Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 290800

Area Forecast Discussion
National Weather Service Green Bay WI
300 AM CDT FRI JUL 29 2016

Forecast discussion for routine morning forecast issuance

.SHORT TERM...Today...Tonight...and Saturday
Issued at 300 AM CDT Fri Jul 29 2016

Slow moving short wave trough continues to track over mainly the
south half of the state and producing scattered showers and
isolated storms over east central Wisconsin early this morning.
Pieces of energy in this trough were generating spotty convection
over the south half of the state. First piece will be departing
eastern wisconsin this morning while a second piece was over west
central Wisconsin. This second area is progged to pass over
southern wisconsin this afternoon. With pwats still near 1.50
inches and a very slow movement with the convection, isolated
heavy rainfall will continue with a few of the these showers and
storms early this morning.

Forecast challenge today continues with the convection trend today
starting this morning. Surface dewpoints were falling across
North Central Wisconsin early this morning as surface high
pressure builds into the area. But since surface dewpoints still
near 60 under the trough, will linger isolated shower and storm
mention today over east central this morning and then areas south
of highway 10 this afternoon and early evening. Anticipate a
little drier air to work south today but progs still indicating
upper 50 dewpoints for GRB though Saturday.

Models divert on additional isolated shower activity for Saturday
and the water vapor loop upstream showed weak waves upstream in
the noisy northwest flow. Upper heights do begin to increase later
Saturday so will continue with the dry forecast for now.

Clouds lingering this morning over much of central Wisconsin and
east central Wisconsin may hold back temps again today. But the
potential of breaks in the clouds occurring later morning between
the subtle pieces of energy in the trough prevent lowering max
temps at this time.

.LONG TERM...Saturday Night Through Thursday
Issued at 300 AM CDT Fri Jul 29 2016

Fairly zonal flow at 500mb will dominate the weather pattern
through the period. At the surface, high pressure will bring
dry conditions Saturday night through Monday. Models diverge on
the evolution of convection across the Upper Midwest and Great
Lakes region Monday night into Tuesday. Since the 00z ECMWF model
has been more consistent than any other model for this period,
will trend toward the ECMWF with a round of storms moving across
the area later Monday night into Tuesday morning.

Beyond Tuesday, confidence is low on timing of convection Tuesday
night through Wednesday night. Based on the 00Z ECMWF, there is
a better chance of thunderstorms Thursday afternoon and Thursday
night. High temperatures should be above normal through much of
the period.

.AVIATION...for 06Z TAF Issuance
Issued at 1132 PM CDT Thu Jul 28 2016

Weak upper level disturbances are expected to move E-SE across
southern sections of the Great Lakes region through Friday.
Isolated to scattered showers will linger mainly along and south
of Route 29 and south of Sturgeon Bay overnight and over the
southern third of WI on Friday. Low-end VFR conditions are
forecast for most of northeast WI taf sites tonight into Friday
with the exception of RHI where mostly sunny skies and unlimited
cigs/vsbys are expected. High pressure is then progged to build
south into WI Friday night and bring drier air to the region.



LONG TERM......Eckberg
AVIATION.......AK is the U.S. government's official web portal to all federal, state and local government web resources and services.