Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 250543

Area Forecast Discussion
National Weather Service Grand Rapids MI
143 AM EDT Tue Oct 25 2016


Issued at 330 PM EDT Mon Oct 24 2016

A cold rain will push into the area late Tuesday night and into
Wednesday.  Areas near Highway 10 may even see a mix of rain and
snow, but little to no snow accumulation is expected.  The chilly
rain will continue into Thursday, then briefly end.  More rain is
expected again for Friday and Friday night.

Daytime temperatures will largely reach 50 to 55 with overnight lows
from 35 to 45.


.SHORT TERM...(This evening through Wednesday night)
Issued at 330 PM EDT Mon Oct 24 2016

A soaking chilly rain will push into Southwest Michigan late Tuesday
night and last through Wednesday night.  Some snow mixture is also
expected, inland and toward Highway 10.

Strong fgen is produced ahead of the main system late Tuesday night
when pcpn should form with increasing coverage.  Soundings and
thickness values support a rain/snow mix at the onset for the
interior north, toward RQB and MOP northward.  Some minor
accumulation on grassy areas can not be ruled out both early Wed
morning and again Wed night.  Otherwise the rest of the CWA should
see all rain. The steadiest rains will come Wed afternoon and
evening when the upper and lower jet comes across the area. The
potential to see over an inch of rain, especially for West Central
Lower certainly exists. A raw day for sure with winds gusty toward
25-30 mph.

Until then expect a quiet period tonight into Tuesday evening with
seasonably cool temps

.LONG TERM...(Thursday through Monday)
Issued at 330 PM EDT Mon Oct 24 2016

Main concern is precipitation Friday night. Thermal profiles are too
warm for anything but rain. The GFS and Global GEM are quite similar
in moving a surface low to the north with motion to the east.
ECMWF ensemble members show a split in the track of the low and
associated precipitation. Nonetheless, rain showers look pretty
likely during this time. Otherwise no significant weather expected
with highs generally in the 50s, which is near to slightly below
normal for this time of year.


.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 143 AM EDT Tue Oct 25 2016

Our main focus for the 06z fcsts is on lower cloud cover based
around 3-4k ft coming in today. Right now, it appears that nrn
areas will see some clouds come down early this morning, with
more coming in this afternoon which will get a diurnal boost.
These clouds will then dissipate/move out toward 00z tonight.

Winds will tend to be a bit variable through today, generally
remaining under 6 knots. They will tend a bit more easterly later
in the day and tonight.


Issued at 330 PM EDT Mon Oct 24 2016

Small craft advisory headlines through 8 PM this evening.  We may
need another headline Wed afternoon and night with a strong SE flow.


Issued at 330 PM EDT Mon Oct 24 2016

The upper half of the Grand River basin (Ionia and upstream
tributaries) is largely running above climatological normal for
streamflow in mid October. The upcoming Wed to Thu system is
expected to produce at least a half inch of precipitation across the
whole area, with some of the area possibly eclipsing an inch. While
not the most likely scenario at this time, ensemble river models
suggest hypothetical 1.25 inch totals across the upper half of the
Grand River basin would lead to above-bankfull rises at some of the
typically flood-prone river forecast points.




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