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fxus63 kapx 152116 
afdapx

Area forecast discussion...updated
National Weather Service Gaylord Michigan
351 PM EST Fri Nov 15 2019

Near term...(through tonight)
issued at 345 PM EST Fri Nov 15 2019

Updated wwa section

..light snow showers diminishing and very cold tonight...

High impact weather potential...minimal

Synopsis/forecast: afternoon analysis continues to show troughiness
over Hudson Bay, with a subtle wave rotating around its base into
Lake Superior. The surface reflection of this has pushed into
western Quebec with the cold front progressing south through
Michigan. Cold air advection and gusty winds has followed in its wake. This may
eventually allow some very light lake effect flurries to make their
way into northern lower, but confidence in this occurring before
Sundown is currently low. Subsidence and dry midlevels has helped
keep any flurries at Bay thus far. However, light snow showers have
been persistent over portions of ern upper (such as the Soo and
kinross) through the day, thanks to deltat's over Lake Superior
reaching 15 to 20 c and fairly unidirectional northwest winds through the
boundary layer. An area of gusty winds behind behind the front are
pushing south, with gusts into the upper teens possible through the
early evening hours. High pressure currently treking south through
Manitoba moves over The Straits overnight, leading to lighter winds
overnight into Saturday morning. Continued drying under this high
pressure should allow skies to mostly clear out for the majority of
the area, thus kept close to inherited low temperatures. Increased
overnight lows by a couple degrees given uncertainty and short
possibly timeframe of clearing. As winds veer around to easterly
then southeasterly late tonight, some low clouds may start to push
inland from Lake Huron.

&&

Short term...(saturday through monday)
issued at 345 PM EST Fri Nov 15 2019

..Lakeshore flooding? maybe? otherwise a break and minor snow...

High impact weather potential...winds out of the south could present
some minor flooding issues in Upper Michigan, Saturday night.

Pattern synopsis/forecast...Saturday morning the 500 mb ridge is
passing through the region. However, as it does, the sfc winds turn
southeast and with the Lake Huron SST around 9c and the -6c 850 mb
temperatures are well down the Lake, Lake effect into portions of NE
lower and east upper are possible, but the amounts would be minor to
light (probably minor) as the air is dry. In east upper the moisture is
a little better so light amounts are possible although some of the
winds could push it into Ontario. After 18z/Sat, the winds will be
more south, and are unlikely to produce any precipitation in east
upper, but all across the international border. High pressure then
settles in Saturday night. The next system, a clipper system, begins
to threaten precipitation Sunday morning in the western part of
Mackinac and Chippewa counties increasing along the warm front as the
sfc and 500 mb low approaches. The 500 mb trough cuts off, sfc low
moves and begins to fill and lift to the north. Precipitation
diminishes overnight and into Monday. Precipitation types look to be
a mix during the day, and mainly snow overnight. There are some
early indications of drizzle or freezing drizzle possible Monday
morning.

Primary forecast concerns...there are a couple of concerns. As
mentioned earlier, the winds out of the S could produce some
flooding issues, along the South Shore of east upper, but at this time
with only small craft winds and waves, it doesn't look like it would
rise to an advisory. However, it is something to keep an eye on.

The next issue would be onset of precipitation on Sunday (probably
snow) into the east upper as the SW winds move over North Lake Michigan
again. 850 mb temperatures are way too warm for lake enhancement to
start anything. However, the models today have backed the start time
off from Saturday night into Sunday late morning/afternoon. The GFS
and European model (ecmwf) bring things in after 18z/sun, but the sref is after
21z/sun. It would not be surprising to see that south wind flow is
out of a dry air mass could delay this a little more on the upcoming
model runs and delay it into Sunday night.

&&

Long term...(monday night through friday)
issued at 345 PM EST Fri Nov 15 2019

High impact weather potential...minimal

Monday night, things begin to dry out. However, Tuesday, the next
clipper moves into the region and brings mixed precipitation, or
maybe rain during the day. Looks like the precipitation breaks,
Tuesday night, again before a more southern, Pacific system moves
across the northern plains and into the upper Mississippi Valley
on Wednesday. Rain looks most likely before the cold front moves
into the forecast area on Thursday and brings snow Thursday
afternoon into Thursday night. Friday, with the northwest winds, and the
-10c 850 mb temperatures, will expect that lake effect will be
possible.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1252 PM EST Fri Nov 15 2019

Conditions will be primarily VFR through tonight into Saturday
morning. A few areas of MVFR ceilings will occur this afternoon
and early evening. A cold front has progressed through northern
Michigan today with gusty winds behind it. Gusts into the upper
teens will remain possible through Sundown, then high pressure
moves in with light winds overnight into Saturday morning. Winds
veer from northwest this afternoon, to northeast overnight, and
finally easterly or southeasterly Saturday morning.

&&

Marine...
issued at 345 PM EST Fri Nov 15 2019

Gusty winds are in place behind a cold front departing the
region; small craft advisories are in effect on Whitefish Bay and
Lake Huron through this evening. Winds will continue their
diminishing trend through the evening hours. Then as high pressure
moves into the region, winds go relatively light overnight.
Directions will be shifting throughout the evening and overnight, as
winds veer around to the northeast overnight and easterly or even
southeasterly Saturday morning.

&&

Apx watches/warnings/advisories...
Michigan...none.
LH...Small Craft Advisory until 10 PM EST this evening for lhz347>349.
Lm...none.
Ls...Small Craft Advisory until 7 PM EST this evening for lsz321.
&&

$$

Near term...stj

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