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Area forecast discussion 
National Weather Service Green Bay WI
611 am CDT Sat Oct 10 2015

Updated aviation portion for 12z taf issuance

Short Sunday
issued at 303 am CDT Sat Oct 10 2015

Mostly clear skies and light winds have caused some patchy frost
and patchy fog across portions of central and north central
Wisconsin early this morning. Since headlines are no longer being
issued for frost across the north this is not much of a
concern...with temperatures across central Wisconsin likely
remaining above headline criteria for the rest of the morning.
Regarding fog...visibilities are jumping rather wildly with only a
few locations experiencing fog. Therefore will continue to hold
off on products unless an Special Weather Statement is necessary should the fog increase
in intensity or persistence.

High pressure will be in control of the weather during the
weekend...with winds becoming southwest today as high pressure
sinks south and the pressure gradient increases on the backside of
the high. After a cool start this morning...highs should recover
into the lower to middle 60s during the afternoon hours as warm
air advection commences across the western Great Lakes with
abundant sunshine. The increased pressure gradient will also lead
to breezy conditions across the western Great Lakes today.

Despite mostly clear skies again tonight...a fairly tight pressure
gradient should keep surface winds at 5 to 10 knots. This should
keep overnight lows around 50 degrees across northeast Wisconsin.

Sunday will be even warmer as continued warm air advection pushes
850 mb temperatures to around 20 celsius. The warm air and
abundant sunshine will push daytime highs well into the 70s away
from the lakes...with 80 degree readings not out of the question.

Long term...Sunday night through Friday
issued at 303 am CDT Sat Oct 10 2015

The main concern in the long term is the precipitation forecast
on Monday.

Models showed a strong upper level short wave moving across
Wisconsin Sunday night into a cold front also makes
its way through the state. The system should not be able to tap
into Gulf moisture will be lacking. As a result of
this...probability of precipitation are no higher than chance category for Monday into
Monday evening...and they are confined to north central Wisconsin
closer to the surface low and upper cyclone. Westerly flow will be
quite strong behind the cold front with good a windy
day is in store on Monday. High temperatures on Monday will range
from just a few degrees above normal across north
nearly 10 degrees above normal in east central and far northeast

Once the main trough passes the upper level flow across the
region is forecast to amplify slightly from west-northwest to
northwest. The initial blended guidance only produced some slight
chance probability of precipitation late in the week across the north...but nothing more.
Temperatures in this flow regime should generally be a little
below normal.

Aviation...for 12z taf issuance
issued at 611 am CDT Sat Oct 10 2015

Patches of high clouds will affect the forecast area
VFR conditions are expected at most of the taf sites. Some MVFR
fog is possible at County Warning Area/rhi but should dissipate quickly with
sunrise. S-SW winds will increase today...with gusts to 20 to 25
kts anticipated during the late morning and afternoon. Have kept
low level wind shear in the tafs for this evening and into the SW
winds increase to 45 kts off the surface.

issued at 303 am CDT Sat Oct 10 2015

As a surface ridge slides east this morning...gusty winds are
expected to develop by middle morning and create conditions hazardous
to small craft. Persistent southwest flow will cause building
waves...with the highest waves near northern Door County. Winds
and waves should diminish slightly this evening and
overnight...however they should be enough to warrant the
continuance of the Small Craft Advisory near northern Door
County. Another round of gusty winds and hazardous conditions are
expected for all of Lake Michigan on Sunday and likely continue
into the early part of the week. While small craft advisories
could easily be issued through early in the week...will extend the
current ones around Door County into Sunday at this time.

Grb watches/warnings/advisories...


Short term.....Kurimski

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