Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 270729

Area Forecast Discussion
National Weather Service Grand Rapids MI
329 AM EDT WED JUL 27 2016

Synopsis/Short Term/Long Term/Marine

Issued at 329 AM EDT Wed Jul 27 2016

A slow moving cold front will result in scattered thunderstorms
today, mostly north of I-96. It will be very warm with highs from
the mid 80s to near 90. A wave on the front will slow its push
south tonight and as the wave on the front moves across Lower
Michigan Thursday, it will result in more widespread showers and a
few thunderstorms. Due to the clouds and showers it will be cooler
with highs in the lower 80s. After the frontal wave moves south
and east of the area Friday skies will start to clear as Canadian
high pressure builds in behind the front. The weekend will be
partly cloudy with near normal temperatures thanks to that
Canadian high.


.SHORT TERM...(Today through Friday)
Issued at 329 AM EDT Wed Jul 27 2016

We are tracking a slow moving cold front and the associated
thunderstorms for today. the front will only reach near I-96 by
evening. Any thunderstorms will remain near and north of the
front. The front will then stall near I-96 tonight as a surface
wave tracks along the front, crossing Lower Michigan Thursday.
Areas near and north of I-94 could see a decent amount of rain
Thursday if the ECMWF 00z run is correct as it results in over
and inch of rain over a large area of our central and northern
CWA. Since the models have been back and forth on this idea I have
50 pct pops for tomorrow but this may have to increased if the
latest ECMWF is to be believed.

That system clears the area Friday bringing clearing skies and
near normal temperatures.

.LONG TERM...(Friday night through Tuesday)
Issued at 329 AM EDT Wed Jul 27 2016

Zonal flow will transition to more of an upper trough by late this
week. But that doesn`t necessarily mean that we`ll see rain. Indeed,
a sfc high over eastern Ontario and Quebec will produce a relatively
dry northeast flow Friday night through Monday which should keep
pcpn pushed south of the cwa. GFS and ECMWF show a few short waves
moving across Indiana and Ohio over the weekend, but almost all of
the pcpn is shown south of the cwa. We`ll keep a slight chance of
pcpn in south of I-94 Friday night and Saturday, but more than
likely we`re looking at dry wx through Tuesday.

Highs will mostly be above normal due to the lower dewpoints and the
ridge to the northeast. Highs in the lower 80s Saturday will climb
to the mid to upper 80s Sunday through Tuesday.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1153 PM EDT Tue Jul 26 2016

There may be some mvfr fog at JXN toward sunrise, otherwise fair
wx is expected through the period.


Issued at 329 AM EDT Wed Jul 27 2016

No major issues seen through Saturday.


Issued at 150 PM EDT Tue Jul 26 2016

No river flooding is expected into next week. There is a chance of
rain in the forecast Wednesday into Saturday night. Total rainfall
should be under an inch. River levels are around normal for this
time of year. Even with the precipitation, no rivers should approach
flood level.


.GRR Watches/Warnings/Advisories...


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