Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 252355

Area Forecast Discussion
National Weather Service Grand Rapids MI
755 PM EDT Tue Oct 25 2016


Issued at 315 PM EDT Tue Oct 25 2016

Fair weather will continue through this evening. A low pressure
system will bring rain Wednesday through Wednesday night. Some wet
snow may mix in with rain at times late Wednesday afternoon
through Wednesday night north of a line from Big Rapids to Mount
Pleasant. Temperatures will remain seasonably cool through
Thursday before undergoing a significant moderating trend Friday
through Saturday.


.SHORT TERM...(This evening through Thursday night)
Issued at 315 PM EDT Tue Oct 25 2016

The primary short term fcst challenge is to determine potential
for wet snow flakes to mix in with rain north of a line from KRQB
to KMOP late Wednesday through Wednesday night. 12Z Mav/met
numerical guidance suggests pcpn will fall in all liquid form even
across our far northern fcst area.

However a polling of model fcst soundings shows potential for a
period of wet snow or mixed rain/wet snow mainly across our far
nne fcst area. Only light snow accumulations of an inch or less
are anticipated mostly on grassy surfaces and relatively higher
elevations of our extreme nne fcst area.

This system will only bring rain to the vast majority of our fcst
area Wednesday through Wednesday night. High temperatures tomorrow
will only reach the lower to middle 40s due to the combination of
extensive low clouds and rain and increasing easterly winds.

Some very light pcpn may linger into early Thursday before pcpn
comes to an end. For this evening, fair weather will continue with
rain not arriving into our sw fcst area until early Wednesday

.LONG TERM...(Friday through Tuesday)
Issued at 315 PM EDT Tue Oct 25 2016

Rain chances are still in order Friday night, but there is a bit
less certainty than before. 25/00Z deterministic ECMWF was fairly
wet during this time, but a sizable majority of the ensemble members
were not. Deterministic GFS and CMC, as well as the GEFS, all
support a drier outcome overall. Good consensus on better overall
chances to the north, and have this advertised in the forecast.

We are forecasting drier conditions than before for the weekend,
with really only a slight chance for rain Saturday night. Overall
forecast certainty is much lower here due to the high potential for
timing and amplitude variations with waves in the fast flow pattern

Featured slight chance PoPs early next week, but this is highly
uncertain and therefore quite subject to change.


.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 754 PM EDT Tue Oct 25 2016

A gradual deterioration of aviation conditions is expected the
next 24 hours. VFR weather will prevail tonight with cloud bases
lowering from 20000ft to 10000ft overnight and to 4000ft around
sunrise. On Wednesday, ceilings will lower further dropping from
4000ft towards 1000ft or potentially even into the IFR category
below 1000ft after 18z.

A low pressure system moving through the lower Great Lakes region
will spread rain and lowering ceilings into the area on Wednesday.
Visibilities will lower to at least MVFR from midday through the
afternoon hours of Wednesday. The rain should be moving ashore off
of Lake Michigan around 800am or 900am Wednesday morning.

Winds will be easterly at 10 knots or less tonight but increase
into the 10-20 knot range with some higher gusts on Wednesday.


Issued at 315 PM EDT Tue Oct 25 2016

A small craft advisory will go into effect from late Wednesday
morning through Wednesday evening as easterly winds will ramp up
to 15 to 25 kts with gusts to 30 kts. Wave heights mainly from 2
to 4 feet are expected Wednesday with higher waves further
offshore given the easterly winds.


Issued at 315 PM EDT Tue Oct 25 2016

Widespread rainfall is expected over the whole area Wednesday
through Wednesday night. Between 0.50-1.00 inches of rain is
expected. Most rivers and streams will stay below bankfull. There is
a low chance for a couple of the typically flood-prone river
forecast points, such as Sycamore Creek at Holt, to exceed bankfull.
Significant flooding is not expected. Sycamore Creek at Holt could
approach bankfull stage (6 ft) as early as Wednesday evening.


LM...Small Craft Advisory from 10 AM to 11 PM EDT Wednesday for



SHORT TERM...Laurens
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