000
FXUS63 KAPX 220843
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
343 AM EST Wed Jan 22 2020

.NEAR TERM...(Today through Tonight)
Issued at 344 AM EST Wed Jan 22 2020

...Messy snow in eastern upper MI late morning into evening...

High Impact Weather Potential: Moderate. Accumulating wet snow in
eastern upper MI.

High pressure is moving east across the upper OH Valley. Strong warm
advection extends from the southern plains into the Great Lakes
region. Somewhat breezy sw winds (on the windier side near Lake MI)
is nicely holding temps up early this morning. Readings are in the
mid 20s to lower 30s, near to several degrees warmer than normal
highs for Jan 22. (And a quick climate note: normal highs at both
TVC and APN actually go /up/ a degree tomorrow. Winter, I hardly
knew ye.)

Warm and somewhat moist air will return northward, and will get the
chance to interact with a weak shortwave glancing by Superior late
today. A substantially tightening thermal gradient will aid in the
development of banded precip, which the large bulk of model
solutions take across central and eastern upper MI. There are some
relatively healthy QPF answers from some models, and overall this is
looking like a snowier, higher impact system than it appeared over
the last couple of days.

Seeing some of snow starting to gather back near the WI/MN border,
so it`s got a ways to go to get here. This will quickly develop
eastward with time, and snow should break out in western Chip/Mack
Cos by late morning/midday. Sw 850mb winds of 30-40kt will be
feeding into this developing band of snow, providing both forcing
for ascent and moisture. Training and banded precip elements will
result in QPF totals between and 0.25 and 0.50 in Mackinac and
western Chippewa Cos today. Surface temps will be mild, especially
near Lake MI, where they will hover at 32-33f. That will sharply
limit snow-liquid ratios to something like 9-1 or 10-1, which
limits accums. But that also means a wet, slushy snow, that will
stick to tree limbs and other objects. Thankfully, winds will be
diminishing over land as the day proceeds, as the pressure
gradient at the surface relaxes. That means less in the way of
blowing/drifting, and less chance to bring down tree limbs and
power lines.

With all the above, snow amounts from midday thru this evening are
now in the 3-4" range in western Mack and sw Chip Cos. Per collab
with MQT (thanks!), have issued winter wx advisories for western
Chip/Mack. The other zone that could be included is eastern Mack;
the far western portion of that zone is also in the 3-4" range.
But the bulk of that zone is less, including 1-2" at St Ignace.
Have opted to leave them out for now.

Precip should really struggle to get much south of the bridge today,
as the low level airmass is drier, and we are displaced from the
better forcing. Don`t have much more than chance pops for the tip of
northern lower MI. However, it is less certain that ice will be
introduced to the cloud layer there. So those chance pops in the
Straits and far northern lower MI will include drizzle as well as
snow. Given surface temps, this does look like mostly just drizzle,
but suppose some glazing is possible given pre-existing cold
surfaces.

For late tonight, the low pressure system and associated frontal
zone is not advancing quickly, even as a weak trailing cold front
sags into Superior. But a slow-moving shortwave trying to eject into
WI will bring some inklings of height falls aloft into western
sections. This will spread light precip back into western sections
of the forecast area toward morning. This looks like mostly snow,
though with perhaps some raindrops mixing in along the coastlines
thanks to a warmer BL. Potential for another 0.5-1.0" of snow in
western Chip/Mack late in the overnight, less than that elsewhere.

Max temps today in the low-mid 30s. Min temps tonight in the low 20s
to around 30f.

&&

.SHORT TERM...(Thursday through Friday)
Issued at 344 AM EST Wed Jan 22 2020

...Light snow spreading into northern lower...

High Impact Weather...None is expected.

Forecast Concerns...Pops and snow amounts.

The strung out trough will continue to move slowly across the region
through Thursday night with some light isentropic ascent and div-q
noted. This should spread moisture southeastward into northern lower
Thursday during the day. Model soundings indicate that moisture will
be deep enough to support light snow. Accumulations for Thursday and
Thursday night combined are expected to be between 1 and 2 inches.
Precipitation should then fizzle on Friday as energy focuses farther
south. Temperatures will be several degrees above normal...generally
in the lower and mid 30s during the day and in the 20s at night.

&&

.LONG TERM...(Friday night through Tuesday)
Issued at 344 AM EST Wed Jan 22 2020

...Monitoring a storm which is expected to move by to our south...

High Impact Weather...None is expected at this time.

Forecast Concerns...Pops, mainly during the first half of the
weekend.

A very slow moving system still looks like it will track by to our
south across the northern Ohio Valley this weekend. Moisture on the
northern periphery of this system looks like it will make a run at
the southern half of the forecast area and possibly even farther
north. Models are definitely trending farther north. This could lead
to mainly light snow Friday night into Saturday. Short wave ridging
should then dry out all areas going into Sunday. A weak and moisture
starved upper level trough then moves across the region early next
week but with little noticeable impact expected on our sensible
weather. Arctic air is still shown to remain well north of the
region across the far northern territories of Canada through the
period and likely all the way into early February. Therefore, mild
temperatures are expected to continue for a while yet which would
inhibit lake effect snow from occurring. Extended models are hinting
that we may even be dealing with some rain just beyond the scope of
this forecast later next week which is definitely not welcome news
for snow mobilers, skiers and the like. Hopefully this solution will
change.

&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1150 PM EST Tue Jan 21 2020

Lake induced MVFR producing strato-cu should mix out heading
through early this morning, leaving behind just some high level
overcast. Clouds will gradually lower today, but remain at VFR
levels outside of KPLN where MVFR overcast looks increasingly
likely during the afternoon. Gusty southwest winds will continue
through the duration. Despite these gusty winds, overspreading of
low level jet likely to bring a round of low level wind shear
early this morning, especially at KAPN.


&&

.MARINE...
Issued at 344 AM EST Wed Jan 22 2020

Gusty sw winds continue, around departing high pressure in the
upper OH Valley. Gale-force gusts have been observed at Beaver Isl
and Naubinway. Gale warning continues there, with small craft
advisories elsewhere. Those advisories have extended a few more
hours, but winds/waves will slacken somewhat this afternoon into
tonight.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...LAKESHORE FLOOD ADVISORY until 5 PM EST this afternoon for
     MIZ016-020-025-031-088-095-096-098.
     WINTER WEATHER ADVISORY from 11 AM this morning to 10 PM EST
     this evening for MIZ086-095.
LH...SMALL CRAFT ADVISORY until 9 PM EST this evening for LHZ345>349.
LM...SMALL CRAFT ADVISORY until 9 PM EST this evening for LMZ323.
     GALE WARNING until 4 PM EST this afternoon for LMZ341-342-
     344>346.
LS...NONE.
&&

$$

NEAR TERM...JZ
SHORT TERM...AS
LONG TERM...AS
AVIATION...MB
MARINE...JZ

NWS APX Office Area Forecast Discussion