Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 280210

Area Forecast Discussion
National Weather Service Grand Rapids MI
1010 PM EDT MON JUN 27 2016


Issued at 329 PM EDT Mon Jun 27 2016

A cold front will be pushing in from the northwest tonight. This
will result in increasing cloud cover this evening and possibly a
few showers tonight. Much cooler air will settle into Lower
Michigan behind the front on Tuesday. A few showers may linger,
but limited moisture should keep most locations dry. Aside from a
quick shot of rain late Thursday into Friday, much of the week is
dry with temperatures near or slightly below normal.


Issued at 1010 PM EDT Mon Jun 27 2016

Have delayed the increase in cloud cover a bit for areas south of
a line from Muskegon to Mt Pleasant based on latest satellite
imagery and latest model RH Trends. Probability of any measurable
precip tonight looks really low and generally restricted to areas
north of a Muskegon to Mt Pleasant line including Ludington.
Probably just sprinkles if anything occurs.


.SHORT TERM...(This evening through Wednesday night)
Issued at 329 PM EDT Mon Jun 27 2016

Visible satellite imagery continues to show the gradual southward
progression of the cloud shield over Northern and Central Lower
Michigan. This trend will continue with much of Southwest Lower
Michigan seeing more in the way of low to mid level clouds through
the afternoon and evening hours.

Moisture remains limited and largely confined to the lower levels
with this front. A few showers may pop overnight along the front
as it pushes from northwest to southeast. Some showers may linger
into Tuesday, but are expected to be quick-hitters with only light
precipitation. The bigger story is the cooler air that filters in
through the day Tuesday. High temperatures will range from the
upper 60s to lower 70s, which is not too entirely far off from
record min-max benchmarks.

High pressure will result in more dry weather from late Tuesday
through Wednesday. Temperatures will moderate back to near normal
values with highs in the mid-upper 70s Wednesday.

.LONG TERM...(Thursday through Monday)
Issued at 329 PM EDT Mon Jun 27 2016

Main focus of the long term is on the Thursday through Friday time
frame as a cold front will be traversing the Great Lakes region.
Outside of this time frame, the remainder of the long term looks
dry. The GFS and ECMWF are consistent in showing a frontal passage
occurring on Thursday night and feel this will be our best chance at
precipitation in the long term. Even Thursday and Friday look
relatively dry as the front will be off to our north on Thursday and
likely to our south on Friday. Precipitation amounts look fairly
paltry, on the order of a tenth or two of an inch. There is some
instability in the models but it is somewhat minimal, with CAPE values
on the order of 500 J/KG or less via the ECMWF.

Overall the pattern in the long term will feature cooler than normal
temperatures for this time of year and dry weather. Highs
will generally be in the upper 70s to around 80, while normal highs
are typically in the lower 80s.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 759 PM EDT Mon Jun 27 2016

The leading edge of the cloud shield dropping down from the north
has bases above 4000 ft, so believe the bulk of the night will be
VFR across srn lwr MI.

A period of MVFR cigs and perhaps a few light showers or
sprinkles should occur between roughly 12z and 16z Tuesday, with
highest probability of MVFR cigs at GRR and LAN. Confidence for
MVFR cigs is a bit lower at the other terminals based on low level
RH progs, but did include a brief mention of 2500 ft cigs at most
of the terminals on Tuesday morning.

Otherwise VFR is likely after 18z Tuesday with SCT-BKN clouds
around 4000 ft and north winds 10-15 kts.


Issued at 329 PM EDT Mon Jun 27 2016

A cold front will result in winds shifting from west to north and
increasing tonight through Tuesday. Northerly flow is expected to
result in high wave action, especially for open waters and coastal
areas over the southern half of Lake Michigan. Dangerous swimming
conditions will become common all along the lakeshore as we go
through the day Tuesday. Waves of 3 to 6 feet will also make for
hazardous boating conditions. As a result, a small craft advisory
will extend southward Tuesday, along with the beach hazard

Winds and waves will begin to subside late Tuesday into Wednesday,
which may allow us to assess dropping the headlines at that time.


Issued at 223 PM EDT Mon Jun 27 2016

Slight uptick in river levels near Scottville and Whitehall from
Sunday`s 0.75 to 1.5 inches of rain, and they are far from any
flood threat. The next best chance of rain will be late Thursday
into Friday. Amounts do not look substantial enough to even put a
dent in the recent dry weather.


.GRR Watches/Warnings/Advisories...
MI...Beach Hazards Statement from 6 AM EDT Tuesday through late
     Tuesday night for MIZ037-043-050-056-064-071.

LM...Small Craft Advisory until 8 PM EDT Tuesday for LMZ848-849.

     Small Craft Advisory from 2 AM Tuesday to 2 AM EDT Wednesday for



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