000
FXUS63 KGRB 191155
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
655 AM CDT SAT APR 19 2014

UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 341 AM CDT SAT APR 19 2014

PCPN TRENDS AND TEMPERATURES WILL BE THE MAIN FCST CONCERNS.

MODELS HAVE SLOWED DOWN THE PROGRESSION OF THE PCPN ASSOCIATED
WITH A WEAK FRONTAL BOUNDARY TODAY AND TONIGHT. RAINFALL SHOULD BE
CONFINED TO OUR FAR NW COUNTIES TODAY...WHERE A 40-50 KT LLJ AND
SOME UPPER LEVEL DIVG WILL BE FOCUSED. THE PCPN WILL GRADUALLY
SHIFT SOUTHEAST TONIGHT...WITH THE HIGHEST POPS OVER FAR NE
WI...WHERE THE LLJ AND UPPER LEVEL DIVG WILL TAKE AIM. THE BEST
PCPN CHANCES WILL BE FOUND OVER C/EC WI ON SUNDAY...WITH RAINFALL
TAPERING OFF OVER OVER NORTHERN WI. HAVE OPTED TO LEAVE THUNDER
OUT OF THE FCST THROUGH THE PERIOD...AS INSTABILITY IS VERY
MARGINAL. HAVE ADDED SOME PATCHY FOG OVER NC/FAR NE WI LATE
TONIGHT INTO EARLY SUNDAY...AS LOW-LEVEL MOISTURE INCREASES OVER
THE DEEP SNOW PACK.

USED A BLEND OF THE BETTER PERFORMING GUIDANCE SETS FOR MAX/MIN
TEMPS THE NEXT COUPLE DAYS. EXPECT A LARGE TEMPERATURE GRADIENT
TODAY...WITH HIGHS RANGING FROM THE MID TO UPPER 40S OVER THE
SNOW COVERED NORTHWOODS TO THE LOWER TO MIDDLE 60S IN CENTRAL WI.
MILDER MIN TEMPS IN THE 40S ARE EXPECTED TONIGHT...WITH HIGHS IN
THE UPPER 50S TO MIDDLE 60S ON EASTER SUNDAY.

.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 341 AM CDT SAT APR 19 2014

THE MEDIUM RANGE MODELS REMAIN IN VERY GOOD AGREEMENT WITH THE LARGE
SCALE FEATURES ACROSS NORTH AMERICA DURING THIS PORTION OF THE
FORECAST.  BY THE END OF THE PERIOD...THE ECMWF IS A LITTLE QUICKER
SHIFTING A CLOSED CYCLONE ACROSS THE REGION.  SINCE THE GFS ENSEMBLE
MEAN IS BETWEEN BOTH MODELS WITH THIS SYSTEM...A GENERAL MODEL
COMPROMISE SHOULD SUFFICE.

SUNDAY NIGHT THROUGH MONDAY NIGHT...STILL A QUESTION MARK WHERE A
WEAK COOL FRONT WILL STALL OUT BY THE START OF SUNDAY NIGHT.  THE
INHERITED FORECAST DEPICTS A BOUNDARY RUNNING FROM WEST-CENTRAL TO
NORTHEAST WISCONSIN AND THE LATEST DATA DOES NOT SUPPORT STRAYING
FROM THIS SCENARIO.  AS A RESULT...FOCUS OF PRECIP WILL OCCUR ALONG
THE FRONT OVER CENTRAL TO NORTHEAST WISCONSIN.  AN UPTICK OF
INTENSITY/COVERAGE IS POSSIBLE SUNDAY NIGHT THANKS TO INCOMING
MID-LEVEL HEIGHT FALLS AHEAD OF SEPARATE PIECES OF SHORTWAVE ENERGY
MOVING ACROSS THE PLAINS.  WILL CONTINUE TO SHOW LIKELY POPS IN THAT
CORRIDOR.  THE STRONGEST PIECE OF ENERGY IN THE NORTHERN STREAM
ARRIVES ON MONDAY AND SHOULD GIVE THE FRONT A GENTLE NUDGE TO THE
EAST OVER THE COURSE OF THE DAY.  STILL THOUGH...THE SOUTHEAST HALF
OF THE FORECAST AREA WILL LIKELY SEE WET WEATHER CONTINUE THROUGH
MUCH OF THE DAY.  THINK MOST OF THE PRECIP WILL HAVE EXITED THE
REGION EXCEPT FOR POSSIBLY THE LAKE SHORE AT THE START OF MONDAY
EVENING.  COLD ADVECTION WILL OCCUR BEHIND THE FRONT...WHICH COULD
LEAD TO A STRATUS DECK DROPPING SOUTHEAST ACROSS THE FORECAST AREA.
WILL SIDE MORE PESSIMISTIC WITH CLOUD COVER.  NO SIGNIFICANT CHANGES
TO TEMPS.

REST OF THE FORECAST...AFTER SOME MORNING CLOUDS ON TUESDAY...SHOULD
SEE INCREASING SUNSHINE AS HIGH PRESSURE MOVES INTO THE REGION.
THIS HIGH PRESSURE WILL HANG AROUND THROUGH WEDNESDAY...WHICH IS NOW
LOOKING LIKE A BETTER CHANCE OF BEING DRY THROUGH THE DAY.  AS A
LARGE WESTERN CONUS TROUGH MOVES INTO THE PLAINS...CHANCES OF PRECIP
WILL INCREASE WEDNESDAY NIGHT.  THE WETTEST PERIOD LOOKS TO BE
THURSDAY INTO THURSDAY NIGHT WHEN SOME THUNDERSTORMS ARE POSSIBLE.
TURNING COOLER AND CONTINUED UNSETTLED ON FRIDAY.
&&

.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 650 AM CDT SAT APR 19 2014

EXPECT VFR CONDITIONS TODAY...WITH ONLY SOME LIGHT RAIN REACHING
NC WI DURING THE AFTERNOON. THE RAIN IS EXPECTED TO SPREAD SOUTHEAST
ACROSS THE REST OF THE FCST AREA TONIGHT...WITH CIGS GRADUALLY DROPPING
TO MVFR...AND THE POTENTIAL FOR SOME IFR CONDITIONS IN FOG OVER THE
SNOW COVERED REGIONS OF NORTHERN WI.

LLWS WILL BE A CONCERN FOR THE WESTERN TAF SITES EARLY THIS MORNING...
THEN OVER THE ENTIRE FORECAST AREA TONIGHT.
&&

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

$$

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