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Area forecast discussion 
National Weather Service Marquette Michigan
1218 PM EST Tuesday Dec 1 2015

Short term...(today and tonight)
issued at 524 am EST Tuesday Dec 1 2015

WV imagery and rap analysis indicated a cutoff middle/upper level low
centered over southeast South Dakota. A shortwave trough ahead of the low
supported a band of mainly rain through northern Upper Michigan as an elevated
warm layer persisted with 925-850 mb warm air advection. With surface temperatures over the
higher terrain in the west at or only slightly above freezing...the
rain has resulted in icy conditions on untreated surfaces. The next
batch of precipitation associated with the main area of 700-300 mb qvector
conv ahead of the middle level low was moving through central and southeast WI.

Today...after the initial round of precipitation...there may be lull before
precipitation increases again from south to north across Upper
Michigan...especially between 14z-18z as an area of strong 800-600
mb fgen advances through the County Warning Area. Models suggest that the temperature
profile will favor mainly snow as colder air eliminates the warm
layer. With quantitative precipitation forecast amounts around 0.25 inch and relatively low slr
values in the 8/1-10/1 range snowfall amonts in the 1 to 3 inch
range are expected over mainly the higher terrain locations west of

Tonight...with the dry slot moving in...probability of precipitation will diminish with
mainly dry weather over much of the County Warning Area. As the middle level moisture
deaprts...except from iwd-cmx-p59...expect -dz to -fzdz as surface temperatures
drop. With the surface trough remaining over Western Lake
additional lake enhancement is expected as light SW winds prevail.
Any additional snow amounts over the west will remain lessthan a half

Long term...(wednesday through monday)
issued at 452 am EST Tuesday Dec 1 2015

Expect a slow and steady warmup each afternoon through the first
half of the weekend.

Will start out Wednesday morning with the 500mb low over the southeast half
of WI...and an elongated surface low stretching from southeast WI and S Lake Michigan
through Lake Superior to the Ontario/Quebec border. As the day rolls
on the elongated area of low pressure will exit east...lingering over
far East Lake Superior and east lower Michigan by 00z Thursday. The focus for
lingering precipitation will move into west Upper Michigan and weaken. Favorable
upslope north-north-northwest winds do not come into play until 21z. Even then 850mb
temperatures are only marginally cold at -4 to -5c and moisture looks to be
trapped below 800mb and diminishing. The dgz is way up around 600mb.
Can/T rule out up to an inch of new snow around iwd...but other
locations should expect less. Inversion heights continue to fall to
around 900mb by daybreak Thursday. The main concern will be limited
ice crystals...with the potential for freezing drizzle to continue
into the late morning hours over the west half...inland from Lake
Superior. Continue to mention the slight chance of freezing drizzle
in the severe weather potential statement.

Otherwise...look for improving conditions with dry weather taking
hold early Thursday morning through the start of the next work week.
There are a couple of periods of note...where the east could get
clipped by light snow showers Thursday night...and more of a mix
Saturday night as low pressure systems track well to our north /across
Hudson Bay/...temporarily suppressing the surface ridge overhead. The
high will shift to our east...from the lower MS valley through the
lower Great Lakes by the end of the day Friday...allowing warmer air
to surge into our area ahead of the next Canadian low. Expect highs
on Friday in the low to middle 40s...and in the middle to upper 40s
Saturday /warmest over the favorable downslope areas along Lake

Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1218 PM EST Tuesday Dec 1 2015

IFR/LIFR ceilings are expected through this evening. The best chance for
some improvement will be later in the evening at saw...when some
drying will arrive from the southwest on the southern flank of low
pressure departing into Ontario. Otherwise ceilings in the IFR to low
MVFR range will linger at iwd/cmx.

Marine...(for the 4 am Lake Superior forecast issuance)
issued at 542 am EST Tuesday Dec 1 2015

East-southeast winds to 30 knots today will gradually diminish as a trough
weakens and lifts into Western Lake Superior. Generally light winds
below 20 knots will then prevail through Wednesday night. SW winds to 30
knots veering to the west and northwest are possible Thursday as a trough moves
through northern Ontario. Winds are then expected to remain at or below
25 knots through Saturday.

MQT watches/warnings/advisories...
Upper Michigan...
Lake Superior...
Lake Michigan...


Short term...jlb
long term...kf

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