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000
FXUS63 KGRB 301144
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
544 AM CST SAT NOV 30 2013

UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 324 AM CST SAT NOV 30 2013

MINOR PCPN CHANCES AND TEMPERATURES ARE THE MAIN FCST CONCERNS.

WAA WAS ONGOING OVER WISCONSIN AHEAD OF A COLD FRONT ADVANCING
THROUGH THE NORTHERN PLAINS. WIDESPREAD CLOUD COVER HAD DEVELOPED
OVER GRB CWA...BUT PCPN WAS ONLY OCCURRING WELL TO OUR NORTH...
OVER THE MN ARROWHEAD AND THE NORTHERN UPPER PENINSULA. ALTHOUGH
THE CHANCE OF FZDZ HAS NOT BEEN REMOVED FROM THE MORNING FCST IN
NORTHERN WI...THE FACT THAT CLOUD CEILINGS ARE STILL ABOVE 3000 FT
AND SFC DEW POINT DEPRESSIONS ARE 7-8 DEGREES F...MAKES IT LOOK
LIKE A LONGSHOT. THE COLD FRONT WILL MOVE THROUGH THE FORECAST
AREA DURING THE AFTERNOON...AND MAY GENERATE SOME FLURRIES OR
MIXED SPRINKLES/FLURRIES...WHICH SHOULD EXIT EASTERN WI BY EARLY
EVG. TEMPS HAVE BEEN STEADY OR SLOWLY RISING OVERNIGHT...AND
ARE EXPECTED TO CLIMB TO A FEW DEGREES ABOVE NORMAL THIS
AFTERNOON.

EXPECT PARTIAL CLEARING TO OCCUR TONIGHT...IN THE WAKE OF THE
FRONTAL PASSAGE. WEAK N-NE FLOW OFF LAKE SUPERIOR SHOULD BRING
LOW CLOUDS AND PERHAPS SOME LIGHT PCPN INTO VILAS COUNTY
OVERNIGHT. FZDZ SHOULD BE THE DOMINANT PCPN TYPE DURING THE EVG
AND VERY EARLY MORNING HOURS...WITH LIGHT SNOW SHOWERS OR
FLURRIES EXPECTED LATE AS TEMPS IN THE SATURATED LAYER FINALLY
DROP TO -10 C. MIN TEMPS SHOULD FALL INTO THE UPPER TEENS OR
LOWER 20S AT MOST LOCATIONS.

WEAK HIGH PRESSURE WILL BRING PARTLY TO MOSTLY CLOUDY AND DRY
CONDITIONS ON SUNDAY...WITH HIGHS EXPECTED TO BE SLIGHTLY COOLER...
IN THE UPPER 20S TO MIDDLE 30S.

.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 324 AM CST SAT NOV 30 2013

MEDIUM RANGE MODELS ARE GETTING THE HANG OF THE UPPER AIR PATTERN
FOR NEXT WEEK.  SHARP RIDGING OVER THE EASTERN PACIFIC AND INTO
ALASKA WILL LEAD TO A DEEP TROUGH DIGGING ACROSS THE WESTERN CONUS
WHICH WILL GRADUALLY SHIFT EAST TO THE GREAT LAKES TOWARDS THE END
OF THE NEXT WORK WEEK.  HOWEVER...SMALLER SCALE IMPULSES ARE HAVING
PROFOUND IMPACTS ON DETAILS OF SURFACE FEATURES...MAKING IT
DIFFICULT TO GET A HANDLE ON THE SENSIBLE WEATHER.  USUALLY WHEN THE
PATTERN AMPLIFIES LIKE THIS...SLOWER IS BETTER...SO WILL SIDE WITH
THE SLOWER EVOLVING SOLUTION WHICH IS MORE LIKE THE ECMWF.
CONFIDENCE IS QUITE LOW HOWEVER...SO WILL NOT DEVIATE MUCH FROM THE
ALLBLEND FOR LATER PERIODS.

SUNDAY NIGHT THROUGH MONDAY NIGHT...WEAK SHORTWAVE WILL BE MOVING
ACROSS THE AREA SUNDAY NIGHT AND MONDAY.  HIGH CLOUDS WILL BE ON THE
INCREASE SUNDAY NIGHT...AND THERE MAY BE LOW CLOUDS STICKING AROUND
BENEATH THE INVERSION.  BUT PROGGED SOUNDINGS INDICATE A SIGNIFICANT
DRY WEDGE IN THE MID-LEVELS THAT WOULD MAKE IT HARD TO GENERATE ANY
PRECIP.  LIGHT ONSHORE FLOW OFF LAKE MICHIGAN MAY LEAD TO A FEW
FLURRIES ALONG THE LAKE SHORE...BUT CHANCES OF MORE SIGNIFICANT
PRECIP PUSHING IN FROM THE WEST LOOKS TO HAVE DIMINISHED.  THOUGH
SHORTWAVE TROUGHING WILL STILL BE MOVING OVERHEAD ON MONDAY...WILL
STILL BE DEALING WITH THE DRY WEDGE IN THE MID-LEVELS...AND ANY
CHANCES OF PRECIP ARE MORE LIKELY TO OCCUR CLOSER TO A DEVELOPING
BAROCLINIC ZONE OVER THE NORTHERN MISSISSIPPI VALLEY.  WILL SCALE
BACK POPS ACROSS THE FORECAST AREA.  THE GFS QUICKLY MOVES THE
BAROCLINIC ZONE EAST INTO THE REGION MONDAY NIGHT WHILE THE
ECMWF/GEM KEEP IT TO THE SOUTHWEST.  THE LATTER MAKES SENSE GIVEN
THE AMPLIFYING PATTERN SO WILL TRIM BACK PRECIP CHANCES AGAIN.  THE
EASTERLY FLOW WILL KEEP A CHANCE OF FLURRIES GOING FOR THE LAKE
MICHIGAN SHORELINE THOUGH.

REST OF THE FORECAST...THE PREVIOUS SHIFT REMOVED PRECIP CHANCES ON
TUESDAY...WHICH STILL LOOKS REASONABLE AS THE PATTERN CONTINUES TO
REORGANIZE.  NO END TO THE EASTERLY FLOW HOWEVER...WHICH SHOULD KEEP
CONDITIONS RATHER CLOUDY AND UNSETTLED ALONG THE LAKE MICHIGAN
SHORELINE.  PRECIP CHANCES BEGIN TO IMPROVE TUESDAY NIGHT AND MORE
SO WEDNESDAY THROUGH THURSDAY WHEN LOW PRESSURE TRAVERSES SOMEWHERE
AROUND THE REGION.  TOO HARD TO GET INTO SPECIFICS YET...WHICH
OBVIOUSLY WOULD IMPACT PRECIP TYPE AND SNOW ACCUMULATION POTENTIAL.
ARCTIC AIR WILL FLOOD THE REGION BEHIND THE SYSTEM BY THE END OF THE
WEEK.
&&

.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 538 AM CST SAT NOV 30 2013

CLDS WITH BASES IN THE 4K-7K FT RANGE COVERED THE FORECAST AREA
EARLY THIS MORNING. BASED ON LATEST TRENDS IT APPEARS THAT FZDZ
WILL NOT FORM OVER NORTHERN WI AS WAS PREVIOUSLY ANTICIPATED.
A COLD FRONT MAY BRING A FEW FLURRIES OR MIXED SPRINKLES/FLURRIES
AS IT MOVES THROUGH THIS AFTERNOON/EARLY EVG. SOME MVFR CIGS
SHOULD PUSH DOWN INTO THE REGION AFTER THE FRONT MOVES THROUGH.
LIGHT NORTH FLOW OFF LAKE SUPERIOR MAY LEAD TO LOCAL IFR CIGS AND
PERHAPS SOME PATCHY FZDZ/FLURRIES OVER FAR NC WI TONIGHT.

LLWS IS EXPECTED TO WEAKEN AT THE TAF SITES THIS MORNING.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM.....KIECKBUSCH
LONG TERM......MPC
AVIATION.......KIECKBUSCH