Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 270551

Area Forecast Discussion
National Weather Service Grand Rapids MI
151 AM EDT Thu Oct 27 2016


Issued at 320 PM EDT Wed Oct 26 2016

A low pressure system moving east across the Great Lakes region
will continue to bring rain through this evening and mixed rain
and snow north of interstate 96. Light precipitation will linger into
Thursday morning before fair weather returns late Thursday through
Friday. The next system will bring a few showers Friday night and


Issued at 1023 PM EDT Wed Oct 26 2016

Earlier many of the Metar obs north of I-96 were reporting snow
for precip type, and social media reports indicated some light
snow accumulations as much as 1-2 inches on the grass, cars,
elevated sfcs, etc. However now most of the Metars are showing
rain as the dominate precip type.

While some wet snow or rain/snow mix may still impact areas north
of a line from Baldwin to Mt Pleasant through 09z, additional
snow accumulations are expected to be generally less than an

Precipitation intensities should gradually decrease with the
arrival of the mid level dry slot later tonight as upr low moves
across nrn lwr MI. Arrival of the dry slot should also decrease
any snow potential, even in colder sfc temp region north of I-96,
as shallower moisture profiles lead to no ice nucleation aloft in
the clouds.

Outside of the mixed precip challenges of the evening, look for
the rain near and south of I-96 to gradually taper off to ocnl
drizzle overnight as the dry slot arrives.


.SHORT TERM...(This evening through Friday)
Issued at 320 PM EDT Wed Oct 26 2016

A polling of 12Z model fcst soundings and analysis of wbz heights
and model trends information suggests that pcpn will continue to
mix with/change over to wet light snow at times late this
afternoon through tonight north of I-96.

The greatest potential for light snow accumulations of an inch or two
mainly on grassy surfaces will be near to north of a line from Big
Rapids to Mt. Pleasant. Slightly lower snow accumulations of around a
half an inch on grassy surfaces are anticipated north of I-96 and
south of a line from Pentwater to Big Rapids and Mt. Pleasant.

For areas near to south of I-96 plain rain will continue late
this afternoon and evening before gradually tapering off late
tonight into Thursday morning as the low pressure system continues
to move east to just east of Detroit by 12Z Thursday.

Fair weather will then return Thursday afternoon through Friday as
a high pressure ridge builds in. Temperatures will remain
seasonably cool through Thursday before moderating significantly
beginning Friday as as winds become southerly on the back side of
the departing ridge.

.LONG TERM...(Friday night through Wednesday)
Issued at 320 PM EDT Wed Oct 26 2016

We continue to see a trend towards drier weather in the forecast
through Saturday. There might be a better chance for rain Saturday
night however.

It looks increasingly likely that Friday night will be dry as
significantly more ECMWF ensemble members keep precipitation north
of the area.

Ensembles, particularly the GEFS, better favor rain chances Saturday
night into early Sunday morning with better chances farther south
near I-94. I could see rain chances in this time frame gradually
increasing as we get closer to the event.

GFS deterministic and several GEFS members suggest another shot of
rain Monday night with a pronounced upper trough, but the GFS family
differs significantly from the ECMWF and CMC solutions that feature
substantial upper ridging with rain staying well north into Canada,
so not a lot of confidence in rain here at this point.

Otherwise, a good chance for warm temperatures next week with highs
Tuesday making a run at 70 degrees to the south. This would be about
15 degrees above normal.


.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 151 AM EDT Thu Oct 27 2016

Conditions continue to deteriorate early this morning, although we
are approaching the worst conditions expected. Rain will be coming
to an end over the next few hours from W to E. However, the LIFR
cigs can be expected to stick around through sunrise. They will
slowly lift/improve through the daytime hours, and go VFR toward
the end of the forecast period.

Winds will not produce nearly the amount of impact as on
Wednesday. Wind speeds should remain below 12 knots.


Issued at 1023 PM EDT Wed Oct 26 2016

Have extended the small craft advisory through 4 am north of
Holland where wind speeds stay up longer than south of Holland.
Kept the 11 pm expiration for Holland south. Wave heights at the
coast are not at SCA criteria due to offshore flow, but wind
speeds 20-25 kts warrant the headline until they diminish.


Issued at 1254 PM EDT Wed Oct 26 2016

Widespread rainfall will continue over the area through tonight.
Between 0.50-1.00 inches of total rainfall is expected. Most rivers
and streams will stay below bankfull. River advisories are out
for Sycamore Creek at Holt and Maple River at Maple Rapids.
Flooding is not expected.


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



SHORT TERM...Laurens
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