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Area forecast discussion 
National Weather Service Green Bay WI
1141 PM CDT sun may 24 2015

Updated aviation portion for 06z taf issuance

Short term...tonight and Monday
issued at 255 PM CDT sun may 24 2015

This afternoon...low pressure was noted across northeast Nebraska
with a warm front extending eastward across central Iowa into
northern Illinois. This low pressure system will approach the area
tonight as the warm front lifts northward. It will be a wet night
as 850mb low level jet expected to increase to 40 to 50 knots.
Widespread rain is expected this evening due to the isentropic
lift over the front. Some thunderstorms are possible later
tonight and on Memorial Day across the southern half of the
forecast area...but they are not expected to be severe. The rain
will gradually taper off later tonight into Memorial Day morning
as scattered showers or drizzle...except over the north where
shower chances are highest on Memorial Day near the boundary.
Some of the latest guidance suggesting some locations across
north- central and northeast Wisconsin could see over an inch of

It will turn windy and warm across portions of northeast and
east-central Wisconsin where wind gusts could reach 30 to 35 miles per hour
and temperatures warm to near 80. Meanwhile...low clouds and
showers could keep the far north (vilas County in the upper 50s
and lower 60s.

Long term...Monday night through Sunday
issued at 255 PM CDT sun may 24 2015

The upper level flow continues to be from the southwest through
Wednesday morning. Jet streaks lifting out of the upper trough
lifting northeast from the plains states will produce occasional
showers and thunderstorms until the trough moves through.

Northwest upper flow and the approach of a flat upper ridge
should provide for mostly dry weather Wednesday and Thursday. A
more substantial upper trough and associated surface cold front
are forecast to arrive Thursday night or Friday (depending on
which model you believe). It should be be followed by cool and dry
weather for Saturday and Sunday.

Highs and lows should be above normal Tuesday through Friday
before dropping to 5 to 8 degrees below normal Saturday and
Sunday. There is some potential for frost in northern Wisconsin
Friday and Saturday night as the air arriving from Canada is
forecast to be very dry with dewpoints in the 30s and 40s.

Aviation...for 06z taf issuance
issued at 1135 PM CDT sun may 24 2015

Showers will continue to lift north across the region
overnight...with IFR conditions expected at most locations due to
the rain and persistent east to southeast flow off Lake Michigan.
There may be a brief break in the precipitation in some areas late tonight
into early Monday before an upper level disturbance and warm front
bring more showers and isolated thunderstorms to the region. A dry slot is
expected to bring an end to the showers over the southeast half of the
forecast area in the afternoon. Conditions should improve to
MVFR/local VFR within the dry slot...and SW winds will gust to
around 30 kts at the grb/atw/mtw taf sites. Scattered thunderstorms may develop
near a cold front in central WI by late afternoon or early evg...
and may track into ec WI during the evg...but confidence is too
low to mention at the southern taf sites right now.

Will keep low level wind shear in the forecast winds aloft veer from
southeast to SW and increase to 35 to 40 kts. Conditions should improve
by 12z/Mon.

Grb watches/warnings/advisories...


Short term.....Eckberg
long term......rdm

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