Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 221140

Area Forecast Discussion
National Weather Service Grand Rapids MI
740 AM EDT SUN MAY 22 2016


Issued at 243 AM EDT Sun May 22 2016

High pressure will remain in control of the weather pattern
through Monday and result in mostly clear skies and a continued
moderating trend of temperatures. High temperatures close to 80
are expected for much of the area through Friday, which is 5 to
10 degrees above normal for this time of year. Chances for
showers and thunderstorms return late Tuesday and persist through
Saturday with the best chances Wednesday and Wednesday night.


.SHORT TERM...(Today through Tuesday)
Issued at 243 AM EDT Sun May 22 2016

No impact weather is anticipated. I introduced a slight chance
for showers and thunderstorms Tuesday afternoon, which is a
slightly earlier onset than the previous forecast. Otherwise, no
noteworthy changes were made. Would not be surprised to see us
reaching the low 80s both Monday and Tuesday afternoons, but have
kept the forecast closer to 80 for now.

.LONG TERM...(Tuesday night through Saturday)
Issued at 243 AM EDT Sun May 22 2016

The long term portion of the forecast continues to look rather
unsettled and warm for Lower Michigan. We will see the long wave
upper ridge axis shift east of the area by Tue night. This will
allow for a southwest flow aloft to become established over the area
all of the way from the desert southwest.

Short wave troughs will be riding this sw flow aloft up into the
area. Low level srly flow will provide for sufficient moisture
advection from the Gulf of Mexico. We will see intervals of showers
and storms beginning Tuesday night and lasting right on through
Saturday. This does not mean it will be raining all of the time. The
threat of rain will be there everyday, however the timing of
individual waves is impossible to fcst at this time.

The core of the jet stream will remain to our west through the
entire long term. This will ensure that temps will remain warm
through the period with the low level srly flow remaining locked in
place. If enough peaks of sun occur between waves of rain, 80
degrees will be attainable on multiple occasions.


.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 740 AM EDT Sun May 22 2016

Very high confidence for VFR conditions through the period. We
will see clouds with bases at or above 9000 ft move south out of
the area today with clear conditions afterwards. Winds will be
light much of the day although the MKG terminal will have somewhat
stronger winds from the northwest associated with the lake breeze.


Issued at 243 AM EDT Sun May 22 2016

No concerns in the short term. However, winds from the south will
increase Monday into Monday night allowing waves to build. Higher
waves are expect mainly north of Muskegon where the fetch will be
more favorable.


Issued at 1059 AM EDT Sat May 21 2016

There are no river advisories to mention in todays discussion. The
extended period of dry weather has proven beneficial and all sites
are now below bankfull. Dry conditions will continue through at
least Monday. Chances for precipitation increase by Tuesday of
next week and may very well extend through mid and late week.
Model guidance has trended much further west with the upper level
disturbance in time, ultimately elongating the stream of moisture
from the Gulf Coast. Therefore, while moisture levels increase to
1.5-2 times their normal values, the duration and magnitude of
next week`s precipitation is still uncertain. River levels are now
running near to slightly above normal and recent green up may help
to mitigate additional flood potential.


.GRR Watches/Warnings/Advisories...


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