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Area forecast discussion 
National Weather Service Grand Rapids Michigan
729 am EDT Friday Oct 9 2015

Latest update...

issued at 330 am EDT Friday Oct 9 2015

A cold front will slide south of the state of Michigan this morning
with all of the rain associated with ending overnight. Today we will
see considerable clouds this morning in the wake of the front...with
skies turning partly to mostly sunny this afternoon. A cooler and
drier air mass will work into the area today with high temperatures
feeling more fall like. Highs today will only top out in the upper
50s to lower 60s. A cool and potentially frosty night is expected
tonight with mainly clear skies and patchy frost possible. Lows
across central lower Michigan will likely dip into the upper 30s.
Dry weather is forecast for the weekend with a warming trend into
Sunday and Monday. Highs Saturday will be in the lower 60s but warm
to around 70 for Sunday.


Short term...(today through sunday)
issued at 330 am EDT Friday Oct 9 2015

Limited forecast concerns in the short term with dry weather
forecast throughout.

Skies will begin the day mostly cloudy but decreasing clouds should
be noted this afternoon. Beyond today...mostly clear to partly
cloudy skies are anticipated for the tonight through Sunday portion
of the forecast. There is the potential for some lake stratocumulus
off of Northern Lake Michigan late tonight into Saturday
morning...with Ludington potentially impacted by these clouds.
Overall though...dry and quiet weather.

The only item of note is the potential for some frost tonight. At
this point thinking we could see patchy frost over almost the entire
area...with the best potential across interior central lower
Michigan. Confined the mention in the forecast to up there at this
point. No headlines yet given forecast low temperatures in the upper 30s.

Long term...(sunday night through thursday)
issued at 330 am EDT Friday Oct 9 2015

The main concern during the long term will be the passage of a cold
front through the County Warning Area Monday. The models seem to have a good handle
on this front and are similar in position and timing through the County Warning Area
Monday afternoon leading to high confidence. The low associated with
the front is well north into Ontario and so we won't see much if any
precipitation from it. Both the European model (ecmwf) and GFS show a deep short wave pushing
the front through the Great Lakes. This may be enough to help
overcome the lack of moisture with the system and produce a few
showers. We have low chance probability of precipitation in the grids Monday but are dry Monday
night. Quantitative precipitation forecast is less than a tenth of an inch with this system.

High pressure at the surface and aloft will quickly build into the Great
Lakes behind the front and more dry weather is expected. Temperatures through
the period will be a few degrees above normal with the highest temperatures
Monday afternoon ahead of the front around 70.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 728 am EDT Friday Oct 9 2015

Fairly widespread MVFR ceilings are in place across southwest
lower Michigan...extending northward into the northern Great
Lakes as well. A northerly flow is in place ceilings
will likely remain MVFR into the midday hours as the clouds move
southward. There are a few pockets of VFR mixed in as well. Spotty
IFR remains just behind the cold front that is slipping south of
the kjxn may see some ceiling just under 1000ft through

The bottom line is quite a bit of MVFR this morning...lifting to
VFR this afternoon and scattering out this afternoon and evening
from north to south. Tonight is expected to be mostly clear. Winds
will be northerly at 10 to 20 knots today becoming nearly calm
tonight under high pressure.


issued at 330 am EDT Friday Oct 9 2015

Winds are just beginning to kick up in northerly flow behind the
cold front which has now swept across all of Lake Michigan. Winds at
the Middle Lake buoys are both gusting to around 25 knots...with a few
gusts on the Door Peninsula in Wisconsin approaching 30 knots. Waves
will correspondingly build this morning...with solid 4 to 7 footers
expected along the entire shoreline. The peak in the wave field will
likely be before noon across Southern Lake Michigan where we may see
a few buoys near 8 feet. Winds and waves will subside from north to
south late this afternoon and especially from sunset through
midnight or so. Late tonight through Saturday morning will feature
quiescent conditions before waves build once again in southwest flow
Saturday evening into Saturday night. Current Small Craft Advisory
looks good from now into tonight and we may need another for the
southwest flow Saturday night.


issued at 1124 am EDT Thursday Oct 8 2015

No flooding concerns to mention over the next several days.

A frontal boundary will bring rainfall (possibly a thunderstorm)
to the area later today and into tonight. Total rainfall amounts
through Friday morning will be enough to wet the soil. Rainfall
is expected to be nothing more than beneficial to what is generally
dry ground.

A dry period is expected over the weekend before another quick hit
of showers is possible early next week.


GRR watches/warnings/advisories...
Lm...Small Craft Advisory until 2 am EDT Saturday for lmz844>849.



short term...Duke
long term...99

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