Area Forecast Discussion
Issued by NWS Green Bay, WI

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000
FXUS63 KGRB 260828
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
328 AM CDT TUE APR 26 2016

FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 327 AM CDT TUE APR 26 2016

CLOUDS WILL BE SLOW TO CLEAR TODAY UNTIL JET ENERGY
UPSTREAM OVER MINNESOTA AT 09Z EXITS TOWARDS EVENING. LOW LEVEL
CONVERGENCE AND LEFT OVER MOISTURE WILL PRODUCE SCATTERED DRIZZLE
UNTIL AROUND14Z. CLOUDS...COLD ADVECTION AND NORTHEAST FLOW ACROSS
COLD WATERS OF THE LAKES AND BAY WILL RESULT IN HIGH TEMPERATURES
OF 8 TO 12 DEGREES BELOW NORMAL.

CLEARING EXPECTED FROM NORTH TO SOUTH TONIGHT AS UPPER RIDGING
ARRIVES FROM THE WEST. WOULD HAVE ISSUED A FROST ADVISORY FOR THE
AREA SOUTH OF A WAUSAU TO GREEN BAY LINE BUT THINK THAT THERE WILL
BE A BIT OF BREEZE OVERNIGHT AND THE AIR IS QUITE DRY. WILL
INCLUDE PATCHY FOG IN THE HAZARDOUS WEATHER OUTLOOK. LOWS TONIGHT
WILL BE ABOUT TEN DEGREES COLDER THAN NORMAL.

WEDNESDAY LOOKS TO BE SUNNY WITH TEMPERATURES JUST BELOW
NORMAL...THOUGH A NORTHEAST BREEZE WILL MAKE IT FEEL CHILLIER THAN
IT IS. CLOUDS WILL ARRIVE LATE IN THE DAY AS THE NEXT UPPER
SYSTEM APPROACHES FROM THE PLAINS.

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 327 AM CDT TUE APR 26 2016

A BLOCKY PATTERN IS EXPECTED TO HOLD THROUGH THE UPCOMING WEEKEND
AS AN UPPER RIDGE SITS OVER GREENLAND...A LARGE UPR LOW SPINS OVER
EASTERN CANADA AND ANOTHER MODEST UPPER RIDGE TO RESIDE OVER
CENTRAL CANADA. THIS PATTERN WILL SEND PACIFIC SYSTEMS SEWD INTO
THE SW CONUS...THEN E-NE INTO THE CENTRAL CONUS. THE MAIN PROBLEM
WILL BE TRYING TO DETERMINE THESE SYSTEM`S STRENGTH WHEN THEY
APPROACH WI AS THE MEAN FLOW IS CONFLUENT AND TENDS TO WEAKEN EACH
SYSTEM. TEMPERATURES ARE EXPECTED TO REMAIN BELOW NORMAL WITH
THURSDAY LOOKING LIKE THE COOLEST DAY OF THE EXTENDED PERIOD.

THE INITIAL SYSTEM OVER THE CENTRAL PLAINS/MIDWEST IS FORECAST TO
CONTINUE WEAKENING WEDNESDAY NIGHT DUE TO THE CONFLUENT FLOW OVER
THE CENTRAL CONUS. MOISTURE WILL STILL BE PREVALENT IN THE
VICINITY OF A NEARLY STATIONARY FRONT LOCATED WELL TO OUR SOUTH
(IA/MO BORDER THROUGH NORTH-CENTRAL IL) AND SOME OF THIS MOISTURE
IS EXPECTED TO MAKE A PUSH INTO WI. MEANWHILE...A LARGE AREA OF
HIGH PRESSURE IS FORECAST TO RESIDE OVER CENTRAL CANADA AND SEND
DRY AIR SOUTHWARD INTO WI ON E-NE WINDS. THEREFORE...THE BATTLE
WILL BE ON BETWEEN ADVANCING MOISTURE AND INFLUX OF DRY AIR. THE
NAM FAVORS THE DRIER AIR WINNING OUT WEDNESDAY NIGHT...WHILE THE
GFS FAVORS THE INCOMING MOISTURE. FOR NOW...BELIEVE NORTHERN WI
SHOULD REMAIN DRY...BUT WILL NEED TO CARRY A POP ESPECIALLY OVER
OUR SOUTHERN TIER OF COUNTIES. MIN TEMPERATURES TO RANGE FROM THE
UPPER 20S NEAR THE MI BORDER...TO THE MID TO UPPER 30S SOUTH.

THIS WEAKENING SYSTEM TO TRACK MAINLY TO THE EAST ON THURSDAY WITH
PRECIPITATION CHANCES CONTINUING OVER THE SOUTHERN 2/3RDS OF WI.
THE FAR NORTH SHOULD REMAIN DRY WITH A BIT OF SUNSHINE AND THIS
WOULD FLIP THE SCRIPT WITH WARMER TEMPERATURES NORTH/COOLER SOUTH.
LOOK FOR MAX TEMPERATURES IN THE MID TO UPPER 40S LAKESIDE...UPPER
40S TO AROUND 50 DEGREES SOUTH AND LOWER TO MIDDLE 50S FAR NORTH.

THE SOUTHERN FRINGE OF THE EXPANSIVE CANADIAN SURFACE HIGH IS
FORECAST TO BUILD SOUTHWARD INTO THE GREAT LAKES THURSDAY NIGHT
AND BRING AT LEAST SOME DECREASE IN CLOUDS TO CENTRAL/EAST-CENTRAL
WI. THE AMOUNT OF CLEARING WILL BE KEY AS TO HOW COOL WE CAN GET
SINCE SURFACE WINDS WILL BE RELATIVELY LIGHT AND THE AIR MASS
ALOFT IS COLD (8H TEMPERATURES FROM 0C TO +2C)...THUS FROST IS
POSSIBLE WHERE THE GROWING SEASON HAS TECHNICALLY STARTED. MIN
TEMPERATURES ARE EXPECTED TO BE IN THE LOWER 30S NORTH...MID TO
UPPER 30S SOUTH. MOSTLY SUNNY TO PARTLY CLOUDY SKIES ARE FORECAST
ACROSS THE REGION ON FRIDAY WITH THE CANADIAN HIGH PRESSURE FIRMLY
IN CONTROL OF OUR WEATHER. A PERSISTENT E-NE WIND FLOW WILL
CONTINUE TO KEEP TEMPERATURES COOL OVER EASTERN WI...WHILE CENTRAL
WI TO ONLY BE A FEW DEGREES BELOW NORMAL. THIS TRANSLATES TO MAX
TEMPERATURES IN THE LOWER 50S NEAR LAKE MI...MID 50S EAST-CENTRAL
WI AND UPPER 50S TO AROUND 60 DEGREES ELSEWHERE.

AFTER ANOTHER QUIET AND COOL FRIDAY NIGHT...ATTENTION TURNS TO THE
NEXT PACIFIC SYSTEM THAT IS PROGGED TO BE SITUATED OVER THE
CENTRAL PLAINS ON SATURDAY. MUCH LIKE ITS PREDECESSOR...THIS
SYSTEM WILL PULL GULF MOISTURE NORTHWARD WITH A WAVY FRONTAL
BOUNDARY EXTENDED FROM THE CENTRAL PLAINS EASTWARD TO THE OHIO
RIVER VALLEY. EXPECT TO SEE CLOUDS INCREASE OVER NE WI ON SATURDAY
AND THEN WE WILL SEE THE SAME BATTLE OF INCOMING MOISTURE VERSUS
DRY E-NE AIR THAT THE AREA SAW WEDNESDAY NIGHT. THE GFS AND GEM
HOLD ENOUGH DRY AIR IN PLACE TO KEEP SATURDAY COMPLETELY DRY...
HOWEVER THE ECMWF IS MORE AGGRESSIVE WITH THE MOISTURE TRANPORT
AND BRINGS PRECIPITATION INTO ALL BUT FAR NE WI ON SATURDAY. TOO
MUCH UNCERTAINTY YET TO DROP ANY POPS...THUS HAVE MAINTAINED LOW
CHC POPS MAINLY SOUTH OF A RHI-SUE LINE. MAX TEMPERATURES LOOK TO
BE SIMILAR TO FRIDAY.

UNFORTUNATELY...THE NEW 00Z MODEL OUTPUT DOES LITTLE TO CLEAR UP
THE POTENTIAL PRECIPITATION CHANCES EARLY NEXT WEEK WITH THE GFS
HOLDING THE VAST MAJORITY OF RAIN SHOWERS TO OUR SOUTH SUNDAY AND
MONDAY...TAKING A TRACK SIMILAR TO THE FIRST SYSTEM. THE GEM IS A
BIT FARTHER NORTH AND KEEPS THE NORTH DRY. THE ECMWF IS THE
WETTEST MODEL AND MAINTAINS A WEAK SURFACE LOW INTO THE WESTERN
GREAT LAKES...WITH RAIN SHOWERS MOVING INTO THE FORECAST AREA
SUNDAY AFTERNOON AND PERSISTING THROUGH MONDAY. AT THIS POINT...
ANY OF THESE SOLUTIONS ARE PLAUSIBLE SO HAVE FOLLOWED THE
CONSENSUS SOLUTION WHICH KEEPS A SLIGHT CHANCE POP NORTH...CHANCE
POPS SOUTH FOR BOTH SUNDAY AND MONDAY. TEMPERATURES WILL CONTINUE
TO RUN A COUPLE OF DEGREES BELOW NORMAL INTO EARLY NEXT WEEK.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1019 PM CDT MON APR 25 2016

EXPECT PLENTY OF LOW-LEVEL MOISTURE TO LINGER TNGT...RESULTING IN
IFR/LIFR CIGS. THERE SHOULD BE SOME IMPROVEMENT TOMORROW AS DRIER
AIR WORKS INTO THE AREA FM THE NE. THE MAIN QUESTION IS HOW
QUICKLY THE IMPROVEMENT WL OCCUR. PLAN TO STAY PRETTY CLOSE TO A
CONSENSUS OF THE GUIDANCE PRODUCTS...WHICH INDICATE POOR
CONDITIONS LINGERING INTO THE DAY FOLLOWED BY SIGNIFICANT
IMPROVEMENT IN THE AFTN.
&&

.MARINE...
ISSUED AT 327 AM CDT TUE APR 26 2016

GUSTY NORTHEAST WINDS AND LARGE WAVES WILL CONTINUE TO
PRODUCE HAZARDOUS CONDITIONS FOR SMALL CRAFT INTO THE AFTERNOON.
&&

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

$$

SHORT TERM.....RDM
LONG TERM......AK
AVIATION.......SKOWRONSKI
MARINE.........RDM



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