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835
FXUS63 KGRR 151928
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
327 PM EDT Sun Oct 15 2017

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

.SYNOPSIS...
Issued at 327 PM EDT Sun Oct 15 2017

A few showers will linger through the overnight hours as one more
wave of low pressure pushes through the area. The rain will be very
light with only small amounts expected.

Conditions will improve on Monday with clearing skies and lighter
winds as high pressure builds in over the area. The dry weather will
last through the upcoming week. Temperatures will gradually warm
through the period back to above average levels.

&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 327 PM EDT Sun Oct 15 2017

We will be letting the wind advisory go early this afternoon with
the winds not living up to their potential. Otherwise the only
forecast challenge is rain chances into early Monday, and frost
potential for tonight up North.

A few very light showers continue to rotate through the area this
afternoon as the upper flow has become cyclonic and the upper cold
pool has moved into the region. These are just a nuisance today with
the somewhat gusty winds, compared to the flooding rains from
yesterday.

We will likely see an uptick in the showers tonight along the
lakeshore. This is due to the upper short wave over MN this
afternoon that will zip over the area overnight tonight. Lake effect
rain showers will remain possible with plenty of over-lake
instability with delta t/s of mid-upper teens C. This short wave
will supply some mid level moisture and better instability over the
lake effect from the NNW. Inland areas could see a few light showers
also.

With the additional cloud cover, frost does not look to be as likely
as once thought up across Central Lower. We have some patchy frost
up toward Leota, however we do not expect this will be significant
enough or widespread enough to need a headline.

After the short wave moves out Monday morning, we will see clearing
skies. These clear skies will last the remaining portion of the
short term through Tuesday night. Temps will be a little cool Monday
afternoon and Monday night. Temperatures will moderate then beyond
Monday.

.LONG TERM...(Wednesday through Sunday)
Issued at 327 PM EDT Sun Oct 15 2017

A fairly uneventful long term period looks to be in store as zonal
upper flow will prevail the entire time. The zonal flow will bring
dry weather from Wednesday through Saturday where no precipitation
is expected. Rain returns to the forecast for Saturday night into
Sunday, however the prospects are rather low given the upper wave is
weakening as it moves our direction.

As far as temperatures go we will be well above normal as the
surface flow will be southerly the bulk of the time. 850mb
temperatures will be in the lower to middle teens C, which should
produce highs in the 70s most likely. We have upper 60s to low 70s
in the forecast but these may trend upward slightly as we go
forward. Normal highs for this time of year are in the upper 50s, so
we will be at least 10 degrees above normal late in the week.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 204 PM EDT Sun Oct 15 2017

MVFR conditions are widespread across Western Lower Michigan at
18z, but an improving trend should occur later this afternoon and
evening. Ceilings in the 1,000-2,000ft range should lift into the
2,000-3,000ft range after 21z or so. After 00z, most areas should
improve to VFR. There will be showers towards Lake Michigan that
continue all the way towards 09z tonight, but they should be on a
gradual tapering off trend as we head into Monday. VFR weather is
expected late tonight and Monday morning.

The gusty west to northwest winds will also be on a tapering off
trend with light winds expected overnight. The windiest conditions
(15-30 knots) will persist through about 23z, after which time the
wind should lose its gustiness and fall below 10-12 knots.


&&

.MARINE...
Issued at 327 PM EDT Sun Oct 15 2017

Gale warning remains in effect this afternoon, and is working out
nicely with most coastal sites above criteria, and waves over 10
feet. This will come down this evening.

The other threat for the nearshore waters are waterspouts. With
quite cool air coming in over the lake, and the wave moving overhead
tonight, that will be conducive for the threat of waterspouts. The
weakening winds will also help the cause. This threat will end Mon
morning as the wave moves by.

&&

.HYDROLOGY...
Issued at 327 PM EDT Sun Oct 15 2017

A widespread 1 to 3 inches fell across the majority of the area,
with the exception of Ludington to Clare. Greater totals of 3 to 5
inches were focused south of Holland-Lansing and west of Jackson.
Southern Van Buren, central Kalamazoo, and northern Calhoun counties
received a swath of 5 to 7 inches. Isolated amounts of 8 or 9 inches
fell around Decatur, Lawton, and west of Portage. And we`re not
talking about snow here.

The scope of this weekend`s rainfall in Southwest Michigan is
reminiscent of the tropical rains received on August 15-16, 2016.
However, the magnitude of the highest totals today is greater (the
highest totals in the 2016 event fell by South Bend). At the
Kalamazoo airport, greater than 6 inches fell, which is the greatest
2-day total (midnight-to-midnight) recorded there since the remnants
of Ike came through in September 2008.

This weekend`s rain fell over a longer duration than Aug 2016 and
had relatively dry preceding conditions, so flooding is not as bad
as it could have been. Nonetheless, a number of road closures
occurred due to flooding across Van Buren and Kalamazoo, a small dam
failed near Paw Paw (with little to no impact to the downstream
Maple Lake, which was drawn down 4 feet last week for the winter),
and no doubt some homes and businesses were affected as well. Some
river points in the Kalamazoo and Grand river basins have risen or
are expected to rise above bankfull, and reaching flood stage is not
anticipated (except for minor flooding occurring on the Portage
River near Vicksburg). With a dry week ahead, rivers will run their
course without further exacerbation.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...Gale Warning until 8 PM EDT this evening for LMZ844>849.

&&

$$

SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...Duke
AVIATION...Duke
HYDROLOGY...CAS
MARINE...NJJ