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Area forecast discussion 
National Weather Service Gaylord Michigan
1250 PM EST Wednesday Nov 25 2015

issued at 1249 PM EST Wednesday Nov 25 2015

So far, nothing to change in the current thinking as we are well
in the warm sector with the strong southerly flow out ahead of the
surface low and cold front that is approaching the region. Clouds on
satellite images have been mainly thin middle to high level clouds
with lower clouds in Wisconsin. Rain is expected to develop and
move into the region overnight tonight. Rain is developing on the
kgrb under the lower clouds in Wisconsin. So will watch the timing
and movement of this area. Otherwise, the only other returns, have
been middle-level returns that haven't been hitting the ground yet.

Update issued at 943 am EST Wednesday Nov 25 2015

Main concern for the forecast aren't until tonight, when the front
and the surface low that is in the northern plains, begin to move into
the upper Great Lakes. Will be watching the timing of the rain as
it gets closer. A few of the hi-res short term models suggest that
there could be rain chances before 00z. However, the bulk of the
rain still looks like it will begin to affect the forecast area,
after 00z, with most of that after 03z. So far, no changes in the
next 6 to 12 hours with dry, mild weather expected.


Near term...(today through tonight)
issued at 353 am EST Wednesday Nov 25 2015

..nice day today with light rain arriving tonight...

High impact weather potential: reduced visibilities in fog

Pattern synopsis: current surface analysis shows high pressure
encompassing the East Coast...and Lee troughing spanning the High
Plains. Increasing southerly boundary layer flow in between these
features across the nation's midsection. A warm front extends
southeast from a 1006mb low over South Dakota...across southern
Iowa/central portions of Illinois and Indiana. Narrow axis of Gulf
return flow up into Texas/central portions of Oklahoma/Kansas. Low
amplitude short wave ridging was over the upper Mississippi Valley/
northwest Ontario...downstream of the southern branch of a split
positive tilt upper trough over the northern rockies/Pacific
northwest. Deep layer warm advection across the Midwest/upper Great
Lakes associated with the rising heights and a 40kt south-
southwesterly low level jet. Skies were still cloudy across much of
the Upper Peninsula early this morning...with clear-partly cloudy
skies below the bridge and areas of fog over eastern lower Michigan
(south of the M-72 corridor).

Pattern forecast: Michigan will remain firmly entrenched in
southerly return flow this forecast period...with surface low over
South Dakota tracking northeast into northern Ontario during the day
today. A cold front will lie across the upper Midwest/Central
Plains by early evening...with Gulf moisture gradually getting
pulled northward ahead of this front through the day. This front
will advance east into Upper Michigan/Wisconsin later tonight.

Primary forecast concerns: winds today...chances for precipitation
breaking out ahead of the cold front across Michigan later tonight.

Today...fairly benign looking day on tap...with partly-mostly sunny
skies expected with a little more cloud cover across Upper Michigan
than farther south. Will be a breezy day with south/southeast
winds...some good momentum not far off the deck (30-40+kts above 1k
feet agl) but strong warm advection will limit how efficiently we'll
be able to tap into that. Gusts 15-30mph seem reasonable for
now...will be strongest along the South Shore of the Upper
Peninsula...and along the northwest lower shoreline. Despite
limited mixing due to the warm advection...expecting temperatures
several degrees above average this afternoon with widespread highs
in the 40s.

Tonight...return flow moisture transport will be aimed at northern
Michigan starting this evening...with a thicker layer of cloud cover
associated with this moisture feed and isentropic ascent spreading
across the forecast area early on. Initial moisture surge will be
primarily below 700mb...and thus initial upper cloud layer
temperatures are expected to be warmer than -10c. So not a lot of
ice processes at the onset so more of a misty light rain is more
common with this type of vertical moisture/temperature distribution.
Rainfall totals for tonight generally from 0.05-0.15 inch expected
with higher amounts across eastern upper/northwest lower where rain
will start sooner. Saturating lower layers and advection of above
freezing dew points over leftover snow cover will promote fog least across the higher terrain of northern lower
and probably across parts of eastern upper/northwest lower.


Short term...(thursday through Friday night)
issued at 353 am EST Wednesday Nov 25 2015

High impact weather: locally dense fog possible Thursday. Roadways
may become slick Friday morning as temperatures fall below freezing
with wet roads already wet.

This forecast period will begin with widespread rain over the entire
forecast area. This precipitation will be generated from a low
pressure system over Ontario extending south into the Mississippi
River valley. This low pressure system along with a large area of
high pressure over the eastern Seaboard of the United States is
generating southerly flow...ushering in milder temperatures and
plenty of moisture. Most precipitation will fall as rain Thursday
and Thursday night. Rain doesn't start mixing with or changing to
snow until after frontal passage late Thursday night over eastern
upper and then early Friday morning over the rest of the County Warning Area. Most
of the quantitative precipitation forecast will have fallen in the form of rain ahead of the cold
front...which in turn will only generate light snow accumulations...
if any...with the highest amounts of 1 to 2 inches over eastern
upper and the higher terrain of northwest lower Michigan.
Elsewhere should only see an inch or less. Models have been fairly
consistent with quantitative precipitation forecast amounts of over an inch when this event is all
said and done by Friday night. Although there won't be much
accumulations...the temperatures dropping below freezing Friday
morning may create very slick roadways. Precipitation will end
Friday afternoon across eastern upper and the tip of the mitt
counties and during the evening across the far southeastern County Warning Area.
Northerly winds will be gusty after frontal passage Friday with
cold air advection making it easier to get stronger winds down to
the surface...especially areas along the Lake Michigan shores of
northwestern lower. A large area of high pressure and very dry air
will build rapidly behind the departing system...providing
northern Michigan with mostly clear skies Friday night and
Saturday. With clear skies and fairly light winds low temperatures
will drop into the teens to low 20s Friday night/Saturday morning.
While daytime temperatures will be in the middle 40s north to near 50
over the far southern part of the County Warning Area...and only reach into the
30s behind the front Friday and Saturday.


Long term...(saturday through tuesday)
issued at 353 am EST Wednesday Nov 25 2015

High pressure will continue to dominate northern Michigan's weather
through at least Monday...providing partly cloudy skies. Models seem
to have slowed the progression of the next storm system that
develops over the western Great Lakes a bit. Still expect increased
cloudiness Monday ahead of this system and precipitation chances
increasing late Monday/early Tuesday morning and lasting through the
end of the forecast period. Daytime temperatures in the upper 30s to
near 40 and cold nights in the upper teens to 20s.


Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1244 PM EST Wednesday Nov 25 2015

Not much of a change over the previous forecast as there will
continue to be VFR conditions over the region, until tonight, when
the cold front approaches the region and begins to produce rain.
Ahead of the front, a strong low level jet and little mixing at
the surface will produce low level wind shear, through at least

As the rain moves in, the ceilings are expected to fall to IFR, and
probably LIFR categories in both visibility and ceilings. This will continue
through at least 18z/Thursday as well.


issued at 353 am EST Wednesday Nov 25 2015

Increasing south/southeast winds through the morning within all
nearshore zones...winds that will continue through the afternoon.
Small Craft Advisory conditions for certain expected...maybe some
low end gales on Northern Lake Michigan though mixing into higher
momentum aloft will not be particularly efficient. But winds in
excess of 35kts not far off the deck. Winds will veer to the
southwest later tonight and start to diminish as gradient weakens in
advance of an approaching cold front. Lighter winds expected
Thanksgiving day as winds continue to swing around to the
north/northwest with passage of a cold front....with increasing
winds Thursday night into Friday.


Apx watches/warnings/advisories...
LH...Small Craft Advisory until 7 am EST Thursday for lhz345>349.

Lm...Small Craft Advisory until 7 am EST Thursday for lmz323.

Gale Warning until 1 am EST Thursday for lmz341-342-344>346.

Ls...Small Craft Advisory until 7 am EST Thursday for lsz322.

Gale Warning until 1 am EST Thursday for lsz321.



near term...jpb
short term...tjl
long term...tjl

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