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Area forecast discussion 
National Weather Service Grand Rapids Michigan
328 PM EDT Friday Mar 27 2015

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

issued at 328 PM EDT Friday Mar 27 2015

It looks like winter isn't quite done with west Michigan yet.
Saturday will be dry but mixed rain and snow will arrive Sunday
potentially putting down an inch or so of snow mainly north of Grand
Rapids. Temperatures will warm into the middle 50s by middle week


Short term...(this evening through Sunday night)
issued at 328 PM EDT Friday Mar 27 2015

Forecast concerns continue to be the potential for snow Sunday.

The 12z models are a bit slower than yesterday/S models visible a visible
the cold front moving through Sunday. At this time...the
European model (ecmwf)/GFS/NAM are in good agreement that precipitation will begin closer to
noon across the County Warning Area rather than earlier Sunday morning. We looked at
forecast soundings from north to south over the County Warning Area and it certainly
appears as though precipitation will begin as a brief period of snow and then
mix with then change to rain over most of the County Warning Area. The northeast 6
counties plus Montcalm may see light snow persist a bit longer. Even
there though with temperatures climbing toward 40 late in the day the
accumulation potential looks limited. It's possible some of the
higher elevations could see an inch or two but other locations may
not see much more than a few tenths. Driving this system is a
compact but fairly strong short wave that moves across the County Warning Area
Sunday afternoon. Soundings are very dry initially with this system
which will lead to evaporative cooling of the column but lift from
the short wave will aid in precipitation development. The precipitation will diminish
Sunday night as the short wave moves east.

Outside of Sunday...tonight looks very cold as winds diminish and
skies clear. Temperatures should fall to near 0 over the northern County Warning Area and
teens elsewhere.

Long term...(monday through friday)
issued at 328 PM EDT Friday Mar 27 2015

Northwest flow aloft will continue over the Great Lakes through
Tuesday before zonal flow develops middle week. That means that temperatures
will start off in the 40s and lower 50s Tuesday then climb to near
60 by next Friday.

As zonal flow develops we expect to see an increase in systems
moving over the Great Lakes and this occurs during the ling term. A
compact little clipper is forecasted to move across the southern County Warning Area Monday
night and Tuesday bringing mixed rain and snow to the County Warning Area. Then
light rain Wednesday night when a weak cold front moves through.

A bigger storm with influence from the southern stream will affect
the County Warning Area Friday. As low pressure develops over the middle Mississippi
Valley a south flow from the Gulf will push warmer air into the
Great Lakes. We/ll likely see rain develop early Friday and continue
through the day. It/S possible that wet snow could mix in with the
rain north of M-46 but that/S not certain yet.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1246 PM EDT Friday Mar 27 2015

Limited aviation concerns the next 24 hours...with VFR conditions
expected throughout the period. The main item of note will be
gusty north winds this afternoon in the 12 to 25 knot range. The
winds will subside quickly as we move through sunset this evening.
Light winds are expected overnight and on Saturday.

Lake effect clouds will occur in northerly flow into tonight...but
that will keep though to the east and west of the southwest lower
Michigan taf sites.


issued at 1246 PM EDT Friday Mar 27 2015

Rivers are comfortably below bankfull and are holding steady or
slowly falling. The Wednesday system had little if any impact on
river levels. Precipitation on the way for Sunday will generally
amount to less than Wednesday... so flooding is not a concern.


GRR watches/warnings/advisories...


short term...04
long term...99

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