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Area forecast discussion 
National Weather Service Grand Rapids Michigan
328 am EST sun Nov 29 2015

Latest update...
synopsis/short term/long term/marine

issued at 328 am EST sun Nov 29 2015

High pressure over Quebec will provide plenty of sunshine across
southwest lower Michigan today and Monday. Low pressure moving north
toward Minnesota will spread showers into lower Michigan late
Tuesday. Snow may mix in with the rain Tuesday night and Wednesday
but little if any accumulation is expected.


Short term...(today through tuesday)
issued at 328 am EST sun Nov 29 2015

Forecast concerns are minimal and deal with precipitation from the storm that
will move from the plains north toward Minnesota Tuesday. Before
that precipitation develops though we do see some clouds moving toward lower
Michigan at this time that are not being handled well by the models. The
clouds are associated with a weak upper wave that is moving along
the Ohio Valley. It/S possible that some of these clouds will move
over the southern County Warning Area later this morning before the wave we boosted the sky grids accordingly.

Generally clear skies tonight and Monday. Then the plains storm that
moves north toward Minnesota. This is a pretty dynamic low that
pushes a occluded front through the County Warning Area Monday night. Showers will
develop along the frontal boundary Monday evening and move through
the County Warning Area Monday night. 800 mb temperatures quickly fall to -4c over the lake
Tuesday afternoon. Low level moisture may be lacking then.
However...given the upper low moving over the County Warning Area...we could see a
few snow showers develop but no accumulations expected.

Long term...(tuesday night through saturday)
issued at 328 am EST sun Nov 29 2015

Main focus of the long term continues to be on the chances for snow
Tuesday night and Wednesday as an upper low traverses the region.
The upper low remains in the west...seen spinning this morning over
Nevada/Utah in water vapor imagery. The upper low will bring some light
snow to the area and aid in the development of lake effect snow
showers Tuesday night and Wednesday. The European model (ecmwf) and the GFS bring a
cold pool of air through the Great Lakes which should produce Delta
T/S in the middle teens. We are looking at some light accumulations
of snow in the western half of the forecast area as winds shift from
SW to northwest with the passage of the low. There could be some banding in
the lake effect snow Tuesday night into Wednesday morning
especially...which could produce some locally higher accumulations.

Beyond Wednesday...have a dry forecast through Saturday as the area
will be in a split flow regime. Surface ridging should result in dry
weather with temperatures that will trend above normal. No
intrusions of polar/Arctic air seen in the long range data.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1150 PM EST Sat Nov 28 2015

VFR conditions will continue through Sunday evening. The exception
will be at jxn where light fog will reduce visibilities to the 3 to 5
mile range overnight.

Winds will be light and variable tonight and from the east less
than 10 knots on Sunday.


issued at 328 am EST sun Nov 29 2015

High pressure over lower Michigan will result in low wind and waves
today and Monday.


issued at 1230 PM EST Sat Nov 28 2015

The Flood Advisory continues for Sycamore Creek at Holt. Sycamore
Creek was cresting early this afternoon slightly out of its banks.
The pere Marquette river near Scottville and the White River near
Whitehall may crest around bankfull. The Maple River near Maple
Rapids will continue to slowly rise a couple more feet...but should
remain within its banks.

Dry weather is forecast through Monday. Light rain Monday night into
Tuesday should not have a significant impact on river levels.


GRR watches/warnings/advisories...


short term...04
long term...Duke

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