Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 301922
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
322 PM EDT MON MAY 30 2016

LATEST UPDATE...
Synopsis/Short Term/Long Term/Marine

.SYNOPSIS...
Issued at 322 PM EDT Mon May 30 2016

The pleasant weather will continue tonight through Tuesday night
with comfortable temperatures and humidity, along with dry
conditions.  Showers and storms will return for Wednesday and
Wednesday night.  A few for these storms could be strong.

Mostly dry weather should move back in for Thursday and Friday, but
there appears to be another good chance for rain into the weekend.
Daytime temperatures will remain in the mid 70s to lower 80s Tuesday
through Saturday, but then it should become cooler for Sunday and
Monday.

&&

.SHORT TERM...(This evening through Wednesday night)
Issued at 322 PM EDT Mon May 30 2016

The mid week system will be moving in slower than expected as it
runs into the ridge over the eastern U.S.  Will back off on rain
chances for Tuesday night, with the bulk of the weather arriving
Wednesday, then exiting late Wednesday night.

Surface high pressure will continue to bring fair weather to the
region along with pleasant temps and humidity.  It will begin to
move to our east by Tuesday, but will still just be over Lake Huron
by the end of the day, and to Lake Ontario by daybreak Wednesday.
This shift east will help reduce the subsidence and allow mid/hi
clouds to move in by Tuesday afternoon.  But the easterly flow
around the high will keep the low levels dry until Wednesday.  With
minimal instability expected, we no longer expect measurable pcpn
for Tuesday night.  We could see a few sprinkles come from the mid
deck at best.

Wednesday and Wednesday night will bring a return to a chance of
showers and storms.  A slow moving surface cold front will only be
moving into Western WI early in the day and this front will not
reach the CWA until Wed evening.  So the day should start out with
some sun, but a solid pool of low level moisture arrives later in
the day as the front approaches.  Storms will be likely, but severe
weather should remain minimal. Instability does not appear to be too
great as the front moves into mid and upper 50s dew points over the
area. A low level jet moves NE across WI Tuesday night, but it is up
into Ontario by Wednesday.  Our storms will have the right entrance
region of the upper jet to work with.  This feature comes through
late afternoon into the evening, when some stronger storms will be
possible.  The convective nature of the pcpn will cause variable
rain totals, but generally most areas should see a quarter to half
inch by daybreak Thursday.

.LONG TERM...(Thursday through Monday)
Issued at 322 PM EDT Mon May 30 2016

The last vestiges of the rain on Wednesday night will be moving out
at the beginning of the long term period Thursday morning. The cold
front will just be exiting the far SE corner of the CWFA at that
time. The upper flow will remain anti-cyclonic and a sfc ridge axis
will then build in across the state. This should hold through
Friday, and allow for cooler and dry conditions to be the rule.

We will see even cooler, and unsettled weather move in for next
weekend and early next week. Models and their ensemble means are in
good agreement in bringing lower heights across the area for that
time frame. We will see a couple of stronger short wave troughs dive
SE into the Great Lakes region. This will result in chcs of rain
showers at times and max temps struggling to reach 70.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 141 PM EDT Mon May 30 2016

VFR conditions are expected through the entire 18z fcst period.
Some cumulus clouds are developing inland from Lake Michigan early
this afternoon. These clouds are based around 5k ft. Some
additional development will occur this afternoon, with even a
sprinkle not out of the question at KLAN and KJXN. This should not
cause any impacts to aviation interests. Clouds will dissipate
quickly this evening toward sunset.

Winds will go light also around sunset. Fog potential looks rather
minimal for tonight even with clear skies and light winds. The
atmosphere is rather dry, and the nights are rather short at this
time of the year.

Some mid clouds around 15k ft will float in on Tue. We will also
see at least a little diurnal cumulus development toward
afternoon. Any cloud bases will be 4-5k ft and above.

&&

.MARINE...
Issued at 322 PM EDT Mon May 30 2016

A rather quiet period is expected on the lake through the short
term, with one exception.  Southerly winds ahead of Wednesday`s
front should cause rough conditions around the points into Wednesday
afternoon.  At this point it appears this will remain below small
craft criteria however.

Until then, winds will generally remain under 15 knots and mainly
a southeasterly offshore flow.

&&

.HYDROLOGY...
Issued at 211 PM EDT Mon May 30 2016

River levels are currently stable and near normal for this time of
year. No significant flooding or precipitation events are expected
this week. Total basin-average rainfall Wednesday afternoon into
Thursday will likely be less than 0.75 inches. This would result in
only minor rises on area rivers.

&&

.GRR Watches/Warnings/Advisories...
MI...None.
LM...None.
&&

$$

SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...EBW
MARINE...JK



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