Area Forecast Discussion
Issued by NWS Gaylord, MI

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FXUS63 KAPX 211716

Area Forecast Discussion
National Weather Service Gaylord MI
116 PM EDT Fri Oct 21 2016

Issued at 913 AM EDT Fri Oct 21 2016

Radar looks as one would expect it should this time of year, with
north flow lake effect impacting the Lake Michigan and Lake Huron
shorelines. Local 12z raob actually shows pretty respectable lake
parameters, with H8 centered inversion level temperatures near -5c
and decent synoptic moisture through the boundary layer. These
parameters actually remain pretty decent through the day, although
lower level moisture does begin to thin with time. Cloud bearing
winds change little, suggesting those areas currently receiving
showers will continue to do so, with just perhaps a slight westward
adjustment to activity off Lake Michigan. Otherwise, interior clouds
will attempt to thin some during the remainder of the day, but still
expect more clouds than sun. North winds and those clouds will help
keep afternoon highs in the upper 40s and lower 50s (just a touch
below normal).


.SHORT TERM...(Today and tonight)
Issued at 336 AM EDT Fri Oct 21 2016

High impact weather potential: none.

Large surface high pressure stretches from far nw Ontario to the
southern plains. Low pressure in central PA is producing colder
cloud tops and rain to our east and se, but this is moving away from
northern MI. In between these features, cool northerly low-level
flow continues. The lakes are contributing cloud cover. A few
showers might be lingering in far western Chip/Mack. Better shower
coverage is seen near and w of M-66 in nw lower MI, and just
recently near and n of APN. Precip and cloud trends are the main

Today...kicker northern stream shortwave trof will move over
northern MI this afternoon. This will help hold off the high to our
west today, keeping the low levels cool and somewhat moist. 1000-
850mb will remain northerly but somewhat wobbly, veer nne this
morning and backing to n and nnw during the afternoon.

In eastern upper, the veering winds early this morning should tend
to push any lake effect showers west of Chip/Mack counties as the
morning proceeds. That trend will reverse itself in the afternoon,
and backing low-level (and 850mb temps hovering near -4c) could
return some showers to western Chip/Mack by late afternoon.

In northern lower, wind trends should also tend to push precip
westward this morning. By mid/late morning, expect most activity
in nw lower MI to be west of M-37. And backing flow should also
bring an eastward shift in the afternoon, and by late afternoon
the risk of showers should return as far east as M-66. In ne
lower activity is benefiting from the present veering low-level
flow. That will aid it this morning, but as things back this
afternoon, the fetch gets cut-off and precip there will end.

Bufr soundings a show persistent moist layer at 3-4k ft today, which
is reflected in the considerable amount of cloud cover seen to our
north. There will be some breaks, especially in interior sections,
and especially in eastern upper (which will benefit from down
downsloping flow this morning/midday). Breaks will also increase as
we head toward early evening, as the pass the diurnal heating/mixing
max. Overall, will increase cloud cover somewhat today.

Max temps will be mainly with a few degrees of 50f.

Tonight...upstream surface high tries to cross northern Lake MI
during the night, but doesn`t quite actually do so. Thus we get
toward the backside of the 850mb thermal trof, but can`t kick it
east with any authority. But with 500mb heights rebounding as the
kicker trof moves east, the mid-levels will dry and inversion
heights will tumble toward 5k ft. Though the nnw-flow effective
fetch looks lengthy thru the night, it gets cut down substantially
as 850mb warm advection gets underway as close as central Superior.
Some lake effect rain showers will be possible in the evening, west
of TVC/CAD. Little if anything in the way of precip expected after
midnight. Considerable cloud cover will remain west of I-75 in both
peninsulas, as well as from Rogers City to Harrisville. Elsewhere,
partly cloudy to mostly clear conditions.

Min temps will be near 30f to the lower 30s in most areas, but mid
30s to near 40f.

.LONG TERM...(Saturday through Thursday)
Issued at 336 AM EDT Fri Oct 21 2016

High impact weather potential: None.

Pattern synopsis/Expected evolution: Mid-upper level roughing across
the Great Lakes/Midwest is evident via tonight`s water vapor
imagery, aided by disorganized low pressure moving up the eastern
seaboard. As a result, cooler air continues to make its arrival
across the nation`s midsection through the weekend prior upper-level
ridging briefly prevailing toward the start of next week. A wave
exits the Intermountain West by midweek with cyclogenesis ongoing,
perhaps impacting portions of northern Michigan by late Wed -

Saturday - Saturday night:  Little in the way of consequence in
terms of sensible weather through the timeframe with weak warm air
advection ongoing, aiding to increase temperatures aloft and bring
and end to any lingering light effect rain showers. While it may be
warm enough to shut off any lake driven precip, cloud trends will
continue to be the main forecast challenge. Still plenty of cool for
lake induced strato-cu through at least Saturday morning, if not
sticking around through a portion of the early afternoon, especially
in NW flow lake effect prone locations. Slightly cooler than normal
temperatures are expected with highs ranging from the upper 40s to
low 50s.

Sunday - Sunday night: A rather weak, low amplitude wave is progged
to slide through the northern Great Lakes during the second half of
Sunday. While moisture and overall forcing remains paltry, will
continue inherited slight chance/chance PoPs across the northern two-
thirds of the area through at least Sunday evening. A brief warm up
is on tap for Sunday with temps ranging through the 50s...perhaps
into the low 60s across the far southeast.

Extended (Monday through Thursday)...

The main weather-maker for the extended period looks to revolve
around an area of developing low pressure progged to move from the
Rockies eastward toward the mid-Mississippi Valley, bringing another
threat for precip to northern MI during the Wed. night - Thurs. time
frame. Otherwise, near normal temperatures are anticipated
throughout with highs mainly varying from the low-mid 50s.


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 114 PM EDT Fri Oct 21 2016

Mainly VFR lake driven stcu expected at the taf sites into
tonight, with perhaps brief periods of MVFR cigs. Same story
heading into Saturday, with some breaks at times expected in the
overcast by later tonight into Saturday morning. Mostly light
north to northwest winds will continue.


Issued at 336 AM EDT Fri Oct 21 2016

Somewhat blustery northerly flow continues thru today, diminishes
somewhat tonight, then weakens more rapidly Saturday/Sat night as
high pressure to our west finally moves to our south. Small craft
advisories already in effect on Lake Huron south of Presque Isle
Lt, will evaluate the need for any additional advisories over the
next hour.


LH...SMALL CRAFT ADVISORY until 5 PM EDT this afternoon for LHZ348-



LONG TERM...Gillen
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