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Area forecast discussion 
National Weather Service Grand Rapids Michigan
1235 PM EST sun Feb 14 2016

Latest update...

issued at 328 am EST sun Feb 14 2016

High pressure moving east today will make way for low pressure to
move across the Midwest. Light snow will move across southwest lower
Michigan tonight and Monday although accumulations will be light.
After that system moves east another one moves in and light snow is
again possible Tuesday. Much warmer air is expected to move toward
the Great Lakes late in the week and highs well into the 40s are
possible along with some rain.


issued at 1129 am EST sun Feb 14 2016

I see no major changes in our ongoing forecast at this point. I go
get the impression this snow event will be very under whelming as
most of the moisture and dynamics for it go south of Michigan
tonight. As I wrote yesterday...this seems more than anything like
a weak warm advection lift event sort of thing.

Really we have to watch the 180 knot jet streak currently coming
on shore over the Pacific northwest.... there is a storm forecast
to just miss US to the south Wednesday. It is not out of the question
that storm could track farther north... we will need to be
watching this.


Short term...(today through tuesday)
issued at 328 am EST sun Feb 14 2016

Forecast concerns today deal with snow potential later today through

A weak area of low pressure will move southeast from the plains
across Iowa/Illinois/Indiana late today through Monday. Light will
develop ahead of the system and slowly move across the County Warning Area tonight
through Monday. Quantitative precipitation forecast is light and only an inch or two of snow is
expected. Given the light impacts of the system no headlines were
issued. There will be a brief lull in the precipitation Monday night and then
another system will follow a similar track through
Iowa/Illinois/Indiana. Light snow is again possible but less
certain. The NAM is quite a bit farther north with the system than
the GFS or European model (ecmwf) so chance probability of precipitation seem the way to go Tuesday.

After another cold day today with highs mostly in the teens...Monday
and Tuesday will feel balmy with highs in the middle 30s.

Long term...(tuesday night through saturday)
issued at 328 am EST sun Feb 14 2016

A cold front is prognosticated to move south through the area on Tuesday
night with perhaps a light dusting of snow associated with it. High
pressure moves in quickly behind this front and provides quiet
weather for Wednesday and Thursday.

Strong warm advection will be underway on Thursday night as a system
off the Pacific tracks across the northern plains. A brief period of
mixed snow/sleet and freezing rain related to isentropic lift north
of the warm front will be possible Thursday night before surface temperatures
warm quickly above freezing early Friday.

Rain showers... breezy conditions...and mild temperatures in the 40s
are expected Friday as the low tracks across the northern Great Lakes region.
It should dry out Saturday as the low pulls away... but temperatures
will remain above normal.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1235 PM EST sun Feb 14 2016

VFR conditions will continue into this evening. However an area of
snow will move over the region later this evening and MVFR with
occasional IFR will develop. This snow should arrive 02-04z and
linger the rest of the overnight and into Monday morning. The
snow is not expected to be the variable conditions...
from MVFR to IFR...will continue. The snow should end toward the
end of this forecast period...around 18z Monday.

South to southeast winds will remain brisk at 10-15 knots through
tonight...before diminishing toward daybreak Monday.


issued at 328 am EST sun Feb 14 2016

Wind and wave will remain below advisory criteria today. Winds will
increase tonight and a Small Craft Advisory may be needed.


issued at 328 PM EST Sat Feb 13 2016

River gauges throughout southwest lower Michigan continue to show
signs of being affected by ice formation. A confirmed ice jam was
reported along the Grand River near Comstock Park...causing the
river to rise there. The ice is jamming at North Park bridge.
River ice will continue to increase in coverage as well as
thickness through Sunday night. Rapid fluctuations in river level
will be possible wherever ice jams occur. We will need to monitor
river level trends closely.

Temperatures will peak in the low to middle 30s on Monday... which
should halt ice formation.


GRR watches/warnings/advisories...


short term...04
long term...Meade

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