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Area forecast discussion 
National Weather Service Grand Rapids Michigan
617 am EST Thursday Mar 5 2015

Latest update...

issued at 302 am EST Thursday Mar 5 2015

Winter will relax its grip on west Michigan over the next week.
Today will be cold though with highs in the teens. A warm up will
start Friday that will carry into next week when highs reach the middle
40s. A few light snow showers are possible over west Michigan
through Sunday then mainly dry weather until the end of next week.


Short term...(today through saturday)
issued at 302 am EST Thursday Mar 5 2015

Forecast concerns are minimal this morning. Main adjustment to the
forecast was to trim probability of precipitation near the Lake Shore today.

The prospects for snow showers are not great...but not quite zero
either. High pressure is nosing into west Michigan and will help to
keep much of the County Warning Area dry today. Can't rule out a shsn...but nothing
organized expected. Today will be cold. Highs in the teens expected
as 800 mb temperatures in the lower -20s move across. Winds will turn to the
southwest tonight ahead of the next trough and temperatures will begin to
warm. Winds will increase Friday. So although temperatures will be
warmer...apparent temperatures will remain cold. Can't rule out a few shsn
either as a trough drops south from Canada. Scattered shsn will linger
into Saturday. No accums expected. Saturday could feel downright
balmy with highs in the middle 30s.

Long term...(saturday night through wednesday)
issued at 302 am EST Thursday Mar 5 2015

Pretty quiet in the extended with only a weak clipper coming through
Sunday and Sunday night with some light snow...which may cause some
slippery roads for the Monday morning commute. Milder weather
follows for Tuesday and Wednesday as the large scale flow GOES
zonal and the polar jet retreats at least temporarily to southern
Canada for the first time in several weeks.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 617 am EST Thursday Mar 5 2015

VFR conditions expected through Thursday. Light lake effect snow
showers could bring periods of MVFR to areas near Lake Michigan
such as mkg. North wind at or below 10 knots today going west or southwest
by this afternoon.


issued at 330 PM EST Wednesday Mar 4 2015

Snow water equivalent values are estimated to be around an inch near
the headwaters of the Grand River in Jackson County. Swe values
increase to around 2 inches in Lansing and Grand Rapids. Swe values
of 3+ inches are possible in Ottawa County. Similar story along the
Muskegon river with swe values around 2 inches in Big Rapids
increasing to 3-4 inches closer to the Lakeshore. A Big Warm up in
addition to a 1-3 inch rainfall event...for example...would
certainly mean flooding concerns.

With very cold temperatures in place tonight through
significant ice breakup is expected. Ice jam potential is fairly
low. The latest models continue to indicate a warming trend this
weekend and especially into next week. Highs generally in the middle
30s are expected this weekend increasing to the upper 30s to lower
40s early next week. The north central river forecast center
indicates there is a medium risk for a break-up ice jam for the
Grand River near Robinson township. A break-up ice jam is likely
this month...but not in the next 7 days.

However...according to the climate prediction center...there is a 60
percent chance for above normal temperatures March 11-17. Highs in
the 40s and 50s seem attainable next Wednesday and Thursday.


GRR watches/warnings/advisories...


short term...04
long term...ostuno

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