Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 260558

Area Forecast Discussion
National Weather Service Grand Rapids MI
158 AM EDT Wed Oct 26 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.


Issued at 1100 PM EDT Tue Oct 25 2016

Clouds will continue to lower and thicken tonight. It appears it
will take the bulk of the night if not until daybreak before
precipitation begins to spread in. 1000-850MB layer RH does not
increase significantly until 12z or a little bit after. Expecting
a band of rain to move in near Holland and Muskegon around 12z.
Low temperatures will range from near freezing in the far
northeast to around 40 towards Lake Michigan.


.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 06Z TAFS through 06Z Wednesday night)
Issued at 158 AM EDT Wed Oct 26 2016

Plenty of impacts expected at the terminals in this forecast
period. Some light rain will try to move in across the area from
west to east toward 12z this morning. This should not cause too
much trouble initially as some residual dry air will have to be

The dry air will be overcome this afternoon and much better threat
for rain will come. E/SE winds will pick up and become gusty with
gusts up to 30 knots possible. Cigs and vsbys will drop, and
should become IFR or lower mid-late afternoon. The lower
conditions will last through the end of the forecast period. Winds
will diminish after 00z.


Issued at 315 PM EDT Tue Oct 25 2016

A small craft advisory will go into effect Wednesday morning and
last 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 8 AM this morning to 11 PM EDT this
     evening for LMZ844>849.



SHORT TERM...Laurens
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