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Area forecast discussion 
National Weather Service Green Bay WI
322 am CDT Monday Apr 27 2015

Forecast discussion for routine morning forecast issuance

issued at 320 am CDT Monday Apr 27 2015

Dry and mild this week.

Expansive and complex blocking is in place across much of Canada...
the central and northern Continental U.S....and the North Atlantic. Westerlies
advancing eastward from the Pacific will gradually break down The Block from
west to east. But they probably won't reach the forecast area until
at least the the entire work week will be spent under
the influence of The Block.

There is little chance for significant precipitation as long as
The Block encompasses the area. As a result...precipitation
amounts for the period are likely to end up well below
normal...and some areas may not get any rain at all. Medium range
models are trending toward a lower amplitude pattern with the main
westerlies near the U.S./Canadian border after next weekend. That
would be more favorable for precipitation than recent patterns. But
it is also pretty far out into the model confidence in that
actually occurring is limited.

The dry air mass across the area will result in near to modestly
above normal temperatures during the day...yet allow readings
to fall to a little below normal at night. East flow will keep it
considerably cooler near the lake at times.

Short Tuesday
issued at 320 am CDT Monday Apr 27 2015

Some moisture rotating around western flank of upper low near New England will
brush through eastern WI at times today...resulting in patches of high
and middle clouds...and perhaps a little middle-day convective
cloudiness. Weakening shortwave will be approaching from the west Tuesday afternoon.
That should lead to few more clouds than today in the west. But precipitation
with the feature will probably wipe-out before reaching the area.
Stayed close to blend of guidance for maximum and min temperatures.

Long term...Tuesday night through Sunday
issued at 320 am CDT Monday Apr 27 2015

Generally dry during this part of the forecast. Temperatures
should be within a few degrees of normal for the remainder of the
work week...followed by a bit of a warming trend for the weekend.

Models continued to bring a middle level trough across Wisconsin for
the middle of the week...but most solutions indicated no quantitative precipitation forecast in
the forecast area so have kept the forecast dry as this system
passes. Once the trough axis is east of the state a cut-off system
was forecast to develop and then move south...but quantitative precipitation forecast with this
cut-off remained east of Wisconsin. A middle level ridge then moves
into the region behind the departing trough...but another trough
will quickly move in behind it. The trough combined with a surface
trough/frontal boundary will bring a chance for showers to central
and north central Wisconsin on Friday...with slight chances for
the rest of the area. The slight chances continue across most of
the area for Friday night. Warm advection combined with some middle
level short wave energy will bring chances for showers to the
entire area on Sunday.

Aviation...for 12z taf issuance
issued at 320 am CDT Monday Apr 27 2015

Mainly VFR conditions expected through the taf period...along
with very favorable flying weather. The exception may be some
brief MVFR ceilings in eastern WI middle-day today as convective cloudiness

Grb watches/warnings/advisories...


short term.....Skowronski

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