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Area forecast discussion 
National Weather Service Gaylord Michigan
1045 am EST Sat Feb 6 2016

issued at 1044 am EST Sat Feb 6 2016

No major surprises this morning. Did bump up snow amounts a bit
over the tip of northern lake enhanced snow peaked in
the 8-10am window. But things are clearly on a downward trajectory
since warm advection arrives in northern lower
(diminishing Overlake instability)...and a departing shortwave
starts 500mb heights rising as well. 1000-850mb winds are veering
a bit more westerly...displacing lake effect snow southward. We
will be backing again to the west-southwest by the end of the day...but by
then instability will be very marginal. A general diminishing
trend in snowfall intensity and coverage in northwest/north central looks
just fine for this afternoon.

The bigger question is in eastern upper. Colder air is in place
on Superior...and this brief period of veering winds is bringing
an earlier dominant SW flow band closer to Whitefish pt. Montreal
River radar indicates at least -shsn already grazing the point.
Latest short-range guidance does not veer 1000-850mb winds past
west...thus keeping the core of the band just off of Whitefish pt
until winds start backing again later this afternoon. For now...
will maintain high probability of precipitation north of Paradise this afternoon...but
keep accums limited (less than 2 inches).


Near term...(today through tonight)
issued at 327 am EST Sat Feb 6 2016

..nuisance precipitation issues continue...

High impact weather potential: minimal.

Overview: large scale troughing remains across the eastern half of
the Continental U.S. With several short waves moving through the mean flow. One
wave is moving through the northern Great Lakes region producing some very
modest light snow to parts of the state. Stronger short wave is
digging into the Gulf Coast states that will ultimately emerge as
a decent coastal low along parts of the Atlantic coast. Another
strong wave is advancing through Pacific northwest that will eventually begin
to impact our weather late in the weekend.

At the surface...weak low pressure analyzed over southern Ontario with a
cold front arcing back into central Canada. Thermal profile across
the Great Lakes is just cold enough (-10c to -13c) to produce some
modest lake enhancement...and primarily across Lake Superior. But
overall snowfall thus far has been underwhelming.

Today...short wave trough will be crossing/exiting the region
this morning while attending surface low continues into Quebec and
front becomes stretched out across the u.P. So...we never get
into the colder air per southeast. But with another round of increased
moisture/clouds...persistent west-southwest flow off Lake Michigan and modest
heat moisture flux off the lake...suspect we will once again see
clouds and light snow showers/flurries fan out across a good
portion of northern lower Michigan this morning. However...we should
see a quicker diminishing trend through the afternoon hours as
warmer/drier air begins to spreads into the region and inversion
heights lower substantially. Just minor accumulations (under an
inch) across parts of northwest lower Michigan and tip of the mitt where
light snow showers will be the most persistent.

In eastern Upper Michigan...the northern part of Chippewa County might
do a little better if they can get some better defined lake
banding to dip into that area.

Tonight...Pacific short wave energy and attending deepening surface
low will move quickly into the northern plains/upper Midwest by Sunday
morning. Ahead of the low...short wave and warm advection
forcing expected to develop across upper Midwest and northern lakes
region...especially during the overnight hours. Little or no lake
enhancement with this system as low levels simply warm to much to
support it. But I do expect a batch of light snow to spread
across the u.P. And into the northern reaches of the County Warning Area by morning.
Have nudged probability of precipitation up into the likely category across eastern Upper
Michigan with light accumulations up near an inch.


Short term...(sunday through Monday night)
issued at 327 am EST Sat Feb 6 2016

High impact weather potential: nothing too significant. Some minor
snow accumulations at times.

Pattern synopsis/anticipated evolution: definitely no surprises
(always a good thing)...with well advertised pattern change to that
of a more amplified one in the coming days. Increasingly anti-
cyclonic curved strong and extended east Asian jet core kicking the
above into over-drive...helping drive rather rapid western noam
height rises. Leading edge of this jet core will dive into the
Central Plains...and when combined with digging shortwave
trough...will help carve out fairly deep Great Lakes centered
troughing by Monday and Tuesday. Northern Michigan will be dominated
by this latter feature...bringing a gradually return to colder
conditions...along with periods of mostly light snow.

Primary forecast concerns/challenges: temperature trends and light
snow evolution.

Details: not too bad of an end to the weekend...with primary focus
for light snow well to our west along digging wave...and to our
north in vicinity of northward surging warm front. Could see a touch
of snow/flurries...especially across eastern Upper Michigan. Sub 700 mb
layer remains rather dry for northern lower...suggesting any
meaningful snow (snow/rain mixture?) May have a hard time reaching
the surface. Area will be in the "warm" sector...with highs likely
to exceed freezing by at least a few degrees across northern lower
Michigan...and nearing that mark for areas north of the bridge.

Same trends really continue right through Sunday night/early despite approach of rather impressive middle level
wave...deepest moisture simply rotates entirely around our area.
Really might not see much of anything during this period...with the
best chance for snow (light it will be) focused across northeast
lower and eastern Upper Michigan.

Better chances for light snow arrive second half of Monday into
Monday night as "deeper" moisture rotates overhead as surface low
slowly pushes off to the east. Once again...lack of any appreciable
deep layer dynamics and moisture will keep snow amounts
light...likely not more than an inch through Monday evening. Far
bigger concern is the increasing potential for developing lake
enhancement later Monday night in north-northwest wind favored areas
as system backside cold air advection intensifies. Becoming increasingly concerned
for areas along and south of the Leelanau as 800 mb temperatures dip into the
negative middle teens over Lake Michigan (with also hints of Lake
Superior contribution). Early perusal of guidance derived soundings
show...while limited...inversion levels are pegged in heart of
dgz...with plentiful synoptic moisture above this layer. Could see a
good seeder-feeder set-up to enhance snowfall rates. Now...with all
that said...there is still uncertainty in exact wind direction as
well as overall thermal environment. At least gonna start bumping
snow accumulations up in the favored areas...and introduce this
potential (along with Tuesday activity...see long term section
below) into our hazardous weather products.


Long term...(tuesday through friday)
issued at 327 am EST Sat Feb 6 2016

Long term (tuesday through friday)...trends are definitely
supporting a continuation of a lake enhanced snow event for favored
north-northwest flow areas of northwest lower Michigan Tuesday into
Tuesday night....with some lingering lighter snows elsewhere. Same
set-up as later Monday night...with lake induced convective layer
pegged through the dgz...with plentiful synoptic moisture above
inversion level. Only thing really lacking is good lower level
convergence signature...but still believe several inches of snow is
a real possibility from the Grand Traverse area on southward.

While system support and deepest moisture move off to the east
Wednesday into Thursday...some of the coldest air this winter slides
overhead...continuing the lake snow threat. Loss of synoptic
contribution should curtail the intensity some...but widespread snow
showers are expected in those north-northwest flow regimes (along
with more accumulation).

Plenty of uncertainty heading into Thursday night and Friday...with
some evidence of additional energy dropping through overhead
northwest flow environment. Not sold on any particular
solution...with dprog/dts of all guidance showing considerably
variability during this period. Simple consensus blend approach will
suffice for now...which does feature some additional light snow
shower chances and maintenance of well below normal temperatures.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 641 am EST Sat Feb 6 2016

Surface trough is currently in the process of slipping across northern
lower Michigan this morning. Lake Michigan shoreline convergence
along the trough has fired up some modest lake enhancement along
the shoreline from Grand Traverse Bay into The Straits...and will
bring a period of MVFR to possible IFR conditions to pln and tvc
over the next few hours. After passage of the trough...MVFR
conditions will settle across northern lower Michigan through afternoon
hours with lighter snow showers.

Tonight...warmer and drier air will spread into the region and may
erode away the lower ceilings...with possible return to VFR

Winds...some SW gustiness today...diminishing tonight.


issued at 327 am EST Sat Feb 6 2016

Some gustier SW winds will be felt on the lakes today...ahead of
low pressure across Ontario. Thus Small Craft Advisory conditions
are a good bet for Lake Michigan as well as parts of Lake Huron.
Winds will diminish a bit for this evening but increase again
overnight into yet another system rolls into the northern
lakes. Ongoing small craft advisories will remain intact...and I
may stretch them out into Sunday.


Apx watches/warnings/advisories...
LH...Small Craft Advisory until 6 PM EST this evening for lhz346>349.

Lm...Small Craft Advisory until 6 PM EST Sunday for lmz323-341-342-



near term...Adam
short term...msb
long term...msb

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