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Area forecast discussion 
National Weather Service Gaylord Michigan
343 am EST Sat Nov 28 2015

Near term...(today through tonight)
issued at 342 am EST Sat Nov 28 2015

High impact weather potential: none.

Pattern overview: blocking/split flow pattern remains over the
eastern Pacific with cutoff low pressure anchored over the western
Continental U.S. And the northern stream shunted well into northwest Canada. Flow
recombines over the upper Midwest/Great Lakes region with a fairly
strong upper jet core overhead of lower Michigan and ongoing
precipitation from the Ohio Valley into the plains. To the north...northern
stream short wave is dropping down through Manitoba...attending
cold front stretches through central Ontario into Manitoba. This
front will be sagging down into northern Michigan late tonight into

But meanwhile...surface high pressure ridge axis stretches from the
central/northern plains across northern Michigan. Wedge of deep layer very
dry air also spans the upper Midwest and northern lakes region.
But...low level cold air/over-lake instability has been enough to
maintain a fair amount of lake clouds across parts of eastern
upper and northern lower Michigan through the night. Capped by strong
isothermal layer above 2k feet...lake clouds have remained to
shallow to produce any least none seen on radar or observation.

Today...surface ridge axis and deep layer dry air will continue to sag
down through lower Michigan as low level mean flow turns more
westerly in time. Shallow cold air remains which brings concern
over lingering lake cloud cover for parts of the County Warning Area. But warming
and very dry air aloft...ongoing subsidence and lowering inversion
heights through the day should eventually squash remaining lake
clouds. It/S just a matter of timing. Will start the day with some
cloud cover over parts of eastern upper and northwest lower Michigan. But
eventually have all areas becoming sunny for the afternoon.

Tonight...clear skies anticipated to start. Then...upstream cold
front in Ontario this morning looking to sag down into northern
Michigan overnight bringing a renewed push of cool air. Quite a
bit of low cloud cover noted behind the front in northern Ontario which
will make a run at our area overnight into Sunday...particularly
eastern Upper Michigan and into the tip of the mitt areas and will
have those areas turn cloudy overnight. Temperatures...colder across the
southern half of the County Warning Area where skies remain clear and dipping through
the teens.


Short term...(sunday through Monday night)
issued at 342 am EST Sat Nov 28 2015

High impact weather potential: possible brief period of freezing
rain Monday night?

Pattern synopsis/anticipated evolution: pseudo looking western Rex
block reaches maturity later today with southern stream upper level
low becoming increasingly tucked under southwest Canada/northwest
Continental U.S. Middle and upper level ridging. Above breaks down rather
aggressively heading into next week as subtropical jet strengthens
and punches into the Southern Plains...all-the-while additional
upper jet core makes a run toward the West Coast. Combination of
these will help drive southwest system eastward...bringing an end to
what will be a dry and seasonal stretch of weather by Monday night.

Primary forecast concerns/challenges: focus on temperature and cloud
trends through Monday. Attention directed to precipitation evolution
(type/timing/coverage) Monday night.

Details: middle level confluence axis sets up right across the northern
Great Lakes Sunday into early Monday...with broad and slow moving
surface high pressure a byproduct of such. Airmass through the
column is a dry one initially...although uptick in lower level
moisture fields accompanies secondary push of cooler air from the
northeast on Sunday. As a result...definitely could see an increase
in stratocu across eastern upper and northeast lower Michigan...the
latter augmented by weakish Lake Huron contribution. Moisture depths
look much to shallow to support any precipitation. Confidence in
cloud trends Sunday night into Monday especially low...with the
often too moist NAM-WRF keeping widespread stratus across eastern
upper and much of northeast lower Michigan. Even hints of this in
the latest GFS...although not nearly as aggressive. Will trend more
cloudy for now (often a pretty safe rule in the fall/winter
season)....refraining from going quite as aggressive as the NAM
would suggest. Either way...Bone dry profiles through the middle levels
during the period will keep dry conditions prevailing. Airmass
slowly modifies through this period...with highs by Monday pushing
into the lower 40s...several degrees above normal for this time of

Changes begin to take place Monday night as that southwest system
mentioned earlier makes its move through the Central Plains. Broad
subtropical jet entrance region dynamics helps drive low level jet
development and attendant moisture advection north into our area
through the overnight. Near surface dry environment will be stubborn
to yield initially as dry east surface winds remain steadfast.
Persistence of moisture advection and 800 mb jet should complete top-
down saturation from south to north...with a deep enough moist layer
to allow precipitation to eventually reach the surface (have tried
to show a touch of temporal evolution given this initial dry
environment). Deep warm nose aloft should ensure what falls reaches
the surface as all liquid. Still have concern for a period of
freezing rain during beginning stages of precipitation given window
for temperatures to drop before rain arrives...along with a short
period of evap cooling via lower level dry air entrainment. Focus
for such would be across the interior Highlands...and given now
multi-cycle guidance trends and pattern recognition supporting
such...will go ahead and begin to introduce this potential into the
forecast and throw a mention into our latest hazardous weather
products. Not expecting a lot of ice...but it sure won't take much
to makes things slippery. Veering flow and latent heat release
should allow temperatures to warm overnight...ending the freezing
rain threat rather quickly.


Long term...(tuesday through friday)
issued at 342 am EST Sat Nov 28 2015

Long term (tuesday through friday)...upper low cuts right overhead
through midweek...with attendant cold core allowing rain to switch
over to snow from southwest to northeast during the day
Tuesday...and all snow expected Tuesday night into Wednesday. Main
moisture advection is well removed to our east during this
transition process...with precipitation coverage driven by
increasing lake moisture contribution set on background diurnal
processes and remnant synoptic moisture shield. Not looking like a
lot of snow...although suppose a few inches will be possible in
favored southwest flow areas. Still some uncertainty on just how
fast this system departs...although overriding theme is for dry air
and warm air advection to win out Thursday and Friday...with dry conditions


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1200 am EST Sat Nov 28 2015

An axis of high pressure is settling in over northern Michigan...and
winds continue to weaken. Lake stratus has expanded over the
lakes...but there is still enough cloud bearing wind in northerly
flow regimes for clouds hanging tough at tvc and apn. As land
breezes develop...lake clouds will travel out over the lakes and
all airports expected to go VFR. As west-northwest winds mix tomorrow
morning...could see brief lake clouds/MVFR drift back into
primarily mbl. Air mass dries from aloft and sky clear expected by
afternoon all airports. Light winds.


issued at 342 am EST Sat Nov 28 2015

Winds/waves expected to remain below headline criteria through the


Apx watches/warnings/advisories...


Near term...Adam
short term...msb
long term...msb

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