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Area forecast discussion 
National Weather Service Grand Rapids Michigan
728 PM EDT Sat Mar 28 2015

Latest update...

issued at 330 PM EDT Sat Mar 28 2015

High pressure will bring a quiet night to southwest lower Michigan
tonight. A cold front will sweep through the area on Sunday which
will bring rain and snow to the region. The precipitation should
come to an end Sunday evening. There may be some light accumulations
of snow across portions of central lower Michigan on the order of an
inch or so in spots. A clipper system will sweep through the Great
Lakes Monday night and potentially bring a couple inches of snow to
central lower Michigan once again. The upcoming work week will
feature warmer temperatures as the pattern shifts a bit.


Short term...(this evening through Monday night)
issued at 330 PM EDT Sat Mar 28 2015

Two main items in the short term are the precipitation event from
midday Sunday into Sunday evening and another Monday night.

Regarding the Sunday afternoon and evening event still have rain and
snow in the forecast especially from Interstate 96 northward. A
strong southerly flow of air will warm readings into the 40s ahead
of the front with the precipitation moving in midday. Dry air in
place in the low levels will wet bulb temperatures down after the
onset of precipitation. We still may be just warm enough though to keep
precipitation mainly rain. Have some very light accumulations in
place across the northern and west portions of the forecast inch or less. Not expecting much impact from any snow that
occurs and ground temperatures have warmed up a bit.

Monday night a clipper will slide through the area. There are some
model indications that a swath of snow will be put down from
northwest to southeast across about the northern half of the
forecast area. Have rain and snow in the forecast once again given
temperatures near critical thresholds. Have some light accums in the
forecast at this point but we will need to keep an eye on this event.

Long term...(tuesday through saturday)
issued at 330 PM EDT Sat Mar 28 2015

There are two main systems to focus on during the long term. The
first is a clipper that will move over lower Michigan Tuesday. The
models are all a bit different in storm track with the clipper. The
NAM is the warmest and farthest north while the European model (ecmwf) is the coldest
and farthest south. We/ll use a blend for precipitation type until the storm
track becomes more firm. It/S possible we could see an inch or two
of light snow along US-10 early Tuesday before temperatures warm and precipitation
mixes with and then changes over to rain. We/ll need to keep an eye
on this system since a continued southern trend in track could mean
more snow and potential travel impacts.

A cold front moving through Thursday could bring some light rain to
the County Warning Area...but the bigger storm may come Friday.

There is still some uncertainty with this phased northern/southern
stream system. The European model (ecmwf) is moving farther south then yesterday. So
the thunderstorm potential looks to be diminishing. The GFS started
south and is now moving north. Either appears as though
we/ll see quite a bit of precipitation. The question is what kind. For now it
appears as though the type will be rain...but that could change.


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 722 PM EDT Sat Mar 28 2015

VFR weather likely through 18z Sunday...however the arrival of
precipitation from the west around that time beginning in kmkg
first will support deteriorating conditions. At this point the
primary precipitation type looks to be rain...however this will
need to be monitored closely as the initially dry airmass could
support snow. I was not confident enough to add it to the tafs at
this time...but it should be monitored closely.

Low level moisture increases through the afternoon and this will
support lowering cloud bases at least down to the MVFR level. A
small risk for IFR exists.

It will be a windy day on Sunday...with gusts over 25 knots likely
and possibly over 30 knots.


issued at 330 PM EDT Sat Mar 28 2015

Rivers remain below bankfull and are holding steady or slowly
falling. Precipitation amounting up to several tenths of an
inch over the next several days is not expected to cause a
significant rise in river levels.


GRR watches/warnings/advisories...


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

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