Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 112351

Area Forecast Discussion
National Weather Service Green Bay WI
651 PM CDT Fri Aug 11 2017

Updated aviation portion for 00Z TAF issuance

.SHORT TERM...Tonight and Saturday
Issued at 210 PM CDT Fri Aug 11 2017

Cyclonic flow over the region were keeping clouds around along
with cooler afternoon temperatures. Various models including the
short range runs continue to develop isolated light showers
across the area during the remainder of the afternoon, but so far
only spots of drizzle or sprinkles were noted. Local radars show
light showers over the area, with more numerous showers with
isolated storms over Lower Michigan. The HRRR even produces a few
light showers over Door County late tonight, where the cyclonic
flow may linger a bit longer and some instability contribution
with the cooler air flowing over the Great Lakes region. Will
leave dry for now due to limited coverage of showers this

High pressure approaching from the west along with drier air on
northwest winds were gradually eroding the clouds or increasing
the base height over central and north central Wisconsin early
this afternoon. Appears this trend of clearing is lagging so will
slow down this trend this afternoon and evening across northeast

Eventually clearing skies and diminishing winds will prevail
across much of the area, and allow temperatures to fall.
Typical Climatological cool spots of central and north-central
Wisconsin may make a run toward the upper 30s to around 40.

High pressure settling over the area Saturday will allow abundant
sunshine and allow temperatures to return closer to normal.

.LONG TERM...Saturday Night Through Friday
Issued at 210 PM CDT Fri Aug 11 2017

A fairly stable pattern will be in place across North America over
the next week, consisting of a potent ridge slowly moving east over
central Canada.  Will therefore see mainly quiet conditions until
this ridge passes to our east, which will allow the deep layer flow
to turn back to the southwest and increase precip chances.  Plenty
of differences in the models by this time, and prefer a solution
closer to the gfs.

Saturday night through Monday...Conditions will start out quiet on
Saturday night with a large area of high pressure in control.  Dry
conditions will probably continue into Sunday morning, but clouds
will be on the increase as weak shortwave energy moves into the
region.  This shortwave will move across the region during Sunday
afternoon into Sunday night.  Progged soundings indicate that the
atmosphere will struggle to saturate below 700mb, so cannot see much
more that scattered light showers and sprinkles during this time.
Clouds will then decrease behind the shortwave for late Sunday night
into Monday morning.  Scattered high based cu is likely to form on
Monday, but precip chances look too low to mention at this time.
Comfortable temps near normal over this period.

Rest of the forecast...High pressure is then projected to stick
around for Tuesday into much of Wednesday.  The flow will be
shifting more to the southwest aloft during this time, so think
precip chances will gradually ramp up late Wednesday into Thursday.
Temps and humidity levels will also be slowly increasing during this

.AVIATION...for 00Z TAF Issuance
Issued at 651 PM CDT Fri Aug 11 2017

AVIATION...MVFR ceilings will continue at least through midnight
near the Michigan border and also across Door county and the bay.
The remainder of the area should have clearing overnight. Good
flying weather expected Saturday through Sunday with just some
ground fog possible early Sunday.



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