Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 220950
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
450 AM CDT FRI AUG 22 2014

FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SYNOPSIS...
ISSUED AT 442 AM CDT FRI AUG 22 2014

WARM AND HUMID THE NEXT SEVERAL DAYS.

AMPLIFICATION OF THE UPPER PATTERN ACRS NOAM CONTG AS SHRTWV
DIGGING DOWN THE WEST COAST WAS DEEPENING THE WRN TROF AND PULLING
IT BACK WWD A BIT. DOWNSTREAM...RIDGING BUILDING NNEWD FM THE
LOWER MISSISSIPPI VALLEY WL EVENTUALLY LINK WITH BLOCKY RIDGE OVER
NWRN QUEBEC. THESE CHGS WL RESULT IN THE FCST AREA BEING UNDER THE
RIDGE AXIS THE NEXT COUPLE DAYS...THEN SHRTWV EJECTING OUT OF THE
WRN TROF WL SHOVE THE NRN PORTION OF THE RIDGE EWD...LEAVING SW
UPR FLOW ACRS THE FCST AREA FOR EARLY NEXT WEEK. THE UPR FLOW WL
BECOME MORE PROGRESSIVE AND RAPIDLY LOSE AMPLITUDE AFTER THAT...
RESULTING IN A BROAD LOW AMPLITUDE FLOW ACRS SRN CANADA AND THE
NRN CONUS BY THE LATTER HALF OF NEXT WEEK.

THE PROXIMITY OF THE UPR RIDGE WL KEEP A WARM AND HUMID AIR MASS
ACRS THE AREA THROUGH EARLY NEXT WEEK. THAT WL RESULT IN ABV
NORMAL TEMPS FOR MUCH OF THE FCST PERIOD...BEFORE READINGS FALL
BACK CLOSER TO NORMAL DURING THE LATTER PART OF THE PERIOD.

AMPLE MOISTURE WL BE ACRS THE AREA TO FUEL PRECIPITATION. BUT
FORCING WL BE SPARSE EARLY AS THE UPR RIDGE DOMINATES. THEN WHEN
THE PRIMARY SHRTWV EJECTS FM THE WRN TROF...IT WL TRACK PRETTY
FAR W OF THE AREA. SO ESTIMATING PCPN IS A BIT TRICKY. IT STILL
LOOKS LIKE ENOUGH OPPORTUNITIES FOR PCPN TO GET AOA AMNTS AT MOST
LOCATIONS...THOUGH THAT DOESN/T SEEM LIKE AS MUCH OF LOCK AS IT
DID A COUPLE DAYS AGO.
&&

.SHORT TERM...TODAY...TONIGHT...AND SATURDAY
ISSUED AT 442 AM CDT FRI AUG 22 2014

LOTS OF FCST ISSUES TO SORT OUT THIS MORNING...THE FIRST OF WHICH
IS FOG. ENDED UP WITH KIND OF A WEIRD PATTERN TO THE DENSE FOG
ADVISORY...BUT...THAT/S WHERE THE DENSE FOG IS OCCURRING. CENTRAL
WI GOT THE MOST RAIN YDA...RESULTING IN DENSE FOG THERE. THE EAST
DID NOT GET NEARLY AS MUCH RAIN...AND LGT ELY FLOW WAS LIKELY
KEEPING THE ATM STIRRED UP ENOUGH TO GET FOR ST AND LESS FG.
WEBCAMS AND A CALL THE WINNEBAGO SHERIFF INDICATED THAT THE FOG
WAS NOT DENSE ENOUGH TO SIGNIFICANTLY IMPACT TRAVEL. THE EXCEPTION
WAS ALONG THE LAKESHORE...WHERE THAT ELY FLOW WAS BRINGING MOIST
AIR ACRS THE RELATIVELY COOL WATERS OF THE LAKE...THUS ENHANCING
FG PRODUCTION. THINK THIS PATTERN WL HOLD THROUGH THE MORNING
COMMUTE...BUT WL CONT TO MONITOR AND CAN ADJUST IF NEEDED.

SCT SHRA CONTD ACRS NRN WI. THEY DON/T LOOK LIKE MUCH ON RADAR...
BUT OB SITES BEING AFFECTED INDICATE BRIEF R+ AND UP TO 1/4 INCH
PCPN AMNTS. THOSE SHOULD GRADUALLY SHIFT E THIS MORNING.

CONFIDENCE IN THE PCPN FCST FOR THE REST OF THE SHORT-TERM IS
ABOUT AS LOW AS IT CAN GET. SOME OF THAT STEMS FM MISJUDGING THE
BEHAVIOR OF THE TSTM COMPLEX YDA MORNING...WHICH REALLY MESSED UP
THE PCPN FCST FOR YDA AFTN AND EVENING. BUT THERE ARE CONFLICTING
INDICATIONS FOR PCPN TDA/TNGT AS WELL. FAVORING NO PCPN...UPR
HEIGHTS WL BE RISING AS RIDGE BUILDS OVER THE AREA. FLOW WL ALSO
TREND MORE SHARPLY ANTICYCLONIC WITH TIME. BUT ON THE OTHER
HAND...PRETTY MUCH EVERY MODEL PRODUCED SCT PCPN ACRS THE AREA AT
SOME POINT TDA AND/OR TNGT. AND AT LOW-LEVELS...DIFFUSE SFC WV
ACRS MN WL BE SHIFTG SE INTO THE AREA THIS AFTN. THAT WL GENERATE
SOME LOW-LEVEL CONVERGENCE. IN ADDITION...UNLESS ST HOLDS ON ALL
DAY...WOULD EXPECT AT LEAST SOME SUN...GIVING THE ATM A CHC TO
DESTABLIZE. CONSIDERING THESE FACTORS...AND THAT SPC HAS A 5 PCT
CHC OF SVR ACRS THE AREA IN THE SWODY1...WAS JUST NOT COMFORTABLE
GOING TOTALLY DRY. WENT WITH PRETTY LOW POPS...BUT RAN WITH ISOLD
TSRA DURING THE AFTN AND EVENING. CERTAINLY COVERAGE WON/T BE
GREAT WITH MOST AREAS REMAINING DRY...BUT JUST COULD NOT COMMIT TO
TOTALLY DRY FCST.

SHRTWV EJECTING OUT OF THE WRN TROF WL BEGIN TO DRIVE DEEPENING
CYCLONE TOWARD THE NRN PLAINS SAT. THAT SHOULD LEAD TO
REORGANIZATION OF THE LOW-LEVEL FLOW...AND RESUMED ISENT LIFT IN
THE MAIN FRONTAL ZONE. SO CHC FOR TSRA WL SPREAD INTO THE SW PART
OF THE FCST AREA DURING THE DAY.

ADJUSTED TEMPS BASED ON BLEND OF THE LATEST GUIDANCE PRODUCTS...
THOUGH NORMALLY RELIABLE ECMWF/ECMWF-MOS PRODUCTS SEEMED A BIT TOO
COOL WITH MAXES TDA/SAT.

.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY
ISSUED AT 442 AM CDT FRI AUG 22 2014

THE HIGHLY AMPLIFIED FLOW CONSISTING OF AN UPR RDG FROM THE DEEP
SOUTH TO NEW ENGLAND AND AN UPR TROF OVER THE NW 1/4 OF THE CONUS
TO PERSIST INTO EARLY NEXT WEEK. PCPN CHCS THRU MON TO REVOLVE
AROUND THE MOVEMENT OF A WRMFNT/CDFNT COMBINATION WITH AT LEAST
CHC POPS NECESSARY. MDLS SEEM IN AGREEMENT IN MOVING THE UPR TROF
ACROSS SRN CANADA/NRN TIER OF STATES DURING THE MIDDLE OF NEXT
WEEK...THEREBY KEEPING THE WEATHER UNSETTLED OVER NE WI. TRYING TO
DETERMINE WHAT PERIOD(S) TO PLACE THE HIGHER POPS CONTS TO BE THE
HARDEST PART OF THE FCST. TEMPS TO BE ABOVE NORMAL THRU TUE BEFORE
DROPPING BACK TO AROUND NORMAL.

A BROAD S-SW FLOW TO BE OVER NE WI SAT NGT AS THE AREA TO RESIDE
BETWEEN THE UPR RDG JUST TO OUR EAST AND THE DEEP UPR TROF (NEARLY
CLOSED UPR LOW) SITUATED OVER W-CNTRL CANADA/NRN ROCKIES. AT THE
SFC...LOW PRES TO BE IN THE VICINITY OF ERN ND OR WRN MN WITH A
WRMFNT STRETCHED SEWD TOWARD SRN WI. PERSISTENT WAA TO COMBINE
WITH THE WRMFNT TO BRING AT LEAST CHC POPS TO THE ENTIRE FCST
AREA. PW VALUES REMAIN HIGH (1.5-2.0")...THUS ANY SHWR OR TSTM WL
HAVE THE ABILITY TO PRODUCE HEAVY RAINFALL.

THE WRMFNT IS PROGGED TO LIFT NORTH OF THE FCST AREA SUNDAY
MORNING...LEAVING A VERY WARM/HUMID/CAPPED ENVIRONMENT FOR SUNDAY
AFTERNOON. MAY LEAVE A SMALL POP IN THE NORTH IN CASE THE WRMFNT
SLOWS DOAN...BUT ANTICIPATE MOST OF THE DAY TO BE DRY. 8H TEMPS
RISE TO BETWEEN +20 AND +22C WHICH WOULD SEND MAX TEMPS TO AROUND
THE 90 DEG MARK ACROSS PARTS OF CNTRL WI. THESE TEMPS...WHEN
COMBINED WITH DEW POINTS IN THE UPR 60S TO LWR 70S...WOULD PRODUCE
HEAT INDICES IN THE MID TO UPR 90S. MAY NEED TO MENTION THIS
POSSIBILITY IN THE HWO.

AS THE UPR TROF LIFTS E-NE INTO THE VICINITY OF LAKE WINNIPEG
SUNDAY NGT...IT WL HELP SEND A CDFNT TOWARD THE WRN GREAT LAKES
DURING THE OVRNGT HOURS. THIS FNT DRIVING INTO A WARM/MOIST/UNSTABLE
AIR MASS SHOULD GENERATE SHWRS/TSTMS TOWARD NE WI AND HAVE PLACED
THE HIGHEST POPS OVER N-CNTRL WI...MAINLY AFTER MIDNGT. MDLS DIFFER
AS TO HOW FAST TO BRING THIS CDFNT THRU THE REST OF WI ON MON. THE
UPR RDG TO STILL RESIDE FROM THE DEEP SOUTH TOWARD NEW ENGLAND...
THUS PROVIDING A ROADBLOCK AND ONE WOULD FIGURE...A SLOWER FRONTAL
MOVEMENT. IT MAY TAKE MOST OF MON FOR THE FNT JUST TO CLEAR NE WI.
THEREFORE...HAVE KEPT A CHC OF SHWRS/TSTMS IN THE FCST FOR MON...
ALTHO N-CNTRL/CNTRL WI COULD SEE THE PCPN THREAT DIMINISH IN THE
AFTERNOON IF THE FNT CAN MOVE FAR ENUF. TEMPS SHOULD BE COOLER
WITH THICKER CLOUDS/PCPN AROUND...BUT STILL REMAIN QUITE MUGGY.

THIS CDFNT WL EVENTUALLY PULL UP STNRY MON NGT AS IT RUNS INTO THE
UPR RDG. EXACTLY WHERE THIS OCCURS WL DETERMINE THE EXTENT OF POPS
OVER THE REGION. THE FNT COULD STALL ANYWHERE FROM CNTRL WI TO NRN
IL...THUS MAKING THE FCST FOR MON NGT INTO TUE QUITE CHALLENGING.
HAVE SETTLED WITH THE FNT STALLING OVER SRN WI...CLOSEST TO THE
ECMWF SOLUTION...THEREFORE A SLIGHTLY HIGHER CHC POP FOR CNTRL/
E-CNTRL WI. FOR TUE...THE MAIN UPR TROF TO BE MOVING INTO THE NRN/
CNTRL PLAINS WHICH MAY HELP TO LIFT THE STALLED BOUNDARY A BIT
FARTHER NORTH. THIS WOULD CONT THE THREAT OF ADDITIONAL SHWRS/
TSTMS ACROSS NE WI.

THE UPR TROF IS FCST TO SWEEP EAST AND REACH THE GREAT LAKES ON
WED. A CDFNT WL PRECEDE THE UPR TROF INTO WI TUE NGT AND SET OFF
THE NEXT ROUND OF SHWRS AND TSTMS ACROSS THE FCST AREA. ONCE
AGAIN...ENUF MOISTURE TO BE PRESENT FOR LOCALLY HEAVY RAINFALL TO
OCCUR. PCPN CHCS WOULD CARRY OVER INTO WED AND THEN GRADUALLY
DIMINISH FROM WEST TO EAST AS WEAK HI PRES MOVES INTO THE UPR MS
VALLEY. THIS AREA OF HI PRES IS EXPECTED TO PUSH INTO THE GREAT
LAKES FOR NEXT THU AND BRING SUNSHINE BACK TO THE REGION. A COOLER/
LESS HUMID AIR MASS TO ARRIVE BY THIS TIME WITH MAX TEMPS AT OR
EVEN SLIGHTLY BELOW NORMAL.
&&

.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 442 AM CDT FRI AUG 22 2014

POOR FLIGHT CONDITIONS WL LINGER THROUGH AT LEAST MID-MORNING AS
WIDESPREAD FG/ST CONT ACRS THE AREA. CONDITIONS SHOULD IMPROVE
DURING THE DAY...BUT WL LIKELY DETERIORATE QUICKLY AGAIN TNGT.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR WIZ018-030-
035-036-040-045-050.
&&

$$

SYNOPSIS.......SKOWRONSKI
SHORT TERM.....SKOWRONSKI
LONG TERM......KALLAS
AVIATION.......SKOWRONSKI





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