Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 220513

Area Forecast Discussion
National Weather Service Grand Rapids MI
113 AM EDT MON AUG 22 2016


Issued at 322 PM EDT Sun Aug 21 2016

Showers and a few thunderstorms will be ending this evening, as a
storm system departs the area. Skies should clear tonight allowing
temperatures to fall into the upper 40s over northern areas and to
the mid 50s for the rest of the area. It will be mostly clear Monday
into Tuesday with a slow warming trend. The next frontal system will
bring showers and thunderstorms back to the area later Wednesday
into Thursday.


Issued at 1036 PM EDT Sun Aug 21 2016

Last of precipitation has dissipated coincident with diurnal
cooling and a pronounced upper potential vorticity max exiting
east of the area. Will drop rain chances and adjust clouds to
reflect this.


.SHORT TERM...(This evening through Tuesday night)
Issued at 322 PM EDT Sun Aug 21 2016

No issues in the short term after the convection ends this evening.
Temperatures will be a little below normal tonight and Monday. High
pressure will move across the region Monday and Tuesday bringing
mostly clear skies and temperatures slowly warming to near to
above normal levels by mid week.

.LONG TERM...(Wednesday through Sunday)
Issued at 322 PM EDT Sun Aug 21 2016

Medium range models continue to support a cold front crossing the
region Thursday.  The upper wave appears to shear out, so the
potential for severe weather looks low, but the chance of showers and
a few storms look good.  Peak chances will move into SW MI Wednesday
night ahead of the front, with lessening chances into Thursday as
the front passes.  It this point, it appears the front comes through
Thursday morning.

A pleasant period is expected from Thursday night through Saturday,
with high pressure in control. The next chance of rain comes in
Saturday night at the soonest.  The models are not in good agreement
with this as the GFS ensemble is the quickest bringing moisture in
from the southwest, while the operational GFS and the ECMWF are
slower.  We will monitor trends, but at this point will have POPs
starting Saturday night into Sunday, but next weekend could end up

As for temps, we will see warmer than normal temps Wed and Thu, but
then a cooler period behind the front for Friday and Saturday.  It
appears near normal temps arrive again by Sunday.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 112 AM EDT Mon Aug 22 2016

Skies will be mostly clear the rest of the night. Sct-bkn diurnal
vfr cu is expected this afternoon.


Issued at 1036 PM EDT Sun Aug 21 2016

After coordination with IWX...will continue the SCA until its
expiration of 1 AM. This is based largely on continued 3-4 foot
waves being reported farther south and on reports of some close
calls at the piers earlier today.


Issued at 322 PM EDT Sun Aug 21 2016

Strong thunderstorms produced swaths of heavy rainfall that totaled
up to 1 to 2 inches on Saturday. The Vicksburg area in southern
Kalamazoo County received around 1 inch of rainfall, which has
resulted in additional rises on the Portage River near Vicksburg.
A Flood Warning remains in effect for the Portage River near
Vicksburg through Wednesday morning.

Only light scattered showers are expected this afternoon and
evening. Dry weather with plenty of sunshine is expected Monday and
Tuesday. The next best chance for appreciable rainfall will be late
Wednesday into Thursday.


.GRR Watches/Warnings/Advisories...


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