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Area forecast discussion 
National Weather Service Green Bay WI
700 PM CDT Tuesday Jun 30 2015

Updated aviation portion for 00z taf issuance

Short term...tonight and Wednesday
issued at 159 PM CDT Tuesday Jun 30 2015

Dry weather has returned to NE Wisconsin this afternoon as the
last of the shower activity moved into Lake Michigan with the
departing upper level trough.

Skies should become mostly clear tonight as strong subsidence and
drier air moves over the state. Was reluctant to have clear skies
as models show residual upper level moisture...and current
satellite images have high clouds streaming in from the northern
plains. Chilly temperatures are expected with the cold spots in
northern Wisconsin possible falling just under 40
degrees...especially if cloud happen to clear out. Patchy fog
looks less likely overnight as much of the area has seen drier
than previously forecasted conditions. With less
some clouds and stronger winds than the past few nights just above
the surface...fog development should stay under control.

A shortwave swinging through the exiting system to our east may
cause thicker cloud cover to brush Lakeshore locations on
Wednesday. Otherwise...high pressure will build into the Great
Lakes states on Wednesday with mostly sunny skies prevailing. High
temperatures will be below normal as cold air advection continues over NE WI and models
show 850mb temperatures dropping through the day. Trended towards cooler
solutions for Wednesday which matched well with the latest MOS

Long term...Wednesday night through Tuesday
issued at 159 PM CDT Tuesday Jun 30 2015

Northwest upper flow continues into the first part of long term
but some flattening of flow forecast as trough moves into western
then central Canada.

Sunday night into Monday appears to be the time period for next best
chance of precipitation as Canadian trough moves toward western lakes. Timing
of system and surface reflection still uncertain during this
period...GFS is faster than European model (ecmwf) will continue medium
chance probability of precipitation for later Sunday evening into Monday.

Temperatures through period a blend of best performing guidance but adjusted
up a bit around waters of Green Bay/Door County.

Aviation...for 00z taf issuance
issued at 652 PM CDT Tuesday Jun 30 2015

Low clouds (mvfr and low-end vfr) were eroding from west to east
due to the arrival of a Canadian high pressure system early this
evg. Clearing will probably be delayed along the Lakeshore until
later in the north winds will bring low clouds from
the Central Upper Peninsula of Michigan southward into the region.
Will monitor the timing of the clearing for the mtw taf site
this evening.

Tough call on fog potential over NC/c WI overnight. The high
pressure system will be ridged over the region overnight...
resulting in light surface winds...and the ground is likely
still moist from yesterdays rain. However...the incoming
Canadian air mass is quite dry and boundary layer winds are
expected to be around 15 kts. For now...will only mention
some light fog at the rhi taf site...and leave it out elsewhere.

Aside from the lkshr areas this evg...and patchy fog NC WI
overnight...expect prevailing VFR conditions through the taf

Grb watches/warnings/advisories...


Short term.....Allen
long term......jkl

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