Area Forecast Discussion
Issued by NWS Gaylord, MI

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FXUS63 KAPX 270202

Area Forecast Discussion
National Weather Service Gaylord MI
1002 PM EDT Wed Oct 26 2016

Issued at 1001 PM EDT Wed Oct 26 2016

Area of rain and snow (mostly snow at the higher
elevations) continues to rotate east across northern lower Michigan,
with deep layer dry wedge just starting to be overcome north of the
big bridge. Mid level wave responsible for such slowly pushing east
into northern Lake Michigan, and will continue to track across our
area through the overnight. Thus, rain and snow will continue, with
snow looking to remain the predominate precip type across the
interior highlands of northern lower for at least the next several
hours. Subtle warming may transition precip to more liquid with
time, but not before some additional minor accumulation are
realized, bringing grassy surface snowfall totals up to and over 2
inches in some locations (already had just over an inch here at the
office). Roads are mostly wet, although have become briefly slush
covered during more intense snowfall rates. Fortunately, these
higher snowfall rates look to become more transient as earlier more
focused Fgen signal has been lost. Will cover slushy road concerns
with special weather statements as warranted. Persistent dry east
flow will likely cause a very sharp northern gradient to rain/snow
mixture, with current trends starting to really suggest little if
any activity ever reaches north of M-28 in eastern upper Michigan.


.SHORT TERM...(Tonight through Thursday)
Issued at 320 PM EDT Wed Oct 26 2016

High Impact Weather: First light snow accumulations in the higher
terrain areas.

Overview...An area of low pressure at the sfc in the mid-Mississippi
Valley and a 500 mb shortwave trough in the Upper Great Lakes, is
producing a wide spread area of rain and mixed precipitation over N
Lower at the moment. The snow has been a more than a mix in some
area near CAD with the minor accumulations on the ground over and in
the trees. Radar shows dry air and lighter precipitation moving into
the region, and across southern Lake Michigan. Dry air has been
impeding the rain along and north of M-68 this afternoon and in E

(10/26)Tonight...As the rain moves into the region, the sfc
temperatures have been diving to the wetbulb temperatures around 32-
33F this has helps to cool the lower atmosphere and produce the
little bit better snow in some of the higher terrain areas. This
will continue into the evening with the rain beginning to mix and
even change over for a time in NC and NE Lower. Was concerned that
we wouldn`t see any snow along the lakeshores, but considering the
temperatures along a fair amount of the region, will put a mix in
along the lakes with the some small changeover tonight. As mentioned
in the overview, the lighter precipitation and even some small dry
areas in the radar are showing up, and means that this initial
"burst" of snow should slow down and the ease up, so that the
amounts that are expected are going to be minor, with light amounts
possible, but unlikely across the forecast area, south of the M-68,
and probably M-32. As the low advances east overnight, to be in SW
Ontario by 12z, precipitation is expected to be diminish.

(10/27)Thursday...Dry air in the 700-500 mb layer looks to push the
moisture out of the rain through the day, bringing an end to the
rain by the afternoon. There are some hints of Lake effect rain
first on the lake michigan side, which by the afternoon falls apart
as the 1000-850 mb wind streamline ridge moves into the region. It is
possible that the Lake huron side may see some Lake rain in the
afternoon as the north to NNW wind flow patterns support the chance
of rain on the shore through 00z.

.LONG TERM...(Thursday night through Wednesday)
Issued at 320 PM EDT Wed Oct 26 2016

High impact weather potential: None.

Pattern synopsis/Expected evolution: Fast moving west-east flow
across the CONUS through the weekend, resulting in periods of
unsettled weather.

A drying trend Thursday night as any lingering light northwest flow
lake effect ends with rising heights and the onset of warm air
advection ahead of the next upstream wave.

Well-defined northern stream shortwave and associated deepening area
of low pressure become centered over northern MN by Friday
afternoon.  Strong low-mid level return flow will bring increasing
moisture into the Great Lakes.  Given the strong WAA, would expect
at least some scattered isentropically driven precipitation across
portions of the area, mainly north of M-32 and especially over
eastern upper prior to Friday evening.

Tightening pressure gradient throughout this period with low level
flow (925mb) increasing toward 50+ kts by Friday evening.  Despite
relatively stable low levels, believe some of this wind will mix
down to the surface, resulting in breezy conditions. Wind gusts
generally 15 to 25 mph, with gusts over 35 mph possible closer to
the coasts or within areas of showers.   Moderately steep lapse
rates (7 degc/km) work into the region Friday night along a mid
level theta-e gradient.  Because of this, can`t rule out a rumble of
thunder as well.  Scattered to likely showers across the area Friday
night with fropa (best chances across the northern 1/2 of the area).

Model differences grow on Saturday, tied to the fast moving flow and
difference in the handling of additional upper level impulses.  Lots
of clouds on Saturday with a few showers possible.  It will be a bit
breezy but temperatures should be fairly mild - 50s.


Extended 0Z SUN OCT 30 TO 0Z THU NOV 3

Primary concern for the extended is with a system developing in the
lee of the Rockies, and possibly impacting the Great Lakes around
mid-week. The system itself looks to pass to our north, but we could
see some enhanced rain chances as a weak cold front crosses the
state. Temperatures expected to run above normal through the period.



.AVIATION...(For the 00Z TAFS through 00Z Friday)
Issued at 733 PM EDT Wed Oct 26 2016

Band of mixed rain/snow and low cigs continues to advance slowly
north. Steadiest Fgen driven band of precip should slowly wane the
next few hours, replaced by more sporadic pockets of "heavier"
precip. Low clouds, however, should continue, keeping the ifr/mvfr
conditions right into at least the start of Wednesday morning.
Slow improvement expected the second half of the day. East to
northeast winds, occassionally gusty, will also continue.


Issued at 320 PM EDT Wed Oct 26 2016

Tonight through Friday...with the sfc low passing south of the
forecast area tonight, will expect E flow small craft criteria over
all of the lakes into Thursday morning. As the sfc low moves east of
the state, the winds in Whitefish bay and on the Lake Michigan side
are expected to diminish by 12z so that the winds to below small
craft criteria. Lake Huron winds will hold onto the stronger winds
through the day, but should have diminished by 00z (Thursday
night). Winds Thursday night will start out variable less than 10
knots, but increase out of the south as the next system begins to
exert its influence on the Upper Great Lakes by 12z/Friday. Winds
will begin to ramp up through the day, and be gusting to small craft
criteria by 15z on the lake Michigan side, in Whitefish Bay by 18z
and Lake Huron side by 21z. There is even a chance for some low end
Gale gust in the afternoon on the Lake Michigan side as well.


LH...SMALL CRAFT ADVISORY until 8 AM EDT Thursday for LHZ345.

     SMALL CRAFT ADVISORY until 6 PM EDT Thursday for LHZ346>349.

LM...SMALL CRAFT ADVISORY until 8 AM EDT Thursday for LMZ323-341-342-

LS...SMALL CRAFT ADVISORY until 8 AM EDT Thursday for LSZ321-322.



LONG TERM...Mayhew/Keysor
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