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Area forecast discussion 
National Weather Service Green Bay WI
657 PM CDT sun Jul 27 2014

Updated aviation portion for 00z taf issuance

issued at 235 PM CDT sun Jul 27 2014

Cooler and less humid for the upcoming work week.

Major amplification of the lngwv pattern is underway. Upper troughs
will settle in off the British Columbia coast and over the lower
Great Lakes region...while an upper ridge strengthens over the
intermountain west. This is going to be a very stable pattern...
with the main features remaining in place throughout the forecast
period. About the only significant change that will occur will be a
gradual weakening of the flow across the Continental U.S. As the cold air
within the upper troughs slowly modifies.

The northwest upper flow regime will keep temperatures at least a little below
normal for the period. There will be ample opportunities for
precipitation as disturbances ride southeastward across the area and into the
eastern Great Lakes upper trough. But the Main Pool of very moist unstable
air will remain well to our with moisture limited...precipitation
amnts will be modest.

Short term...tonight and Monday
issued at 235 PM CDT sun Jul 27 2014

The latest rap analysis and satellite/radar imagery show a potent
upper level low diving southeast across northeast Wisconsin early
this afternoon. Showers and thunderstorms have been most widespread
so far to day over north-central and northeast Wisconsin where pea
sized hail was reported around midday over northern Oconto and
Marinette...but no reports of any severe weather. Just behind the upper
low...a cold front is dropping south over northern Wisconsin and the
back edge of the cloud line is making steady progress southward over
Central Lake Superior. As the upper low exits...the main forecast
concerns revolve around timing the end of the precipitation and followed by

Tonight...upper level low pressure will be moving southeast over
Southern Lower Michigan. Behind the low...prognosticated soundings show
increasing subsidence as evident by middle-level drying and a cap
building at around 750mb through the evening. But left a chance of
showers over east-central and northeast Wisconsin through about
middle-evening as middle and low levels still look relatively moist
through this time. As this is occurring...a back door cold front
will be dropping south over central Wisconsin where clearing skies
should occur behind its passage. This clearing will work into far
northern Wisconsin late this afternoon and east-central Wisconsin last
by late in the evening. Brisk north winds will put a chill in the
air behind the front as temperatures fall into the middle 40s north
to middle 50s south.

Monday...high pressure will be nosing into the area which will make
for a quiet and seasonably cool middle-Summers day. Should see diurnal
cumulus pop again by late in the morning only to be capped off at around
750-700mb. Highs in the lower to middle 70s.

Long term...Monday night through Sunday
issued at 235 PM CDT sun Jul 27 2014

Tough to add much resolution to the forecast beyond the diurnal trend
for more clouds and rain showers during the afternoon/early evening...and a min
in the clouds and precipitation chances late at night and into the morning.
Stayed close to broad based blend of guidance products

Aviation...for 00z taf issuance
issued at 649 PM CDT sun Jul 27 2014

Scattered showers continue over southern half of WI...though
thunder has ended as more stable air mass working in. Clearing
moving through the north...though clouds moving off Lake Superior
holding together as they move into the u p. Ceilings with these clouds
VFR. Will monitor tafs to add if they stay together as move into
northern WI. North winds expected to remain breezy through the
evening. Should see good flying weather tomorrow with VFR diurnal
cumulus building by late morning. &&

Grb watches/warnings/advisories...


short term.....Mpc
long term......skowronski

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