Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 211533

Area Forecast Discussion
National Weather Service Grand Rapids MI
1133 AM EDT Fri Oct 21 2016


Issued at 330 AM EDT Fri Oct 21 2016

Temperatures closer to normal for this time of year can be expected
today and Saturday, then a slight warmup will occur on Sunday. That
warm up will be very short lived however and most of next week will
have near normal highs in the low to mid 50s.


Issued at 1053 AM EDT Fri Oct 21 2016

Will issue a frost advisory for most of the CWA for tonight.

We continue to advect in drier air and with dew points in the mid
and upper 30s already, frost appears likely late tonight. The low
clouds may be a factor, but feel we will see occasional pockets of
mostly clear skies inland from the lake, that most areas will dip
into the low and mid 30s for a period tonight. The lake shore will
continue to see more clouds due to the lake effect, but will also
put these counties into the advisory, minus Van Buren County,
since eastern areas of these counties should see some clearing and
at least patchy frost.

We are nearing the end of the growing season, but there are still
concerns for the grape crop that has largely not been harvested
yet. Also due to wet fields some crops that normal would have been
harvested by now are still in the fields. Backyard potted plants
will also need to be brought in.


.SHORT TERM...(Today through Sunday)
Issued at 330 AM EDT Fri Oct 21 2016

Banded precip has been slow to end around Jackson so will carry a
few more hours of scattered rain showers in the far southeast CWFA
this morning. Otherwise considerable cumulus/stratocu clouds should
linger today with upr trough/cold pool aloft. Dry northerly flow may
counter this a bit so will side with a partly sunny sky fcst today
for most zones.

Almost due north flow will result in most of the lake effect showers
remaining offshore this morning with the exception of the wrn
portion of Mason and Oceana counties where likely pops may even be
in order. The flow does back slightly this afternoon and some of
those showers may begin impacting more of the lakeshore,
particularly south of Holland.

Some lake effect will probably linger tonight as well near the coast,
although if enough clearing takes place inland, then a land breeze
will push them offshore overnight. Clearing inland was also dictate
temps and degree of frost formation. Since questions still remain on
extent of clearing and if the winds will drop off, for now will go
with mid to upr 30s inland tonight and patchy frost.

Some concern on Saturday that lake clouds will spread inland in
backing westerly flow and limit amount of sunshine. Prospects for
sun are better on Sunday due as warm advection erodes lake clouds,
but northern areas should see an increase in clouds late as front
slips south from nrn lwr MI.

.LONG TERM...(Sunday night through Thursday)
Issued at 330 AM EDT Fri Oct 21 2016

The active weather is back-loaded during the long term...mainly
Wednesday into Thursday.

High pressure will move from the Northern Plains sunday night east
to New England by Tuesday. That will produce a few days of dry
weather though mid week. Developing low pressure in the Plains will
make a run at the Great Lakes Wednesday into Thursday. Both the
ecmwf and gfs take the sfc low across Lower Michigan Wednesday
night. A large area of rain is progd with this system, which also
has good upper support. A short wave is progd to move across the
state late Wednesday. Light rain will linger into Thursday as the
low moves east.

Highs through the period will be close to normal...mid 50s with lows
in the 30s and 40s.


.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 740 AM EDT Fri Oct 21 2016

VFR cigs around 3500 ft AGL are expected today, with a few showers
possible at MKG this afternoon and evening. Some clearing is
likely tonight, mainly east of GRR and AZO. Northerly sfc winds
will average around 10 kts today, diminishing slightly tonight.


Issued at 1053 AM EDT Fri Oct 21 2016

Conditions were gradually improving over the lake shore waters
this morning and this trend will continue as winds slowly
diminish. Will adjust the small craft advisory to end at 1 PM
north of Holland. Areas south of Holland will be last to subside
with the northerly flow, and an overnight ending still looks good.


Issued at 1133 AM EDT Fri Oct 21 2016

Recent rainfall did overperform near Jackson on Thursday.
However, it was not by much and hydro response were fairly brief.
All sites remained well within banks and most locations affected
by rainfall are now stabilizing or falling.

The next 5 days includes very little precipitation. It is not
until the middle of next week that Lower Michigan gets into a
wetter pattern. The current forecast plots the heaviest rain well
west of Lake Michigan, which will continue to be reassessed for
any potential changes in coming days.

There are no flooding concerns at this time.


MI...Frost Advisory from 2 AM to 9 AM EDT Saturday for MIZ037-043-050-

     Frost Advisory from 11 PM this evening to 10 AM EDT Saturday for

LM...Small Craft Advisory until 1 PM EDT this afternoon for

     Small Craft Advisory until 4 AM EDT Saturday for LMZ844-845.



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