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000
FXUS63 KGRB 150319
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1019 PM CDT FRI MAR 14 2014

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 226 PM CDT FRI MAR 14 2014

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A COMPACT
SHORTWAVE MOVING TO THE EAST OVER NORTHEAST WISCONSIN EARLY THIS
AFTERNOON.  PRECIP REPORTS ACROSS THE REGION HAVE BEEN FAR AND FEW
BETWEEN SO FAR TODAY...WITH ONLY SOME SITES IN VILAS COUNTY AND MTW
REPORTING ANY PRECIP.  SUSPECT SOME PRECIP REACHED THE GROUND OVER
FAR NE WISCONSIN TOO BASED ON RADAR RETURNS.  12Z SOUNDINGS THIS MORNING
SHOWED A DRY WEDGE BELOW 700MB...AND SUSPECT THIS DRY AIR IS
PREVENTING MID-LEVEL RETURNS FROM REACHING THE GROUND AT MOST
LOCATIONS.  NOT MANY REPORTS OF SNOW UPSTREAM EITHER...ONLY A FEW
OVER NORTHERN MINNESOTA.  SLIGHT COLD ADVECTION IS OCCURRING BEHIND
A COOL FRONT...WHICH IS MOVING ACROSS LAKE MICHIGAN.  THE COMBO OF
CLOUDS AND COLDER AIR HAS HALTED THE HEATING CURVE OVER
NORTH-CENTRAL WISCONSIN.  MEANWHILE...AN ARCTIC COLD FRONT IS
DROPPING SOUTHEAST OVER NORTHEAST MINNESOTA.  FORECAST CONCERNS
INCLUDE PRECIP CHANCES AND CLOUDS/TEMPS.

TONIGHT...BEHIND A COMPACT SHORTWAVE AND ASSOCIATED SURFACE LOW...AN
ARCTIC COLD FRONT WILL BE SHIFTING SOUTHEAST ACROSS THE FORECAST
AREA DURING THE EVENING.  MID-LEVEL MOISTURE AND UPPER FORCING WILL
HAVE DEPARTED BY THIS TIME...BUT FLOW WILL BE TURNING TO THE NNW OFF
LAKE SUPERIOR AND A SURFACE TROUGH WILL BE HANGING BACK OVER FAR
NORTHERN WISCONSIN.  WILL HAVE TO KEEP A CHANCE OF SNOW SHOWERS
ACROSS THE NORTH BECAUSE OF THIS...BUT LACK OF PRECIP ON UPSTREAM
OBS SUPPORTS BACKING OFF ON PRECIP AMOUNTS AND POPS SOMEWHAT.  WILL
ONLY SHOW A COUPLE TENTHS OF AN INCH OF ACCUMULATIONS OVER NORTHERN
VILAS COUNTY.  FORECAST SOUNDINGS DRY OUT AFTER MIDNIGHT AND THINK
CLOUDS AND SNOW SHOWERS WILL RETREAT TO THE NORTH.  MODELS APPEAR A
LITTLE TOO QUICK THOUGH SINCE COLD ADVECTION WILL BE ONGOING...SO
WILL NOT SHOW CLEARING SKIES OVER CENTRAL AND EAST-CENTRAL WISCONSIN
UNTIL LATE TONIGHT.  WITH THE CLOUDS AND PERSISTENT NORTHWEST
WINDS...SIDED WITH THE WARMER GUIDANCE WHICH SHOWS TEMPS RANGING
FROM THE MID-TEENS NORTH TO MID 20S SOUTH.

SATURDAY...THE ARCTIC FRONT WILL STALL FROM THE NORTHERN PLAINS TO
THE SOUTHERN GREAT LAKES SATURDAY MORNING.  DIGGING SHORTWAVE OVER
THE PLAINS AND RIGHT REAR QUAD OF THE JET WILL CREATE THE FORCING
FOR A BAND OF SNOW TO DEVELOP ALONG THE FRONT WHICH PUSHES INTO
SOUTHERN WISCONSIN DURING THE AFTERNOON.  THE NAM IS THE ONLY MODEL
WHICH TRACKS THE BAND OF SNOW INTO CENTRAL WISCONSIN. THE REST OF
THE MODELS ARE FARTHER SOUTH OVER SOUTHERN WISCONSIN.  WILL SIDE
WITH THE MAJORITY OF GUIDANCE.  STILL PLENTY OF LOW LEVEL MOISTURE
LEFT OVER ON PROGGED SOUNDINGS...WHICH TURNS INTO A CU FIELD WITH
DAYTIME HEATING.  SO THINKING ANY CLEARING EARLY SATURDAY MORNING
WILL PARTIALLY FILL BACK IN BY LATE IN THE MORNING OR EARLY IN THE
AFTERNOON.  ADDITIONALLY...LOW LEVEL FLOW WILL BE TURNING TO THE
NORTHEAST OVER NORTHERN LAKE MICHIGAN...WHICH COULD GENERATE A FEW
FLURRIES OVER EAST-CENTRAL WISCONSIN.  WILL HAVE A MENTION LATE IN
THE AFTERNOON.  NO SIGNIFICANT CHANGES TO TEMPS.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 226 PM CDT FRI MAR 14 2014

CANADIAN HIGH PRESSURE WILL DOMINATE THE WEATHER PATTERN SATURDAY
NIGHT THROUGH SUNDAY NIGHT. THIS WILL BRING VERY COLD CONDITIONS
FOR MID MARCH WITH LOWS IN THE SINGLE DIGITS ABOVE AND BELOW
ZERO SATURDAY NIGHT...AND HIGHS MAINLY IN THE 20S ON SUNDAY.
THE HIGH WILL SLIDE EAST OF THE AREA SUNDAY NIGHT AS SYSTEM
APPROACHES FROM THE WEST AND 850MB WARM ADVECTION BEGINS IN EARNEST.

THE TUESDAY THROUGH WEDNESDAY HAS BECOME MORE COMPLICATED THIS MORNING
AS THE ECMWF IS MUCH SLOWER AND WARMER THAN THE GFS/CANADIAN. THE
CANADIAN MODEL IS THE COLDEST SOLUTION WHILE THE THE GFS IS IN THE
MIDDLE. SIGNIFICANT DIFFERENCES IN THE TRACK OF THE SYSTEM IS ALSO
NOTED. THE GFS ENSEMBLE MEMBERS DID SHOW A LARGE VARIABLE IN THE
POSSIBLE TRACK OF THE STORM. WOULD LIKE TO LEAN TOWARD THE ECMWF
MODEL FOR THIS PACKAGE DUE TO ITS BETTER PERFORMANCE IN THE LATER
PERIODS...BUT THIS MODEL IS CONSIDERABLY WARMER AND SLOW THAN
PREVIOUS RUN. WILL CONTINUE WITH PREVIOUS FORECAST PACKAGE SINCE
THERE ARE SEVERAL MORE DAYS UNTIL THE EVENT AND LATER MODELS CAN
CONVERGE ON A SIMILAR SOLUTION.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1016 PM CDT FRI MAR 14 2014

CLOUD DECK HAS FILLED BACK IN ACRS THE AREA. MOSTLY VFR CIGS IN
C/NE/E-C WI...AND MVFR CIGS IN N-C WI. THE LOWER CIGS WL SAG SWD
SOME OVERNIGHT. EXPECT SOME BREAKS IN THE OVC TO DEVELOP IN THE
FAVORED REGION ACRS ERN WI BY MORNING. BUT WILL PROBABLY GET AN
UPTICK IN CLDS AGAIN TOMORROW MORNING.
&&

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

$$

SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......SKOWRONSKI