Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 241930

Area Forecast Discussion
National Weather Service Grand Rapids MI
330 PM EDT Mon Oct 24 2016

Synopsis/Short Term/Long Term/Hydro/Marine

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 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.

Storng fgen is produced ahead of the main system late Tuesday night
when pcpn should form with increasing coverage.  Soundings and
thickiness 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
earlyWedmorning 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 low jet comes across the area. The
potentail to see over an inch of rain, especailly 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 18Z TAFS through 18Z Tuesday afternoon)
Issued at 155 PM EDT Mon Oct 24 2016

High confidence for VFR conditions at all terminals through 12Z
Tuesday. There have been sprinkles reported at HTL and MBS, but
expect this to remain north and east of the terminals this
afternoon. VFR cigs will gradually erode this afternoon, leaving
scattered and possibly broken layers above 10000 ft AGL overnight.


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 storng 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.


LM...Small Craft Advisory until 8 PM EDT this evening for LMZ844>849.



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