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Area forecast discussion 
National Weather Service Grand Rapids Michigan
635 PM EST Friday Nov 27 2015

Latest update...

issued at 305 PM EST Friday Nov 27 2015

Any left over showers will come to an end by late evening as a
large high pressure system continues to feed cooler and drier air
in the region. This large high pressure system will bring
considerable sunshine with seasonably cool temperatures through
the weekend. Another storm system may bring rain and possibly a
little snow to the area by the middle of next week.


Short term...(this evening through Sunday night)
issued at 305 PM EST Friday Nov 27 2015

What we area watching for tonight is outside chance of a little
freezing drizzle/ light rain south of Interstate 94. Otherwise I
expect slow clearing tonight and considerable sunshine Saturday
and Sunday.

A southern stream shortwave...tracking along the departing frontal
system will be just strong enough to push middle level moisture as
far north as Interstate 94 overnight. As that is happening a very
shallow layer of cold air (less than 2000 feet in depth base on rap
model soundings) will continue to feed southward across all of
lower Michigan. There is just the outside chance air... cold
enough to cause freezing light rain/drizzle... will be there
later this evening. Seems to ME the odds are currently to low to
actually put this in the forecast.

Once that shortwave moves out of the area a large high pressure
system moves in and only slowly moves eastward out of the Great
Lakes by early next week.

Long term...(monday through friday)
issued at 305 PM EST Friday Nov 27 2015

A weak low pressure system will bring a chance for a few light rain
showers beginning Monday afternoon. A better chance for rain showers
will come Monday night and Tuesday as the surface low moves across the
northern Great Lakes region and a cutoff upper level low drifts
slowly east across our region Tuesday through Wednesday.

Precipitation will become mixed with then change over to scattered
light snow showers and flurries Tuesday afternoon and evening as
cooler air moves in. Light lake effect snow showers will likely
develop later Tuesday night through Wednesday when 800 mb temperatures will
fall to -6 to -8 c yielding Delta T/S in the middle teens. Some
light lake effect snow accumulations are possible in that time

A high pressure ridge will build in to produce fair weather Thursday
through Friday. Temperatures will average at least five degrees above
normal through most of the long range forecast period.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 635 PM EST Friday Nov 27 2015

MVFR conditions will prevail overnight with IFR early this evening
across southern far Southern Lower Michigan. Conditions will
improve to VFR by 18z Saturday. Winds will be north around 10


issued at 305 PM EST Friday Nov 27 2015

Northeast winds of 15 to 25 knots will allow our Small Craft
Advisory to continue as forecast for this evening...beyond that
winds will diminish overnight and being from the northeast that
will also allow the wave height to by morning our
Small Craft Advisory should be allowed to expire as forecast
around 6 am.


issued at 305 PM EST Friday Nov 27 2015

Widespread rainfall has ended...but minor flooding remains a concern
through the weekend...mainly in low areas adjacent to streams and
creeks. In particular...the Sycamore Creek near Holt and the pere
Marquette river near Scottville could rise slightly out of their
banks over the weekend...but should not approach flood stage.
Swollen creeks and streams will begin to fall again by early next

After a dry weekend...rain returns Monday evening through Tuesday
before changing over to snow. Rainfall totals should remain around a
half inch or less. Accumulating lake effect snow is possible Tuesday
night into Wednesday over portions of western lower Michigan.


GRR watches/warnings/advisories...
Lm...Small Craft Advisory until 6 am EST Saturday for lmz844>849.



short term...wdm
long term...Laurens

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