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Area forecast discussion 
National Weather Service Marquette Michigan
636 PM EST Sat Nov 28 2015

Short term...(this evening through sunday)
issued at 229 PM EST Sat Nov 28 2015

A sunny day has been experienced across Upper Michigan today except
for near the northern tip of the Keweenaw where some lake effect
clouds have been occurring under southwesterly flow. These lake
effect clouds are under the low inversion around 2-3kft and where
900mb temperatures are around -6c...out ahead of the approaching trough in
northwest Ontario. Ahead of the trough...saw some gusts over Lake
Superior to 30-33kts this morning and even up to 27kts at kcmx.
Those gusty winds have been making it feel cooler than the 32 degree
temperatures over the Keweenaw...with wind chill values aright
around 20. Elsewhere...2pm temperatures are in the upper 20s and
lower 30s with lighter winds.

The cold front will slide southeast across Lake Superior tonight and
shift winds around to the north late tonight but overall will be
fairly light. Upstream...low clouds and some light snow can be seen
in northern Ontario...which leads to increased confidence in the low
clouds expected late tonight into Sunday. Models fairly consistent
on these low clouds moving into the Keweenaw after midnight and then
sliding south across the northern tier of counties through the rest
of the night. Although winds are fairly light in the cloud
layer...the latest trends in the models have the clouds covering
much of the County Warning Area by middle Sunday morning...except for southern
Menominee County. Will continue to show that idea for the forecast
with mostly cloudy to cloudy skies over much of the area. Since
900mb temperatures will be a couple degrees colder tomorrow morning
than today...think the lake will help support the extensive cloud
cover. That lake help will also lead to the potential for some -shsn
or maybe even -fzdz. The biggest question for precipitation type is how low
the clouds will be and tied to the resulting forcing.
NAM...which tends to over do low level showing
ceilings only around a few hundred feet off the ground. That would
put a lot of the forcing at or warmer than -5c and increase the
potential for -fzdz. The GFS on the other-hand...has the cloud bases
in the 1-2kft...which would limit the cloud depth and at the same
time put the clouds more in the ice nucleation area. Believe the
precipitation will primarily be snow but couldn/T completely rule out the
-fzdz and added that with the slight chances of snow. Less upslope
flow over the Keweenaw leads to lower confidence on snow
showers...but did include flurries with the lake support in that

Long term...(sunday night through saturday)
issued at 320 PM EST Sat Nov 28 2015

Split flow will remain in place across the continent through much of
the week. Other than the system on Tuesday...expect the weather to
be quiet and fairly mild for the upper Great Lakes.

On Sunday night...any remaining drizzle/flurries and low clouds
should end as the surface ridge axis moves across the area. In
fact...there may be some clearing skies with the winds backing to
light out of the southwest and precipitable water values remaining
round 0.25 inch. If this occurs...temperatures across the interior will
likely drop into the lower teens.

Monday will be a transition day across the area. Upper ridging ahead
of the low over the plains will allow for a quiet day across the
entire northern Great Lakes. High level moisture will stream into
the region later in the day bringing some high clouds across the
area...however with 850mb temperatures around +2c...most areas should see
high temperatures well into the 30s or even some lower 40s across the

The upper low moves into the middle-upper MS valley on Monday night.
With the blocky nature of the trending toward the slower
GFS solution with regards to precipitation across Upper Michigan. In
fact...with the slower movement combined with the dry antecedent
conditions across the region...would not be shocked to see
precipitation hold off until Tuesday for the east half of the Upper
Peninsula. As such...will trend toward a GFS/European model (ecmwf) blend. Will still
bring likely probability of precipitation to the southern and western tier overnight on
Monday...with the entire forecast area with likely probability of precipitation on Tuesday.
With the short wave moving around the base of the trough
Tuesday...expect some drying to occur Tuesday afternoon across the south and have
reduced probability of precipitation to chance across that region. With the low track moving
overhead...would expect some terrain enhancement across the far west
due to the cyclonic upslope flow as well. As thinking northwest
WI and far west Upper Michigan will see the most precipitation with this storm.

Precipitation type will be the big problem with this system. Not
much in the way of cold advection with this system due to the
occluded and closed off nature of the upper low. Just enough cold
air aloft to likely keep much of the west half away from Lake
Superior all snow through the event...although the snow will be
extremely wet and heavy. As for the areas closer to Lake Superior
and to the east...the precipitation type will be highly dependent on
surface it seems like precipitation may start as snow across the
east but change over to rain by Tuesday afternoon as surface temperatures warm. Due to
the wet and heavy nature of the snow...could see some tricky travel
on Tuesday morning across the west. As for storm total accumulationsday
Monday night through Wednesday thinking the far west could
see snowfall of 4-7 inches...with the central u.P. 2 to 4 inches. An
inch or less Tuesday night across the east.

As the low departs to the NE Tuesday night...expect wrap around precipitation to
persist across Upper Michigan...especially across the west where the best
moisture will be located. With 850mb temperatures only around not
expect much lake enhancement...although there could be some terrain
enhancement with the cyclonic northerly flow. Small chance probability of precipitation Wednesday
across the east as the low continues to depart. Otherwise...the
remainder of the week should be very quiet with temperatures above
normal. In Saturday the GFS and European model (ecmwf) suggest strong
ridging across the central US and Great Lakes by Saturday. Would not
be shocked to see temperatures in the 40s on Saturday with strong SW flow.
Regardless...the end of the week should be precipitation free.

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 634 PM EST Sat Nov 28 2015

A dry west slowly veering northwest flow of air will bring VFR conditions to the
taf sites most of tonight. But as the flow veers toward the north later
tonight and then the east-northeast on area of low clouds now in northwest Ontario
will sink S into Upper Michigan and result in predominant MVFR ceilings first at
cmx and then at saw. Since the expected flow on sun will downslope
into iwd...that location is likely to avoid the low clouds altogether.
Not out of the question there could be some flurries at cmx and saw
as well...and even some -fzdz at saw with a more favorable upslope
wind direction that could cause some borderline IFR ceilings there...
but this precipitation will not result in a sgnft visibility restriction if it

Marine...(for the 4 PM Lake Superior forecast issuance)
issued at 229 PM EST Sat Nov 28 2015

After gusting to a little over 30kts from the southwest this
morning over Western Lake Superior ahead of an approaching
trough...expect winds to diminish and shift to the north tonight.
Winds will slowly veer through the day on Sunday and remain
light...returning to the south Sunday night. A ridge will keep
winds light into Monday...but expect them to increase Monday night
into Tuesday...out of the east-southeast...ahead of an approaching
low pressure system. At this time...not expecting any gales as the
low moves through the region...but gusts to 30kts are possible as
the low nears on Tuesday. Behind the low...winds will shift to the
north-northwest to 25kts and then quickly diminish as a ridge
builds over the area.

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


Short term...srf
long term...mrd

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