Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 250926

Area Forecast Discussion
National Weather Service Grand Rapids MI
526 AM EDT MON JUL 25 2016


Issued at 214 AM EDT Mon Jul 25 2016

A high pressure system centered in Iowa will build slowly east
today and into Michigan on Tuesday. This fair weather system will
act to dry out the region and lower temperatures closer to
seasonable values. A low pressure system will approach the Great
Lakes region Wednesday into Thursday bringing with it an increased
potential for showers.


Issued at 523 AM EDT Mon Jul 25 2016

The South Haven buoy was up close to 5 feet as of 5 am. Thus a
headline was needed for parts of the nearshore waters. The update
has been sent.


.SHORT TERM...(Today through Wednesday)
Issued at 214 AM EDT Mon Jul 25 2016

The main challenge deals with the precipitation chances this
morning. I did raise pops for southeast parts of the CWA to start
the morning.

There have been a few stronger thunderstorms in southern Jackson
county early this morning. The axis of stronger instability
associated with these storms will pivot east over the next couple
of hours. Thus the risk for thunderstorms will decrease through
daybreak. However...the mid level wave is still hanging back. The
radar does show returns over Lake an area where the DGZ is
forecasted to be moist. Bufkit profiles show a dry layer below the
moist it is not certain that what is over the lake is
reaching the ground. My though is that with a still very moist low
level airmass over southeast parts of the cwa...that I should
increase pops for a few hours to start the day until the mid level
wave tracks though.

With skies clearing out and diminishing winds tonight...there
should be some patchy fog developing especially up over northern
parts of the CWA.  A similar setup for Tuesday night as well.

I do see a small risk for a thunderstorm arriving...mainly Tuesday
night for northwest parts of the CWA. This would include
Ludington. Mid level cooling develops while warm and moist air
advection develops in the low levels. This will act to destabilize
the atmosphere somewhat...possibly leading to a storm or two. A
better chance for thunderstorms is on Wednesday. The mid level
cooling continues. Thus we may see a couple of storms developing.

.LONG TERM...(Wednesday night through Sunday)
Issued at 214 AM EDT Mon Jul 25 2016

The extended portion of the forecast features a return to more
seasonable temperatures and multiple chances for showers and
thunderstorms. A series of a couple shortwaves will dig out an upper
level trough over the Midwest and Great Lakes Thursday into Friday.
During this time, an upper level ridge that was previously over the
southern CONUS will amplify over the western coast of North America.

In general, expect a fair amount of cloudiness late in the work week
into the early part of the weekend. Showers are expected at times,
but models are not consistent on the handling of any single,
significant low-level feature. After highs in the low to mid 80s
Thursday, temps will hold in the lower 80s Friday through the
weekend. Lows will be in the upper 50s and 60s.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 204 AM EDT Mon Jul 25 2016

Rain and isolated thunderstorms are currently pushing across
Southern Lower Michigan and will likely impact AZO, BTL, and JXN
over the next couple of hours. This precipitation is associated
with a surface cold front currently pushing through Michigan.
Mainly dry weather is expected after 09z.

MVFR visibility restrictions are possible early this morning due
to fog. Winds will gradually veer northwesterly through 12z.


Issued at 214 AM EDT Mon Jul 25 2016

The wind and waves will continue to diminish today and Tuesday as
the pressure gradient weakens. Waves will initially start out
today in the 2 to 3 foot range.


Issued at 1250 PM EDT Sun Jul 24 2016

No river flooding is expected through next week. Area wide rain of
around an inch with locally up to 3 inches (mainly near Lake
Michigan) has fallen since Saturday evening. Another wave of showers
and storms are possible tonight. A small chance of rain is also in
the forecast Wednesday through Friday. River levels are at or below
normal for this time of year, so this rain should not bring any
rivers to flood.

Strong thunderstorms could produce localized rainfall totals over an
inch and lead to localized ponding of water. Rainfall totals will
probably vary substantially over short distances.


.GRR Watches/Warnings/Advisories...
MI...Beach Hazards Statement until noon EDT today for MIZ056-064-071.

LM...Small Craft Advisory until noon EDT today for LMZ844>846.



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