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National Weather Service Gaylord Michigan
120 PM EDT Wed Oct 26 2016

issued at 1258 PM EDT Wed Oct 26 2016

The forecast for the rain advancing across northern Michigan looks
good. Had to work on the le rain out ahead of the rain off of Lake
Huron this morning. This looks to be expanding ahead of the main
rain, along a band of f-gen, in some of the drier air. This looks
to get absorbed into the rain sometime this afternoon. It looks
like once the temperatures begin to fall late in the
afternoon/early evening, then we should see some of the mixes in
precipitation with the rain and snow. Most of the snow mixes
should be contained inland, as the lower lands, near the Lakeshore
should remain warm enough for it to be all rain.

Update issued at 957 am EDT Wed Oct 26 2016

Temperatures continue to warm ahead of the rain, and based on the
obs and radar, the rain has been slow to move into the region.
Used a blend of the hrrr/rap13/nam12 for the pops out through the
next several hours. So have a slightly slower progression for the
rain this morning. As mentioned the temperatures are warming
nicely, so an freezing rain won't be an issue today as most of the
areas are almost above freezing, and the places where there is
rain or at least sprinkles the temperature is much above freezing.


Short term...(today and tonight)
issued at 354 am EDT Wed Oct 26 2016 weather through midweek with some snow possible...

High impact weather potential: minor snow accumulations expected

Overview: broad scale ridging is in place through the central
Continental U.S. Connecting to long wave troughiness anchored over far
eastern Canada into the North Atlantic. Low amplitude short wave
trough is crossing the Central Plains into the Midwest with a
developing area of surface low pressure over eastern Nebraska and
warm front stretching southeastward through Missouri. Nearly
closed off 800 mb and 700 mb circulations analyzed over Minnesota and the
Dakotas. Already an active weather system with a large axis of
strong deformation and warm advection forced precip (aided by
upper jet entrance forcing) stretching from Minnesota into the
lower lakes region and additional shower/thunderstorm clusters
across Iowa and into Kansas. Across northern Michigan, quiet
weather for the time being with thickening high cloud spreading
into the region from the upstream system.

Today: deepening short wave trough will advance into the western
Great Lakes through this afternoon while attending surface low
crosses into the Chicago area by evening. Upstream axis of
precipitation will gradually overspread northern lower Michigan
this morning and into the afternoon, and eventually into eastern
Upper Michigan into this evening, with likely to categorical pops
warranted for most areas. Precip should largely fall as rain
through the day although some higher terrain areas could see a
rain/snow mix at the onset this morning.

Thunderstorm possibilities: narrow axis of instability pokes up
into the Midwest this morning supporting cluster of thunderstorms now pushing
into southern Wisconsin. Instability axis will largely slide
through Southern Lower Michigan and areas south today although an
isolated thunderstorm or two is certainly possible the far
southern counties. But have not included any thunder mention in
the forecast at this juncture.

Tonight: mid level circulation center crosses northern Michigan
with the surface low tracking across the Detroit/Toledo area by
Thursday morning. Deformation precip axis will slide across
northern Michigan tonight before diminishing and exiting the
region on Thursday. But precip type becomes an issue as we get
into the nighttime cooling cycle and undergo additional dynamic
cooling aloft. Forecast soundings/top down analysis support a
rain/snow mix for many areas (away from the immediate lake coasts)
and perhaps a flat out complete changeover to snow across the
higher terrain of northern lower Michigan as well as eastern Upper Michigan.
Temps may remain just a hair on the warm side for any significant
accumulations, and the warm marine layer will certainly play a
role near the coasts. But I have up to half an inch in the higher
terrain of northern lower Michigan as well as eastern Upper Michigan.

Long term...(thursday through tuesday)
issued at 354 am EDT Wed Oct 26 2016

High impact weather potential: none.

Pattern synopsis/expected evolution: fairly amplified pattern across
the Continental U.S. Tonight with troughing centered over the East Coast,
ridging over the midsection of the nation with another well defined
trough off the West Coast. Lee side cyclogenesis is ongoing across
the Central Plains tonight with an associated well defined shortwave
evident on tonight's water vapor imagery. This feature will track
through the southern Great Lakes through Thursday before ridging
begins to build into the region locally, only to be dampened by
another northern stream wave diving out of Canada into the Great
Lakes late Friday into the upcoming weekend.

Thursday - Thursday night: low pressure continues to shift off to
the east throughout the day with showers lingering into the early
afternoon hours, especially east of I-75. Wouldn't be shocked to see
a few more snowflakes mixing in across the higher elevations during
the early morning, but should be shut off rather quickly thanks to a
late October sun angle/diurnal cycle and increasing warm air advection. While pop
grids will reflect synoptically driven precip diminishing, will
continue to include low end pops in northwest flow lake effect areas
Thursday afternoon despite exiting synoptic support/moisture with
lingering cool air overhead (h8 temps of roughly -3 c and Delta ts
of 17-18 c). A drying trend everywhere is expected Thursday night as
even any lingering light lake effect is expected to wind down as warm air advection
really ramps ahead of the next approaching system from the west.

Friday - Friday night: well-defined northern stream shortwave and
associated deepening area of low pressure become centered over
northern Minnesota by Friday afternoon. With strong low-mid level return
flow gradually increasing moisture, would expect at least scattered
isentropically driven precip to be move across portions of the area,
mainly north of M-32 and especially across eastern upper prior to
sunset Friday. Could be breezy at times as well with a strengthening
pressure gradient as the system approaches. Model soundings would
suggest fairly stable low levels, thus limiting any really high
gusts from mixing down (50-55 kts at 925 mb, so it surely isn't far
off the surface). Will focus the highest gusts along both lake
mi/ the 20-25 mph range, but Worth monitoring for
higher gust potential in the next couple of days. Beyond the
daylight hours, the envelope of guidance solutions begins to Widen
with the potential for additional shower development across the
remainder of northern lower during the overnight hours. Overall, not
expecting area-wide appreciable rainfall. Seasonably mild Friday
night lows are expected...some 10-15 degrees above normal (ranging
from the low 40s far north to the mid 40s-50 elsewhere).

Extended (saturday through tuesday)...

A fairly active pattern continues through the extended period as a
couple of systems increase precip chances locally for a chunk of the
weekend and another early next week. Confidence is low on the
details in terms of timing, track, and location of best precip
potential, but will continue to carry chance pops for portions of
the remainder of the forecast period to represent such a threat.


Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1258 PM EDT Wed Oct 26 2016

Rain is making some head way against the dry air out ahead of the
system that will spread rain across the taf sites today. However,
at this time, the rain is only affecting mbl as the dry air has
impeded the rain at tvc, although lower clouds are now being
reported, so it only a matter of time. Pln is the only taf site
that is expecting any mix in precipitation overnight as the
temperatures cool enough to support a mix. The low move east
overnight and dry air should be moving into the region Thursday
morning, gradually stopping the precipitation across the region
through the day.


issued at 354 am EDT Wed Oct 26 2016

Gusty southeast winds develop on the lakes today and persist through
tonight, as low pressure tracks through far Southern Lower
Michigan. A few gales gusts are possible, but winds are expected
to remain largely below gale criteria. Will maintain scas for all
nearshore areas.


Apx watches/warnings/advisories...
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.



short term...Adam
long term...gillen

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