Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 220730

Area Forecast Discussion
National Weather Service Grand Rapids MI
330 AM EDT Sat Oct 22 2016

Synopsis/Short Term/Long Term/Marine

Issued at 330 AM EDT Sat Oct 22 2016

Temperatures will average close to normal over the next week or so.
Relatively quiet weather is expected until mid week when a low
pressure system brings another shot of widespread rain.

In the short term, high pressure will briefly impact the Michigan
today then another cold front will move south through the Great
Lakes on Sunday. Only a few light showers or sprinkles are expected
with the cold front then high pressure will move back in on Monday.


.SHORT TERM...(Today through Monday)
Issued at 330 AM EDT Sat Oct 22 2016

The fcst challenge today is cloud cover. While much of the area is
clear early this morning, the backing low level flow should send
lake effect cloudiness inland this morning. Also, there is a band of
warm advection mid level clouds currently marching east across
Wisconsin that will drift through this afternoon. These two areas of
clouds will lead to some cloudy periods today, but still some peeks
of sunshine expected from time to time. Some sprinkles cannot be
ruled out when the lake clouds come back onshore this morning.

Models have trended faster and farther south with the weak sfc low
moving east through Michigan on Sunday, with the cold front progged
to be through most of the area already by 00Z Monday. The strong
warm advection which comes in later tonight into Sunday morning
ahead of the low essentially gets pinched off and shunted south
quicker, so guidance highs have trended down a few degrees. Some low
clouds and and sprinkles will probably move south behind the front
Sunday afternoon/night, with a few hundredths of measurable precip
possible north and east of GRR.

There will likely be some lingering post frontal stratus on Monday
morning, which could linger in the afternoon under strengthening
subsidence inversion aloft. We are getting into the time of year
when stratus is really tough to get rid of.

.LONG TERM...(Monday night through Friday)
Issued at 330 AM EDT Sat Oct 22 2016

Forecast concerns deal with rain chances mid week. Overall, the
ecmwf and gfs are in worse agreement mid week than they were last
night, but in fairly good agreement up until Tuesday.

High pressure over the western Great Lakes Monday night will drift
east by Tuesday night. A cool but dry day will see increasing clouds
late Tuesday as low pressure develops in the plains. A fairly deep
upper low will support the development of the sfc low as it moves
northeast toward Lower Michigan. That`s where the models diverge.
The ecmwf continues to show the low moving across Michigan Wednesday
and Thursday but the gfs now turns the low south and fills it. This
is due to the gfs cutting off the upper low and the ecmwf remaining
more progressive. Seems like the gfs solution is a radical departure
from previous runs and we/ll lean toward the ecmwf for now. That
means a chilly rainy day likely Wednesday as the low moves across
the cwa. We`ll continue with the high pops. Temps will likely remain
in the 40s over the northern cwa and only around 50 elsewhere.

Conditions will improve slowly as the low moves east into Canada
Thursday. Pcpn will diminish and temps will climb toward 60 by


.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 145 AM EDT Sat Oct 22 2016

Latest satellite imagery shows clouds continuing to scatter out
across the cwa. We`ll likely see some cu form during the day, but
vfr conditions are expected. As high pressure moves east, north
winds will shift to the west.


Issued at 330 AM EDT Sat Oct 22 2016

Still some 5 footers at St Joseph at 3 am but the trend will be
downward this morning and will let the Small Craft advisory over the
srn zones expire. We may need advisories again Sunday afternoon and
night for the north flow behind the next cold front.


Issued at 1133 AM EDT Fri Oct 21 2016

Recent rainfall did over perform near Jackson on Thursday.
However, it was not by much and hydro response were fairly brief.
All sites remained well within banks and most locations affected
by rainfall are now stabilizing or falling.

The next 5 days includes very little precipitation. It is not
until the middle of next week that Lower Michigan gets into a
wetter pattern. The current forecast plots the heaviest rain well
west of Lake Michigan, which will continue to be reassessed for
any potential changes in coming days.

There are no flooding concerns at this time.


MI...Frost Advisory until 9 AM EDT this morning for MIZ037-043-050-

     Frost Advisory until 10 AM EDT this morning for MIZ038>040-

LM...Small Craft Advisory until 4 AM EDT early this morning for



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