish Bay and
along the Lake Huron shoreline. Winds then shift into the
northeast tonight with small craft advisories likely needed on
parts of Lake Huron. Expect periodic gusty winds Sunday into early
next week as a trough sets up residence across the Great Lakes.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...Winter Weather Advisory from 7 PM this evening to 10 AM EST
     Sunday for MIZ024-030-035-036-041-042.
LH...Small Craft Advisory until 10 AM EST this morning for LHZ345.
     Gale Warning until 7 AM EST this morning for LHZ346>349.
LM...Small Craft Advisory until 10 AM EST this morning for LMZ323-341-
     342-344>346.
LS...Small Craft Advisory until 10 AM EST this morning for LSZ322.
     Gale Warning until 4 AM EST early this morning for LSZ321.
     Small Craft Advisory until 10 AM EST this morning for LSZ321.
&&

$$

NEAR TERM...AJS
SHORT TERM...STJ
LONG TERM...STJ
AVIATION...JZ
MARINE...AJS

NWS APX Office Area Forecast Discussion