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Area forecast discussion 
National Weather Service Gaylord Michigan
820 am EST Tuesday Dec 1 2015

issued at 756 am EST Tuesday Dec 1 2015

A quick update since the latest sounding...fairly dry air mass
from about 910mb up to 710 mb with the temperatures in the air
mass well above freezing. This looks to be creating some melting
with the rain falling into the dry air. However, the wet bulb
temperatures are below freezing all the way to the surface. This has
helped to produce sleet mixed in with the light rain, which has
helped to produce slippery roads over the early morning.

This should come to an end as the surface temperature warm, along with
the moisture moving into the region that is lowering the clouds
heights across northern Michigan. The moisture will put the
dewpoints aloft, and thus the wet bulb temperatures above freezing
allowing for all rain to fall.


Near term...(today through tonight)
issued at 356 am EST Tuesday Dec 1 2015

Occluded/stacked low now situated over eastern North Dakota/SW
Minnesota this morning...surface front arcs S/east across Illinois.
Trowal feature ahead of the surface front and axis of strong qg-
ascent now rotating up into northern Michigan with another band of more
widespread precipitation just nudging into northwest lower Michigan. Radar
bright banding and dual-pol products suggest this next batch of
precipitation is still a bit mixy...despite a well established warm nose

Today...trowal and axis of strong qg-ascent will swing up through
the region this morning into the afternoon bringing another period
of categorical precipitation to the County Warning Area. Precipitation type and timing is the
biggest forecast issues. Have kept precipitation mixy through early this
morning and will just have to see how things evolve. Surface temperatures
everywhere are above freezing but just barely in some locations.
So...still possible we see some minor icing as this next batch of
precipitation swings into the region and will issue another Special Weather Statement to talk
about minor icing for the morning commute. This afternoon...pronounced
dry slot will follow the occluded front S-north and bring an end to
the precipitation (perhaps ending with a period of drizzle).

Tonight...upper low/core of colder air and deeper moisture edges
into the region...which should start to spread another batch of
synoptic precipitation (back to snow) into the western part of the County Warning Area.
SW flow lake enhancement will eventually come into play as 800 mb
temperatures cool to -6c or colder and may bring some light accumulations
to areas near Lake Michigan.


Short term...(wednesday through Thursday night)
issued at 356 am EST Tuesday Dec 1 2015

High impact weather potential: minimal

Pattern synopsis/anticipated evolution: much talked about upper
level low now making its way east across the Central Plains. Larger
scale shows split flow regime of recent weeks continuing...with said
upper low helped along by strong subtropical jet punching into the
Southern Plains...while northern stream flow is well removed to our
north across central Canada. Upper low will continue to track
east...crossing our area through midweek. Pattern remains anything
but December-like heading into the end of the week...with northern
stream remaining off to our north...bottling anything up that
resembles winter well up in Canada.

Primary forecast concerns/challenges: addressing lingering rain/snow
issues Wednesday. Temperature and cloud trends through the forecast.

Details: gonna actually feel just a bit like December Wednesday as
upper level low crosses overhead. System linked cold pool and pocket
of deeper moisture does the same...both working in tandem to drum up
at least some lake response. Wind fields remain weak and
disorganized...especially with hints of weak surface low (partially
lake induced itself?) Passing across lower Michigan. Will continue
to confine better precipitation chances to northern lower...with best
potential in favored west to southwest flow areas (a good a starting
point as any). Surface temperatures will remain marginal at best for
any snow accumulation...and still believe we will be dealing with
precipitation type issues (rain/snow) by the afternoon. All in
all...really cannot envision much more than an inch...even under the
most persistent snow shower activity.

System departs to the east Wednesday evening...with Post system dry
advection and rising heights putting an end to any lingering showers
by Thursday morning. High pressure and warm air advection rule on Thursday...
bringing dry conditions and highs averaging at least a few degrees
above normal. A touch more uncomfortable about cloud trends...with
strong and increasing hints in guidance that low level moisture will
be trapped under strengthening subsidence inversion. Will trend
cloud coverage up considerably...but still not go as aggressive as
most guidance would suggest. Weak and moisture starved northern
stream wave attempts to drag a "cold" front/surface trough into
eastern upper Thursday night. Guidance consensus blend has a very
low threat for a few rain/snow showers with this feature north of
the big bridge.


Long term...(friday through monday)
issued at 356 am EST Tuesday Dec 1 2015

Long term (friday through monday)...unbelievably uneventful about
sums it up. Transient ridge/moisture starved trough/ridge
configuration through this period. Cold air nowhere to be
found...with 800 mb temperatures averaging several degrees above zero.
Surface temperatures respond accordingly...with highs through the


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 647 am EST Tuesday Dec 1 2015

MVFR ceilings anticipated through the upcoming forecast period. Occluded
front and corridor of rainfall will slide up through northern lower
Michigan through midday today. Precipitation ends S-north this afternoon with
some improvement in ceilings...but still remaining MVFR. Colder air
and some snow showers wrap back into the region tonight.

Winds...stronger winds aloft will result low level wind shear at the terminal
sites through this morning. Winds veer southwest after passage of
the front and a bit gusty with colder air then rotating back into
the region.


issued at 356 am EST Tuesday Dec 1 2015

Gustier southeast winds this morning will veer southwest this afternoon
as low pressure moves up through the western Great Lakes. Small
Craft Advisory winds/waves anticipated through today and this
evening as this system moves through. Winds/waves diminish tonight
and remain under headline criteria through midweek.


Apx watches/warnings/advisories...
LH...Small Craft Advisory until 1 am EST Wednesday for lhz345>349.

Lm...Small Craft Advisory until 1 am EST Wednesday for lmz323-341-342-

Ls...Small Craft Advisory until 7 PM EST this evening for lsz321-322.



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

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