000
FXUS63 KGRB 122350
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
650 PM CDT WED JUN 12 2013

ADDED UPDATE SECTION AND NEW AVIATION PORTION FOR 00Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND THURSDAY
ISSUED AT 645 PM CDT WED JUN 12 2013

FCST AREA GETTING CLIPPED BY NRN PORTION OF DEVELOPING MCS. RAISED
POPS ACRS THE SRN 1/3 OF THE AREA TO ACCOUNT FOR PCPN EARLY THIS
EVENING...BUT PCPN SHOULD BE EXITING TO THE SE DURING THE NEXT FEW
HRS. THEN QUIET WX EXPECTED AS HIGH PRESSURE BUILDS INTO THE RGN.
&&

.SHORT TERM...TONIGHT AND THURSDAY
ISSUED AT 229 PM CDT WED JUN 12 2013

NRN EXTENT OF TSTMS LATE THIS AFTERNOON/EARLY THIS EVENING CONTS
TO BE THE MAIN FOCUS IN THE SHORT-TERM.

THE 19Z MSAS SFC ANALYSIS SHOWED A PAIR OF LOW PRES AREAS OVER
CNTRL IA AND NE IL. A WRMFNT CONNECTED THESE LOW PRES SYSTEMS AND
THEN CONTINUED EWD TO LK ERIE. A CDFNT EXTENDED SWWD FROM THE IA
LOW THRU THE CNTRL PLAINS. LATEST RADAR MOSAIC INDICATED A BAND OF
LIGHT SHWRS MOVING THRU PARTS OF N-CNTRL AND FAR NE WI. THE MAIN
SHOW WAS JUST DEVELOPING OVER NE IA AND IS EXPECTED TO RAPIDLY
INCREASE IN COVERAGE AND INTENSITY.

INITIALLY...WE WL HAVE TO DEAL WITH THE PESKY FRONTOGENETICALLY
FORCED BAND OF SHWRS OVER PARTS OF THE FCST AREA. EXPECT THIS PCPN
TO GRADUALLY DISSIPATE AS BETTER FORCING SHIFTS SOUTH AND AIR MASS
OVER N-CNTRL WI IS RELATIVELY DRY WITH DEW PTS IN THE 40S. A
STRONG SHORTWAVE TROF WL CONT TO DIG SE THRU THE UPR MS VALLEY AND
LATE THIS AFTERNOON AND EVENTUALLY THRU THE SRN GREAT LAKES THIS
EVENING. MEANWHILE...THE SFC LOW IS FCST TO TRACK ACROSS NRN
SECTIONS OF ILLINOIS AND INDIANA WITH THE WRMFNT EXTENDED EWD FROM
THE SFC LOW. STRONG INSTABILITY TO RESIDE ALONG AND SOUTH OF THIS
FRONTAL BOUNDARY AND EXPECT STRONG TO SEVERE TSTMS TO DEVELOP TO
OUR W-SW (ERN IA/NW IL) WITH AN EVENTUAL MOVEMENT TO THE E-SE.
CANNOT RULE OUT AT LEAST SCT SHWRS/TSTMS OVER SRN SECTIONS OF THE
FCST AREA ROUGHLY SOUTH OF A LINE FROM MOSINEE TO SHAWANO TO
KEWAUNEE. ONCE THE SFC LOW/SHORTWAVE TROF DEPART THE REGION LATER
THIS EVENING...A MORE TRANQUIL WEATHER PATTERN TO TAKE OVER AS HI
PRES BEGINS TO BUILD SOUTH OF CANADA. CLEARING SKIES AND AN INFLUX
OF COOLER AIR WL ALLOW TEMPS TO DROP INTO THE UPR 40S TO AROUND 50
NORTH...MID 50S CNTRL/E-CNTRL WI.

THIS AREA OF HI PRES TO BUILD ACROSS WI ON THU AND PROVIDE FOR A
MOSTLY SUNNY DAY WITH FAIR WEATHER CUMULUS CLOUDS DEVELOPING WITH
DAYTIME HEATING. A NORTHERLY WIND WL KEEP TEMPS IN CHECK WITH 8H
TEMPS ONLY AROUND +10C. THIS WOULD ALLOW READINGS TO REACH THE
LOWER 70S NORTH...MIDDLE 70S CNTRL/E-CNTRL WI.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 229 PM CDT WED JUN 12 2013

FLUID PATTERN THIS PERIOD AS UPPER LOW LIFTS NORTH AND EAST OUT
OF WEST COAST TROUGH...LEADING TO A ZONAL FLOW PATTERN SETTING UP
OVER THE AREA FOR THE UPCOMING WEEKEND. RIDGE AGAIN BUILDS OVER
THE PLAINS FOR DRY PERIOD FOR MUCH OF THE NEXT WORK WEEK.

MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT DIFFERING DURING THE
WEEKEND SOME WITH SPEED AND STRENGTH OF SHORT WAVE FEATURES. HAVE
TRENDED TOWARDS GFS/EC BLEND FOR THIS FORECAST.

CANADIAN HIGH PRESSURE WILL MOVE ACROSS THE REGION THURSDAY NIGHT
AND FRIDAY. DRY AIRMASS EXPECTED TO MOVE INTO THE REGION ON NORTH
WINDS WITH DEWS OVERNIGHT DROPPING INTO UPPER 30S TO LOW
40S. LOOKING AT A SEASONABLY COOL NIGHT. ON FRIDAY NIGHT WARM
ADVECTION TO GET GOING AHEAD OF LOW NOW OVER ALBERTA. CONVECTIVE
COMPLEX POSSIBLE WITH MODELS SUGGESTING MAINLY OVER SW WI...WHERE
LL JET IS FOCUSED.

CHANCES OF TSTMS EXPECTED THROUGH THE WEEKEND...WITH INCREASING
INSTABILITY...MOVEMENT OF COLD FRONT INTO/THROUGH CWA...LESSENING
ON SUNDAY AS MOISTURE/INSTABILITY MORE TIED TO FRONT TO SOUTH OF
THE AREA.

REST OF THE FORECAST DRY AT THIS TIME AS HIGH PRESSURE BUILDS IN.
&&

.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 645 PM CDT WED JUN 12 2013

CARRIED TSRA FOR THE START OF THE TAF PERIOD ACRS ALL BUT N-C WI.
BUT WITH DEVELOPING MCS SHIFTG OFF TO THE SE...PCPN SHOULD END
FAIRLY QUICKLY. DECENT SFC PRESSURE GRADIENT ON N SIDE OF FRONTAL
WAVE SHOULD MITIGATE FOG POTENTIAL TNGT...SO JUST HAVE VFR
CONDITIONS ONCE CONVECTION PULLS OFF TO THE SE.
&&

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

$$

UPDATE.........SKOWRONSKI
SHORT TERM.....KALLAS
LONG TERM......TE
AVIATION.......SKOWRONSKI