000
FXUS63 KAPX 181014
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
614 AM EDT Fri Aug 18 2017

.NEAR TERM...(Today through Tonight)
Issued at 325 AM EDT Fri Aug 18 2017

High impact weather potential: None.

Pattern synopsis and forecast:

Early this morning, a well defined negatively tilted shortwave
trough and associated sfc low pressure was over eastern Lake
Superior. Widespread low level convergence was over the region,
especially eastern upper, and the arrival of deeper low level
moisture has resulted in scattered to numerous light rains within
widespread low stratus. The pressure gradient was also tightening
across portions of NW lower Michigan in CAA, resulting in some gusty
westerly winds for coastal and exposed areas. Temperatures were
slowly coming down through the 60s under the thick low clouds.

The low pressure will slowly track eastward into western Quebec by
Saturday morning. The tighter pressure gradient will gradually swing
in over all of nrn Michigan through the day, resulting in gusty
westerly winds. Meanwhile, the veil of low clouds will overwhelm
most of the day and into the night for eastern upper and a good
chunk of NE lower. The scattered light rains will continue for much
of the day as sfc troughs rotate around the region through at least
the morning. Certainly expecting a more prolonged period of
scattered light rains into the higher terrain of nrn lower due to
upslope, and across eastern upper within a bit better low level
convergence. Eventually, the deeper low level moisture departs from
west to east, resulting in the end of any light rain, and gradual
clearing/partial clearing. Fog is not really a concern, as low
level winds will still be a shade too high.

Highs today in the upper half of the 60s, and lower 70s for
downsloping areas of NE lower. Lows tonight mainly in the upper half
of the 50s.

&&

.SHORT TERM...(Saturday through Sunday)
Issued at 325 AM EDT Fri Aug 18 2017

High Impact Weather Potential: Minimal.

Pattern Forecast: Upper trough and weakish shortwave energy will
swing into the eastern Great Lakes on Saturday, while stronger wave
slides through the Ohio Valley.  High pressure and building mid
level heights for the second half of the weekend.

Primary forecast challenge:  Isolated diurnal shower chances
Saturday afternoon.

Plenty of H8-H5 moisture still hanging around northern parts of the
area early Saturday as upper trough and weakish shortwave slides
across the area.  These lower clouds should fairly quickly give way
to partly sunny skies.  Weak boundary layer flow will allow for the
development of afternoon lake breezes, which will likely be enough
when combined with residual low level moisture (PWATs of 1"+ along
Lake Huron coast) to pop a few afternoon showers over northeast
lower.  High temperatures 5-8 degrees warmer than Friday, with most
locations in the middle and upper 70s.

High pressure more firmly in control on Sunday, with partly-mostly
sunny skies and high temperatures 4-6 degrees warmer than Saturday -
yielding highs in the lower to mid 80s.

.LONG TERM...(Sunday night through Thursday)
Issued at 325 AM EDT Fri Aug 18 2017

An elongated frontal boundary will be draped from the upper midwest
into upper Michigan Sunday night into Monday as low pressure works
its way out of the central Plains.  This low pressure area will
eventually bring this boundary southward across the entire area on
Tuesday, resulting in the best chance of widespread precipitation.
Cooler and drier conditions return for midweek.  So showers and
storms possible across the northern 1/3 of the area (especially Tip
of the Mitt into eastern upper) later Sunday night into Monday, with
rain chances increasing across the entire area Monday night into
Tuesday as low pressure and a fairly strong late summer cold front
pushes through the area.  Above normal temperatures to start the
week will trend below normal for mid to late week.

&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 612 AM EDT Fri Aug 18 2017

Scattered light rains will continue to impact primarily PLN
through much of today and into this evening. PLN can also expect
some potential minor VSBY reductions at times over the next few
hours. As deep low pressure tracks eastward thru the Northern
Great Lakes region, westerly winds will increase and become gusty
through the day. Skies will be trying to partially clear from west
to east through tonight.

&&

.MARINE...
Issued at 325 AM EDT Fri Aug 18 2017

Low pressure over eastern Lake Superior will track into Quebec
Saturday, while a ridge of sfc high pressure gradually settles in
over nrn Michigan Saturday night into Sunday. The pressure gradient
tightens across the region through the day, resulting in advisory
level winds all areas. Winds taper off from SW to NE through the
night, with advisory speeds to end last across presque Isle Light
Saturday morning. Scattered light rain can be expected through the
day with maybe some isolated light rains into this evening.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT through this evening for MIZ016-019>021-
     025-031.
LH...SMALL CRAFT ADVISORY until 11 PM EDT this evening for LHZ345>349.
LM...SMALL CRAFT ADVISORY until 11 PM EDT this evening for LMZ323-341-
     342-344>346.
LS...SMALL CRAFT ADVISORY until 11 PM EDT this evening for LSZ321-322.
&&

$$

NEAR TERM...SMD
SHORT TERM...JK
LONG TERM...JK
AVIATION...SMD
MARINE...SMD