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Area forecast discussion 
National Weather Service Gaylord Michigan
402 am EST sun Feb 14 2016

Near term...(today through tonight)
issued at 353 am EST sun Feb 14 2016

Impact weather: brutal cold this morning...light system snow late

Synoptic pattern and observations:

Early morning analysis showing sharp upper troughing over the East
Coast...with a positively sheared shortwave and associated surface low
punching through the Dakotas. Snow was flying around the surface low and
also ahead of a warm front through Iowa/IL...within stronger forcing
applied by DPVA...warm advection and upper divergence. Surface high
pressure was over northern Michigan...but analysis of 00z apx sounding
and VAD wind profile shows that there is still some 15-20kt flow
through the mixed layer which still extends up to 800mb. Thus...lake
effect snows/clouds persist in the northwest flow regimes...but it is very
light and winds are weakening and backing more westerly with
time. We do have some drainage flow out of Ontario which has
seemingly resulted in a convergence area and band of light snow
bisecting eastern upper. While we do have many locations showing
land breezes...all lake effect clouds and snows will not push out
over the lakes until an 800 mb ridge over the western lakes can slide
in over US (lighter winds through the mixed layer)...which occurs
closer to dawn. Temperatures in clear areas were already as cold
as -15f...while cloudy areas were 10-15 degrees. Quite the range!

Synoptic pattern and weather evolution:

Land breezes will be in full effect by daybreak...and as winds
through the mixed layer weaken further...lake effect clouds/snows
will probably be out over the lakes then as well. Thus...the day
is expected to start clear and brutally temperatures will
likely be below zero everywhere...ranging from negative single
digits to well into the 20s below zero. Just a breath of wind will
result in a much colder feel...and advisories will be almost
everywhere for brutal wind chills. Bone dry air mass will keep skies
sunny for most through the day...but as winds swing around out of
the south and mix to the surface...some Middle Lake light snows/clouds will
push into western Mackinac County...and perhaps western Chippewa
County and Drummond Island. The upstream weak shortwave arrives
tonight with low to middle level warm air advection spreading from SW to NE across northern
Michigan. There is some disagreement on where the better forcing
targets...but we are likely to lose the upper divergence...leaving
US in a more weakly forced environment. does appear
that cloudy skies and at least a period of light snows develop from
SW to NE through the night. This will enhance/reinvigorate the lake
effect which will be coming in off lakes Michigan and Huron out of
the south. Using a parcel out over the water...inversion heights
will be shallow...under 3kft. This will result in some better
snowfall for far eastern and far western areas of Chippewa and
Mackinac counties in Upper Michigan. Will have to keep an eye on
maybe some of the "better" snows impacting/scraping coastal areas
of northwest/NE lower if the flow is not exactly due south.

As far as snow amounts...very minimal. A half inch or less
everywhere except far western Mackinac County...where a couple of
inches will be possible.

Highs today mainly 15-20f. Lows tonight mainly 5 to 15f...some
colder spots definitely possible across NE lower...away from
moderating influence of Lake Huron and where clouds arrive last.
There could be a quick drop off in the evening to colder readings.


Short term...(monday through Tuesday night)
issued at 353 am EST sun Feb 14 2016

..snow chances to continue through midweek...

High impact weather potential: minimal outside of varying snow
chances through midweek.

Pattern synopsis/forecast: large scale pattern has flattened out
across the eastern Pacific/western North America as a 180kt jet axis
extends from west of the dateline to the West Coast. Deep trough
remains over the eastern third of North America...with a couple of
quick moving low amplitude short wave troughs upstream over the
northern highs plains/along the Pacific northwest coast.

High Plains short wave trough will combine with high latitude energy
digging into the Canadian prairies to re-align the eastern trough
into central North America for the early part of this week. This
troughing will translate east through midweek...with rising heights
beyond Wednesday with short wave ridging building across the
plains/Midwest and eventually into the Great Lakes/Ohio Valley
around Thursday. Pacific-origin short wave trough expected to
impact the region later Friday/Saturday time frame. Arctic high
pressure over the Great Lakes early this morning will shift off the
East Coast by Monday morning with warm advection around the back
side of this high into Michigan. Weak surface reflection associated
with short wave energy slides across Michigan Monday...with a second
wave following quickly on its heels Monday night. Cold front
passage from the north looks likely by Wednesday.

Primary forecast concerns: the broken record of continued snow
chances (e.G., Gaylord Colorado-op station has recorded a trace of
precipitation every day since 8 january) with varying pieces of
energy passing through the upper lakes.

Monday...700mb short wave trough axis expected to be just upstream
of the forecast area at daybreak Monday...with snow expected across
the area out ahead of this feature. Synoptic component to snowfall
should wane as the day progresses as middle level trough swings through.
But another component to the snowfall will likely be along surface
trough axis which will lag the middle level feature...convergence along
this feature over Lake Michigan likely to result in a narrow north-
south snow band that will get advected east into Mackinac County and
northwest lower during the afternoon hours (could be a locally
intense snow band for an ~2 hour window). Some snowfall enhancement
also possible into far eastern upper/Drummond Island region in short
fetch southerly flow off Lake Huron. Given the two-prognosticated snowfall
threat plan to use a generic categorical pop through the entire day
for periods of snow should cover thing nicely. Snowfall
amounts from synoptic portion of the event expected to be light (~1
inch)...but will add a couple more inches across eastern upper/
northwest lower shoreline counties due to potential lake enhanced
component. But low level warm advection will gradually eat away at
lake induced instability Monday evening...and weakening boundary
layer flow will allow for land breeze components to eventually keep
more cloud cover closer to shore. A bit of a signal in model mass
fields for some fog potential across areas where clouds can thin
(e.G., Northeast lower)...though a weak secondary short wave trough
could bring some middle clouds to the area overnight. Also some
probability that lake precipitation may taper to a period of
freezing drizzle. mean long wave trough becomes re-established over the
Midwest... another short wave trough dropping in from central Canada
will push a cold front into the upper lakes by Tuesday evening.
Another round of widespread light snow expected to spread into
northern Michigan later Tuesday afternoon into Tuesday night.
Depending on timing of cold front could see a transition to
northwest flow lake convection by Wednesday morning.


Long term...(wednesday through saturday)
issued at 353 am EST sun Feb 14 2016

Renewed cold air push into Michigan on Wednesday as cold high
pressure builds across the Great Lakes Thursday. Temperatures
then moderate Friday as short wave ridging and brisk southerly
winds develop ahead of low pressure rolling through the upper
Midwest/Great Lakes region to end the week.

Wednesday through Saturday...colder Wednesday with some lake induced
snow showers though doesn't look to be a heavy snow setup.
Strengthening warm advection Thursday will likely push some
precipitation into northern Michigan...especially by Thursday night.
Continued guidance trends of push an elevated warm nose into the
upper lakes with surface temperatures potentially still near or a
little below freezing. So a wintry mix (snow/rain/freezing rain/
sleet) potential still in the offing Thursday night into Friday...
though may eventually become all rain during the day Friday with
potential for temperatures to warm well into the 30s/lower 40s. Will
start next Saturday out with a dry forecast.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1145 PM EST Sat Feb 13 2016

North/northwest flow lake effect snow showers will continue to impact mainly
northwest lower Michigan and the shoreline areas of far NE lower Michigan
around Rogers City tonight. Snow showers will diminish and push
offshore very late tonight into early morning in response to land
breeze development as the Arctic high moves overhead. Low level
winds will shift to the south Sunday on the backside of the
surface high center...with only scattered fair weather clouds
expected throughout the day. Low clouds will again increase Sunday
night...mainly for tvc and mbl...with chances of snow again
increasing from SW to NE later Sunday night in advance of a warm
front lifting into the Great Lakes region.


issued at 353 am EST sun Feb 14 2016

Arctic air will moderate some heading into tonight as light lake
effect gets a boost in spots due to light snow arriving from a
clipper system. Light and variable winds today will turn out of the
south/southeast and increase ahead of the clipper...likely reaching
advisory criteria tonight into Monday morning. A warm front blows
through late Monday with winds shifting more out of the south/SW.
The gradient is loose however...with winds under advisory levels
through Tuesday.


Apx watches/warnings/advisories...
Michigan...Wind Chill Advisory until 10 am EST this morning for miz008-



Near term...Dickson
short term...jpb
long term...jpb

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