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Area forecast discussion 
National Weather Service Gaylord Michigan
120 PM EDT sun Aug 30 2015

issued at 1014 am EDT sun Aug 30 2015 with stratus. Low clouds were widespread in southeast sections
(s of Mio and east of lake city)...and in central/eastern Chippewa
and eastern Mackinac. Less widespread stratus was seen along the
Lake Michigan coastal counties of northwest lower Michigan. Meanwhile...places north and
east of glr were enjoying a sparkling morning. These clouds had not
yet started to appreciably erode as of the most recent visible Sat
image (945am). That process will get started shortly...but in the
meantime...have had to crank up cloud cover through early- and even
middle-afternoon in parts of northwest lower and eastern upper. (Forecast
already had considerable cloud cover through the day in southeast sections).
Maximum temperatures will also adjusted slightly downward in these areas.


Near term...(today through tonight)
issued at 400 am EDT sun Aug 30 2015

Broad area of surface high pressure extends from the Great Lakes
region SW into the middle and upper Mississippi Valley and into the
Central Plains early this morning. 500 mb trough remains just south
of our County Warning Area...extending from Southern Lake Huron through Southern Lower Michigan.
Patches of low clouds remain over far southern and far northern sections of
our County Warning Area. In between...clearing skies...calm winds and lingering
shallow low level moisture have lead to the development of fog and
low stratus.

Expect areas of fog and low stratus will continue to gradually
expand below the building subsidence (and nocturnal) inversion through
early morning. Once diurnal mixing begins...fog and low stratus
should begin to mix out into a broken and eventually scattered cumulus deck as
increasingly drier air aloft mixes with and eventually erodes any
residual shallow low level moisture. Greatest cloud cover should be
across our southern County Warning Area where low level moisture will hold on for a bit
longer than the rest of our County Warning Area. Under partly to mostly sunny
skies...high temperatures this afternoon should rebound nicely into the middle
70s to around 80 degrees.

Loss of any diurnal instability and strengthening subsidence will
lend to clearing skies this evening. As winds again become calm
directly under the surface high center...some patchy fog will again
develop...but should be not as widespread and thick as this morning.
Overnight lows will fall into the upper 50s and lower 60s.


Short term...(monday through Tuesday night)
issued at 400 am EDT sun Aug 30 2015

..warmer and more humid this week...

High impact weather potential: minimal.

Pattern synopsis/forecast: large scale pattern amplifying in
response to strengthening trough/-pna teleconnection over the
eastern Pacific. This in turn in building heights across the
central u... there is some weakness in the flow downstream
of this ridge particularly along the eastern Gulf Coast. As an
aside interesting to watch the tropical cyclone train across the
Pacific basin with "kilo"..."ignacio"...and "jimena" all nicely
lined up roughly between 15-20n and churning westward. Surface high
pressure ridge runs west-east from the upper Midwest across the
Great Lakes to New England. Weak front stretches from Northern
Ohio/Indiana southwest into Oklahoma.

Overall large scale pattern will not change much for this part of
the forecast cycle. Upper level heights will be building into the
upper lakes to kick off September...though aforementioned weakness/
troughing in the pattern over the southeastern states/Gulf of Mexico
forecast to retrograde and linger over the Southern Plains and
possibly extending into the Mississippi Valley (already some
evidence of this occurring in early morning water vapor imagery over
texas). So there may be some trapped upper level energy within an
expansive area of ridging from the Southern Plains to the East Coast
early in the week. This will have to be monitored though with weak
flow over the central/southern U.S. Would think any of this would
have a difficult time having an impact on Michigan. Short wave
trough getting kicked out of the mean eastern Pacific long wave
trough will pass by well to the northwest Monday. Associated cold
front forecast to get stretched out in a northeast-southwest
orientation across northwest Ontario and back into the Dakotas...may
also be the tail end of a warm front across Lake Superior Monday
morning. This cold front will probably slide into Lake Superior at
some point Monday night/early Tuesday though weakening with time.

Primary forecast concerns: temperatures and increasing humidity
Monday/Tuesday. Potential for convection tuesday???

Monday...first day of meteorological fall certainly won't feel like
it. Rather quiet synoptically speaking with deep layer ridge axis
building into the upper lakes with 500mb heights at or above 588dm.
Any fog early should mix out leading to a good deal of sun...with
temperatures expected to warm into the 80s away from the immediate
lakeshores. Dew points will likely run from 60-65 so will feel
somewhat sticky Monday afternoon. Warm night expected Monday night
as well...early morning lows Tuesday expected to be in the 60s.

Tuesday...weakening cold front expected to reach Lake Superior/
western Upper Michigan Tuesday. Dew points will tick a little
higher which will add to the humidity...and also increases potential
for generating some instability especially along/ahead of the
boundary across northern Wisconsin/Upper Michigan. So some concern
about the potential for late afternoon/early evening showers/
thunderstorms across eastern Upper Michigan...will leave out of
forecast for now to cover "collaboration issues". Also a
possibility of some pop-up convection across interior northern lower
in increasingly humid air mass (perhaps aided by Lake Huron breeze).
Expect to see some locales up around 90 Tuesday afternoon.


Long term...(wednesday through saturday)
issued at 400 am EDT sun Aug 30 2015

Pattern synopsis/forecast: higher than normal heights (in the 588dm
vicinity) will be in place at the start of the extended range
Wednesday...and are forecast to persist through the remainder of the
week as eastern Pacific trough shifts inland. May still be some
lingering upper level disturbances with the mean trough position
over the southeast quadrant of the Continental u... a warm
pattern synoptically in the Wednesday-Saturday time frame.

Forecast trends: getting into hot territory Wednesday with more 90+
degree readings expected. Think at some point we're going to have
to deal with afternoon/early evening convection...although little to
focus on in the extended period to try and delineate which days are
more at risk. At the very least looking at an extended period of
very warm/humid weather through next weekend.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 120 PM EDT sun Aug 30 2015

Ceilings improving this afternoon. Stratus/fog returning late tonight.

Early morning stratus has lifted into a VFR to MVFR stratocu/cumulus
deck. Ceilings will continue to gradually improve as we move through the
afternoon. High pressure sits over the Ohio Valley and eastern
Great Lakes...with a slow increase in temperatures/moisture expected on
SW low-level winds. Stratus and/or fog will reform late
tonight...with MVFR to IFR conditions. Anticipate more in the way
of fog at pln...more in the way of stratus elsewhere. Conditions
will gradually improve middle-late Monday morning.

Light winds through the forecast.


issued at 400 am EDT sun Aug 30 2015

Winds and waves will remain below Small Craft Advisory criteria through Monday night
as high pressure currently overhead slowly slides southeast of Michigan.
Areas fog will impact the nearshore areas overnight into early
morning. significant weather is expected through early
week. Our next chance of precipitation will develop by middle week.


Apx watches/warnings/advisories...


near term...mlr
short term...jpb
long term...jpb

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