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Area forecast discussion 
National Weather Service Grand Rapids Michigan
1200 am EST Friday Nov 27 2015

Latest update...

issued at 300 PM EST Thursday Nov 26 2015

Periods of rain overnight with temperatures remaining in the 50s.
Rain will end from north to south on Friday as a cold front pushes
through and south of the region. Temperatures will fall to around
40 by sunset as winds begin to blow briskly at times out of the
north. No travel concerns for the remainder of the weekend as fair
weather with seasonable temperatures takes over Friday evening
and continues through the Monday. A new storm will approach from
the Mississippi Valley late Monday with mainly a rain threat into


issued at 1002 PM EST Thursday Nov 26 2015

Updated to boost min temperatures a few degrees south of a Holland to
Alma line. The cold front to the west likely won't move much past
that line prior to temperatures should remain mostly in the 50s
across the southern County Warning Area.


Short term...(today through Saturday night)
issued at 300 PM EST Thursday Nov 26 2015

Overall forecast on track with over an inch of rain expected north
and west of a Holland to Montana pleasant line by late tonight with
0.50 - 1.00 inches to south and east through Friday midday. Would
expect to see some large puddles and swollen small streams and
rivers with the higher rainfall north and with combo of rain and
remaining snowmelt south...but only minor impacts expected at this

Latest nwp guidance has slowed the progression of the front
through the area down by 3 to 6 hours and so rain will also linger
a bit longer ending steadily from north to south Friday morning.
Rainfall supported by deep convergence of 50+ knots low level jet into strong
frontal zone. Weak frontal wave moving from northeastward from central Iowa
will slow front a bit this evening resulting in the heaviest
rainfall across the northern half of the area.

Expect some enough drying with cold air advection Friday
afternoon and evening to inhibit any black ice as temperatures
drop a bit below freezing by Saturday morning. You may however
want to hold off on heading out to cut-down the xmas tree until
next weekend as the mud will likely be thick at The Farms Saturday
and Sunday.

Long term...(sunday through wednesday)
issued at 300 PM EST Thursday Nov 26 2015

Upper ridging over the eastern U.S should keep the region dry
Sunday and early Monday with near normal temperatures. However we should
turn wet into Monday night and Tuesday as a stacked low moves into
the western Great Lakes. Good agreement that the surface low
remains to our west...keeping SW Michigan in the warm sector...keeping
precipitation type all rain. Colder air wraps in behind the system Tuesday
night and Wednesday...leading to a change to snow. At this point
it appears any snow accums would be light.

Chilly air stays put Wednesday and Thursday with northwest upper
flow. However the area should dry out by Wednesday night/Thursday
as the air should not be cold enough for lake effect...and a surface
high builds into the western Great Lakes.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1200 am EST Friday Nov 27 2015

MVFR conditions will give way to IFR overnight as steady rain
moves in. The IFR will persist until after 12z then improve to
MVFR...finally coming up to VFR Friday evening. Winds will gust
over 20 knots at times tonight and Friday morning. Winds will
swing from southwest to north as the cold front moves through


issued at 300 PM EST Thursday Nov 26 2015

No changes this afternoon with Small Craft Advisory continuing through Friday
night based on wave heights at or above 3 feet. Gusty south winds will
become northwesterly Friday and cold air advection will cause waves to
remain hazardous to small craft.


issued at 150 PM EST Thursday Nov 26 2015

A Flood Advisory has been issued for the Sycamore Creek at Holt. An
ncrfc minimum ensemble quantitative precipitation forecast scenario even suggested a rise above
bankfull at Holt. The current forecast has a crest around 6.8 feet
Saturday afternoon. Above 6.0 feet...flooding begins in low lying
areas along the creek and at Lansing Municipal Golf course and Scott
Woods Park.

All of southwest lower Michigan will receive additional rainfall
this afternoon through Friday afternoon...with the highest amounts
toward Muskegon...Ludington...and Big Rapids. Fortunately...these
areas have seen the least runoff from snow melt. Minor flooding will
be possible this weekend...mainly in low lying areas near creeks and
streams. Additional ponding in urban areas will also be possible.

The Maple River near Maple Rapids may also approach bankfull...but
confidence is not high enough to issue a river Flood Advisory at
this point. Friday night through Monday looks dry with high pressure
in control. Additional precipitation is expected Monday night
through Tuesday.


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



short term...dkc
long term...jk

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