Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 240720

Area Forecast Discussion
National Weather Service Grand Rapids MI
320 AM EDT Mon Oct 24 2016

Synopsis/Short Term/Long Term/Marine

Issued at 320 EDT Mon Oct 24 2016

High pressure building into Lower Michigan should bring fair and
cool weather today and Tuesday. Low pressure moving in from the
west on Wednesday will bring wet weather Wednesday and Wednesday


.SHORT TERM...(Today through Wednesday)
Issued at 320 EDT Mon Oct 24 2016

Primary forecast issue is for p-type Wednesday across the northern
zones as thermal profiles show possibility of frozen precip
reaching the ground.

Low pressure center tracking across the central Plains will bring
an area of overrunning precip into Lower Michigan Wednesday
morning with cold sfc high centered south of James Bay providing
an easterly flow of cold dry air. Model soundings show wet bulb
zero less than 1000 feet AGL much of Wednesday. Some frozen precip
is possible, especially across the high ground of Osceola County,
but even there, skin temps will probably be too warm for any
accums. This is something we will have to watch, though.

For today...Will keep slight chance POPs going this morning
across the far northern zones per current radar trends which show
lake enhanced rain showers across the U.P. and northern Lower
Michigan. Sfc ridging and some subsidence should bring an end to
the showers by afternoon. Tonight and Tuesday night look frosty
but the growing season is over, so no frost/freeze headlines will
be issued.

.LONG TERM...(Wednesday night through Sunday)
Issued at 320 EDT Mon Oct 24 2016

Forecast concerns deal with he movement of low pressure across
the cwa Wednesday night/Thursday and the potential for more pcpn
over the weekend.

For several days, the models have been advertising a strengthening
low pressure system moving from the Plains across the southern Great
Lakes midweek. The 00z version of the ecmwf and gfs are in pretty
good agreement showing the low crossing southern Lower
Michigan/Northern Indiana Wednesday night and moving out of the
state Thursday. We`re likely to see a fairly steady and cold rain
Wednesday night and we have high pops to cover that. Thermal
profiles suggest that we may see some wet snow mix in with the rain
over the far northern cwa Wednesday night and we added this to the
grids. Don`t think we`ll see any accumulation at this point as the
ground is still fairly warm, but sfc temps are expected to fall to
near freezing Wednesday night.

The weekend system looks like a clipper type system that will
generate some light rain Friday night and end Saturday morning.
Another shot of cooler air will follow the clipper and highs Sunday
will likely top out around 50...several degrees below normal.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1253 AM EDT Mon Oct 24 2016

Sct-bkn vfr stratocu is expected to move south across the taf
sites this morning. Look for clouds to scatter out this afternoon.


Issued at 320 EDT Mon Oct 24 2016

Winds and waves will slowly decrease today and should drop below
Small Craft Advisory criteria this afternoon.


Issued at 330 PM EDT Sun Oct 23 2016

No significant hydro impacts are expected over the next week.
Widespread rain is expected Wednesday into Thursday. Rainfall totals
between 0.50-1.00 inch are expected, which will result in river
rises late in the week into next weekend. Mostly within bank rises
are expected.


LM...Small Craft Advisory until 2 PM EDT this afternoon for



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