Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 211858

Area Forecast Discussion
National Weather Service Grand Rapids MI
300 PM EDT SAT MAY 21 2016

Synopsis/Short Term/Long Term/Marine

Issued at 300 PM EDT Sat May 21 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 will approach
the eighty degree mark by Monday and Tuesday. The next chance for
showers and thunderstorms will come Wednesday through late week.


.SHORT TERM...(This evening through Monday night)
Issued at 300 PM EDT Sat May 21 2016

Fcst concerns in the near term remain minimal as high pressure
will continue to dominate the wx pattern through Monday. Most of
the cloud cover tied to the sfc trof/upper system is now east/se
of our area.

12z short range guidance consensus time height rh
x sections/numerical guidance suggest skies will be mostly clear
through most of the short term fcst period. However an area of mid
to high cloud cover over the Lake Superior region this afternoon
will continue to move sse across our area tonight.

Temps will continue to moderate gradually through Monday and reach
the lower to middle 70`s again tomorrow and will approach the
eighty degree mark on Monday.

.LONG TERM...(Tuesday through Saturday)
Issued at 300 PM EDT Sat May 21 2016

An unsettled pattern will be setting up over the region for the long
term period.  Shower and thunderstorms will be on the increase. Some
of the rain will be locally heavy as well.

To start...a mid level ridge will be overhead on Tuesday.  This
system will likely keep the region dry for one more day.  Warm air
advection develops as the ridge tracks east.  As a result moisture
will be on the increase Tuesday night into Wednesday with values
climbing to well over an inch.  Instability pushes in...especially
as we go through the day on Wednesday with a low level jet nosing
in.  This could support numerous showers and thunderstorms.

The pattern then stays about the same as we go into the beginning of
the Memorial Day weekend.  The main reason for this is because the
upper level flow becomes nearly parallel to the axis of the moisture
and instability.  High pwat values with some low level jets along
with instability...should lead to several episodes of showers and


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 116 PM EDT Sat May 21 2016

Low level moisture remains limited through the period. As a result
this is forecasted to keep conditions VFR. Will need to monitor
the late night fog potential. With Lake MI water temps climbing
into the 50s along the lakeshore...and overnight lows forecasted
to fall into the upper 40s to low 50s...some potential for patchy fog
exists. For now the risk is too low to include in the forecast.


Issued at 300 PM EDT Sat May 21 2016

High pressure will remain in control of the weather pattern
through the weekend and Monday and result in minimal wave action
with wave heights aob 2 ft through then.


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...


SHORT TERM...Laurens
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