Scientific Forecaster Discussion

Return to Local Conditions & Forecast
Area forecast discussion 
National Weather Service Grand Rapids Michigan
653 PM EDT Friday Apr 18 2014

Latest update...

issued at 330 PM EDT Friday Apr 18 2014

A pleasant weekend is in store with high temperatures around 60
Saturday and near 70 on Easter Sunday. A weak frontal boundary may
produce a few light rain showers north of Grand Rapids on Saturday
night and Sunday otherwise expect plenty of sunshine over the

Monday will be rather mild as well... with a chance of showers
areawide. However cooler temperatures in the 50s will follow for
Tuesday and Wednesday behind a cold front which passes through on
Monday night.


Short term...(this evening through Sunday night)
issued at 330 PM EDT Friday Apr 18 2014

Not much going on in the short term. Combination of clear skies
and dry air mass associated with a surface ridge will result in large
diurnal temperature swings of 30 degrees or more over the weekend.

Typically in this regime we see can see lows 5 degrees below MOS
guidance and highs 5 degrees warmer than MOS. This may drive
afternoon relative humidity values down below 30 percent Saturday and Sunday
afternoons... possibly creating a slightly elevated fire risk.

For the most part the clouds and rain showers associated with the
frontal boundary will be to our north and west over the weekend.
This is good news as some flooding still continues along the
Muskegon river. If showers do occur along the U.S. 10 corridor...
amounts should be mostly under one quarter inch.

Long term...(monday through friday)
issued at 330 PM EDT Friday Apr 18 2014

We continue to to watch two different systems in the long term. The
first system is at the beginning of the long term...while the other
is at the end of the period. We have not really made any changes to
the first system. We are now siding with the cooler solution for the
system at the end of the we have trended temperatures down a
bit for late next week.

It still looks like we could see some dry and warm weather early on
Monday...especially the further southeast you go. A stationary front will
start out the day mainly north of the area. A cold front will move
in from the west later in the day as a southern stream wave and northern
stream wave both move into the area. It will be at this time that
rain chances will increase everywhere. This will last into early Tuesday
until the upper trough passes through the area. Colder air will then
filter into the area.

We will see a dry and cool period then for later Tuesday through Wednesday
night. We will see an upper ridge slowly build toward the area. High
pressure centered north of our area will usher in cool air with the
nearly flow ahead of the surface ridge. This air will not be nearly as
cold as this past high should end up well into the 50s.

Yesterday it appeared that we may be headed for another major warm
up for the end of next week. The confidence in the warm up has been
reduced we now believe it will be cooler and more
wet. We are following the model and ensemble consensus minus the GFS
suite where the upper low will be weaker and the warm air will not
make it as far north as previously expected.

It seems that the GFS is an outlier with the warmer solution with a
stronger upper low. The GFS appears to be exhibiting its common bias
of having too strong of an upper low due to abnormally strong short
waves likely due to convection. The other models and Euro ensemble
favor a weaker low and further south...which would end up cooler. We
have not entirely bought into this yet...but have trended the forecast
cooler and wetter.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 653 PM EDT Friday Apr 18 2014

VFR conditions will prevail across the area through Saturday.
Winds will become light out of the northeast after dark then
slowly turn to the east and increase to 10 to 15 knots by Saturday
afternoon. Skies should be clear or nearly clear through Saturday


Fire weather...
issued at 330 PM EDT Friday Apr 18 2014

An elevated fire danger may develop this weekend as afternoon
relative humidities fall to 30 percent or less with winds
around 10-15 miles per hour. Fires could spread easily since green up has not
yet occurred and the fine fuels on the ground are dry even though
soils are moist from recent rains.


issued at 125 PM EDT Friday Apr 18 2014

River flooding has by no means ended across the Muskegon river.
Moderate to major flooding continues...with Evart finally falling
below major flood stage by late tonight / early Saturday. The
Croton dam continues to steadily release less flow downstream...and
should fall below moderate flood by Saturday morning. High water
will continue to impact travel around the river through the
weekend and will still be affecting many properties that have
already flooded. No rises are foreseen on the Muskegon river
through the weekend.

Areal flooding continues throughout Newaygo County...which has not
recovered from high water impacts to the Road systems. As
such...the areal Flood Warning continues for the County for some
water covered roads that are impeding travel.

Elsewhere...river flooding has subsided considerably on the pere
Marquette...white...and Chippewa rivers. The Grand River is
running higher than normal at this time but no serious impacts to
homes or properties are occurring.


GRR watches/warnings/advisories...


short term...Meade
long term...njj
fire weather...Meade