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Area forecast discussion 
National Weather Service Gaylord Michigan
647 PM EST Sat Dec 20 2014

Near term...(this evening through tonight)
issued at 413 PM EST Sat Dec 20 2014

High pressure sitting squarely overhead will inch off to our east
tonight. Meanwhile...low clouds trapped under the subsidence
inversion are expected to remain across western zones...despite
limited lifting of that cloud layer that has occurred so far today.
As the winds veer into the south southwest...these clouds are then
expected to begin to spread into eastern zones after midnight as
well. Otherwise...there will be a decent amount of middle cloud moving
up from the south (per latest satellite imagery). It is an extremely
tough temperature forecast once again as any clearing will likely
lead to a rapid fall (due to continued light winds). Forecast lows
ranging from the middle and upper 20s southwest to the single digits
above zero across far eastern zones will suffice for now (though
adjustments by the evening shift will almost certainly be
required).

&&

Short term...(sunday through tuesday)
issued at 413 PM EST Sat Dec 20 2014

..some light snow to finish off the weekend then turning wet...

Overview: another round of strong Pacific jet energy is plowing into
the West Coast today bringing heavy rain/snow to the Pacific northwest...a
piece of which will eventually bring the Great Lakes/Midwest active
weather during the upcoming Holiday week. Downstream...a bit of a
split flow configuration across noam with the strongest branch of
the westerlies running through the southern states. A bit more
disorganized and "rippled" across the northern states with a couple
small scale short waves...one in the northern plains and a second short
wave trough axis moving through the Midwest/Ohio Valley. No
substantial weather with this feature...just an axis of middle-high
cloud cover sliding through the region and a little bit of light
snow up in The Arrowhead of Minnesota.

Sunday...short wave trough axis and thicker middle-high cloud cover
will push east of the region Sunday morning followed by subtle short
wave ridging sliding into the area through the afternoon. Should be
a dry day for the most part. But stratus issues will continue to
plague the region as SW flow strengthens and pulls upstream low
level moisture/clouds into northern Michigan in earnest. May be some
sunshine in parts of NE lower Michigan to start the day...but I
think that will be fleeting.

Sunday night into Monday...will start to see the first glimpse of
our midweek storm system my Monday morning as strong short wave
energy and deepening surface low pressure emerges out of British
Columbia and starts to dig into the northern plains. This should provide
a better idea of just how things will unfold for Midwest. But in the
interim...initial warm advection forcing downstream of the low
/resulting light snow develops across the upper Midwest and slips
across the northern Great Lakes...Sunday night into early Monday bringing
a batch of light snow to the northern reaches of this County Warning Area. Inherited
forecast still looks on track in this regard with only minor
cosmetic tweaks made to the forecast.

Monday through Tuesday...still a bit of forecast uncertainty over
just how things evolve through the first half of next week with
various model operational solutions and ensemble members giving
slightly different timing/placement of relevant features. But at
this point it does appear that this system will end up a rain maker
for much of the state through at least Tuesday. Short wave trough
closes off and deepens through the plains/Midwest...Monday night
into Tuesday...with attending surface low sliding into the western Great
Lakes. Deep warm air/moisture transport develops ahead of this
system Monday night. Aided by exit region upper jet forcing that
noses up into the lower Great Lakes by Tuesday...we should get a
nice slug of widespread rainfall (potentially mixed with snow across
eastern upper) heading into Tuesday morning with some possibilities
of dry slotting Tuesday afternoon. Again...no major changes to the
going forecast at this point.

&&

Long term...(tuesday night through saturday)
issued at 413 PM EST Sat Dec 20 2014

High impact weather potential: significant storm possible Wednesday-
Thursday and another possible snow maker Friday.

Newest model runs have moved the track of the low pressure system
even farther west...now running northward through Michigan with only
a 983mb center while overhead northern Michigan. European model (ecmwf) has pressure
dropping to 970mb over James Bay while the GFS is just east of James
Bay only dropping to 978mb. Still looks like all rain to begin with
and changing over to snow late Wednesday into Thursday. As mentioned
yesterday...the snow will begin as a very wet and heavy snow with
temperatures near freezing and surface temperatures won't even drop
below freezing until Thursday afternoon. So for the first several
hours of snow falling...it will be hard...if not impossible to get
it to accumulate on the ground. Again...one thing to keep in mind is
to keep an eye out for any of this heavy snow that does accumulate
on trees to have the wind cause power outages. 850mb temperatures
still look dismal for any lake effect or lake enhanced snows to
develop.

Models disagree tremendously for the second low pressure system that
develops and begins to effect the Great Lakes region Friday...with
the European model (ecmwf) tracking it through the Detroit area and the GFS through
eastern upper! Obviously the implications of the two tracks are
completely different. Will just carry chance probability of precipitation for now until
greater confidence is established. 850mb temperatures in both models
agree that they will finally be cold enough for lake effect snows
late Friday into Saturday morning...but the moisture needed departs
east behind the system. All in all...it/S just not looking like
favorable setups through the extended period for lake
effect/enhanced snows.

Temperatures will be in the upper 30s Wednesday...but only reach
near freezing to the middle 30s Thursday and around 30 Friday. Low
temperatures Wednesday morning will stay above freezing...only
dropping into the middle 30s...while Wednesday night temperatures will
drop from the middle to upper 30s down to freezing by Thursday morning
and continue to fall throughout the day...dropping into the upper
20s by the afternoon. Friday and Saturday morning will be in the low
20s.

&&

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 647 PM EST Sat Dec 20 2014

MVFR to VFR ceilings.

High pressure over eastern lower Michigan and Lake Huron will slowly
move east...allowing southerly flow to develop. Ceilings have bubbled
up to VFR this evening...but should tend to descend back to MVFR
late this evening or overnight. There has been some -dz/-fzdz well
downstate early this evening...some potential for this to drift
north toward mbl/tvc very late tonight or Sunday morning.

Calm winds tonight...light S to southeast surface winds Sunday.

&&

Apx watches/warnings/advisories...
Michigan...none.
LH...none.
Lm...none.
Ls...none.
&&

$$

Near term...Sullivan
short term...Adam
long term...tjl
aviation...jaz

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