WTNT43 KNHC 041437
TCDAT3
 
TROPICAL STORM MICHAEL DISCUSSION NUMBER   4
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 AM AST TUE SEP 04 2012
 
 
THE CLOUD PATTERN HAS BECOME A LITTLE BETTER ORGANIZED WITH AN AREA
OF CONCENTRATED DEEP ORGANIZED CONVECTION NEAR THE CENTER. THE
UPPER-LEVEL OUTFLOW...HOWEVER...EXISTS ONLY ON THE EASTERN
SEMICIRCLE AT THIS TIME. SATELLITE INTENSITY ESTIMATES FROM TAFB...
SAB AND CIMSS ARE 2.5 ON THE DVORAK SCALE...SUGGESTING AN INITIAL
INTENSITY OF 35 KNOTS.  THE DEPRESSION IS NOW TROPICAL STORM
MICHAEL...THE 13TH NAMED STORM OF THE 2012 SEASON. ONLY 2005 AND
2011 HAD THE 13TH NAMED STORM FORM EARLIER THAN 4 SEPTEMBER.
 
MICHAEL IS A VERY SMALL TROPICAL CYCLONE AND IT IS EMBEDDED WITHIN
AN ENVIRONMENT NOT TOO CONDUCIVE FOR SIGNIFICANT INTENSIFICATION.
IN FACT...ONLY A SMALL INCREASE IN THE SHEAR COULD LEAD TO
WEAKENING. IF MICHAEL SURVIVES A COUPLE OF DAYS...THERE IS AN
OPPORTUNITY FOR SLIGHT STRENGTHENING AS AN UPPER-LOW FORMS SOUTH OF
THE CYCLONE RESULTING IN A LESS HOSTILE UPPER-LEVEL ENVIRONMENT.
THE NHC FORECAST CALLS FOR NOT MUCH CHANGE IN INTENSITY AND ALLOWS
SLIGHT INTENSIFICATION BY THE LATTER PART OF THE FORECAST...BUT NOT
AS HIGH AS INDICATED BY THE STATISTICAL INTENSITY MODELS.
 
MICHAEL IS MOVING TOWARD THE NORTH-NORTHWEST OR 340 DEGREES AT 4
KNOTS...EMBEDDED WITHIN LIGHT SOUTHERLY STEERING CURRENTS WEST OF
THE SUBTROPICAL RIDGE.  GLOBAL MODELS ARE FORECASTING A SHORT WAVE
TROUGH TO BYPASS MICHAEL...LEAVING THE STORM WITHIN A WEAK STEERING
FLOW. THIS PATTERN SHOULD KEEP MICHAEL MEANDERING BETWEEN THE
NORTH-NORTHWEST AND NORTHWARD THROUGH FIVE DAYS. ALTHOUGH THE
GUIDANCE IS NOT IN GOOD AGREEMENT...PRIMARILY IN SPEED...MOST OF
THE MODELS MOVE MICHAEL ON A GENERAL NORTHWARD TREND. THE NHC
FORECAST IS IN BETWEEN THE GFS AND THE ECMWF.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  04/1500Z 27.0N  43.5W   35 KT  40 MPH
 12H  05/0000Z 27.7N  44.0W   35 KT  40 MPH
 24H  05/1200Z 28.5N  44.2W   35 KT  40 MPH
 36H  06/0000Z 29.0N  44.0W   35 KT  40 MPH
 48H  06/1200Z 29.5N  43.5W   35 KT  40 MPH
 72H  07/1200Z 30.5N  43.4W   40 KT  45 MPH
 96H  08/1200Z 31.5N  43.5W   40 KT  45 MPH
120H  09/1200Z 33.0N  44.5W   35 KT  40 MPH
 
$$
FORECASTER AVILA
 

WTNT43 KNHC 042052
TCDAT3
 
TROPICAL STORM MICHAEL DISCUSSION NUMBER   5
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 PM AST TUE SEP 04 2012
 
MICHAEL HAS BECOME BETTER ORGANIZED DURING THE DAY.  ALTHOUGH
GEOSTATIONARY SATELLITE IMAGES INDICATE SOME WARMING OF THE CLOUD
TOPS DURING THE PAST HOUR OR SO...RECENT MICROWAVE DATA INDICATE
THAT A CURVED BAND NOW WRAPS ABOUT THREE-QUARTERS OF THE WAY AROUND
THE CENTER.  THE INITIAL WIND SPEED IS SET AT 45 KT...BASED ON
DVORAK CLASSIFICATIONS FROM BOTH TAFB AND SAB AND DATA FROM AN
EARLIER PARTIAL ASCAT PASS THAT SHOWED A COUPLE OF 35 TO 40 KT WIND
VECTORS JUST NORTHWEST OF THE CENTER.  ONLY SLIGHT ADDITIONAL
STRENGTHENING IS FORECAST IN THE SHORT TERM AS WESTERLY SHEAR IS
EXPECTED TO INCREASE OVER THE SMALL CYCLONE DURING THE NEXT DAY OR
TWO.  AFTER THAT TIME...HOWEVER...AN UPPER-LEVEL LOW IS EXPECTED TO
CUT OFF TO THE SOUTHWEST OF MICHAEL.  AS THAT OCCURS...A NARROW
RIDGE IS EXPECTED TO BUILD OVER THE CYCLONE...RESULTING IN A
REDUCTION OF VERTICAL SHEAR.  THE OFFICIAL INTENSITY FORECAST IS
INCREASED FROM THE PREVIOUS ADVISORY AND LIES FAIRLY CLOSE TO...BUT
A LITTLE LOWER THAN...THE SHIPS AND LGEM GUIDANCE.

MICHAEL IS MOVING SLOWLY NORTH-NORTHWESTWARD...BUT IS EXPECTED TO
TURN TOWARD THE NORTHEAST IN A DAY OR SO AS A MID-LATITUDE TROUGH
MOVES EASTWARD ACROSS THE CENTRAL ATLANTIC.  AFTER THIS TOUGH
BYPASSES MICHAEL...A RIDGE IS FORECAST TO BUILD OVER THE CENTRAL
ATLANTIC TO THE NORTH OF THE CYCLONE.  AS THE RIDGE SLIDES
EASTWARD IN A FEW DAYS...IT SHOULD CAUSE MICHAEL TO TURN
NORTHWESTWARD.  THE TRACK GUIDANCE IS IN GENERAL AGREEMENT ON 
THIS SCENARIO AND THE OFFICIAL FORECAST LIES BETWEEN THE MODEL
CONSENSUS AND THE PREVIOUS NHC TRACK.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  04/2100Z 27.5N  43.7W   45 KT  50 MPH
 12H  05/0600Z 28.1N  43.9W   50 KT  60 MPH
 24H  05/1800Z 28.8N  43.8W   50 KT  60 MPH
 36H  06/0600Z 29.4N  43.3W   50 KT  60 MPH
 48H  06/1800Z 29.9N  42.9W   50 KT  60 MPH
 72H  07/1800Z 30.9N  43.2W   55 KT  65 MPH
 96H  08/1800Z 32.0N  44.0W   60 KT  70 MPH
120H  09/1800Z 33.5N  46.0W   60 KT  70 MPH
 
$$
FORECASTER BROWN
 

WTNT43 KNHC 050238
TCDAT3
 
TROPICAL STORM MICHAEL DISCUSSION NUMBER   6
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 PM AST TUE SEP 04 2012
 
THE SATELLITE PRESENTATION OF THE STORM HAS NOT CHANGED MUCH SINCE
THE PREVIOUS ADVISORY...EXCEPT FOR A SLIGHT INCREASE IN CENTRAL
CONVECTION.  DVORAK SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB
REMAIN AT 45 KT...SO THE CURRENT INTENSITY IS HELD AT THAT VALUE. 
WESTERLY SHEAR OVER MICHAEL IS PREDICTED TO STAY MODERATE TO STRONG
FOR THE NEXT DAY OR SO...WHICH SHOULD PREVENT SIGNIFICANT
STRENGTHENING IN THE SHORT TERM.  LATER IN THE FORECAST
PERIOD...THE GLOBAL MODELS SHOW AN UPPER-LEVEL LOW CUTTING OFF AND
MOVING TO THE SOUTHWEST OF THE TROPICAL CYCLONE.  THIS COULD RESULT
IN DECREASING SHEAR AND AN ENVIRONMENT MORE CONDUCIVE FOR
STRENGTHENING.  THE OFFICIAL WIND SPEED FORECAST IS CLOSE TO THE
LATEST LGEM GUIDANCE AND THE INTENSITY MODEL CONSENSUS.
 
MICHAEL IS NEAR A COL REGION BETWEEN TWO ANTICYCLONES IN THE
MID-LEVEL FLOW... AND HAS MOVED VERY LITTLE SINCE THE LAST
ADVISORY.  THE STORM SHOULD BEGIN TO MOVE SLOWLY NORTHWARD TO
NORTHEASTWARD DURING THE NEXT COUPLE OF DAYS DUE TO A SHORTWAVE
TROUGH TO THE NORTH.  THIS TROUGH IS FORECAST TO MOVE OUT OF THE
AREA IN 48-72 HOURS...HOWEVER...WITH AN ANTICYCLONE DEVELOPING TO
THE NORTHWEST OF MICHAEL THERAFTER.  THESE CHANGES IN THE STEERING
CURRENTS SHOULD CAUSE THE TROPICAL CYCLONE TO TURN TOWARD THE LEFT
LATER IN THE FORECAST PERIOD...AND MICHAEL IS EXPECTED TO
EVENTUALLY MOVE AROUND THE EASTWARD-MOVING ANTICYCLONE.  THE
OFFICIAL TRACK FORECAST IS FAIRLY SIMILAR TO THE PREVIOUS ONE AND
LIES BETWEEN THE ECMWF AND THE GFS SOLUTIONS.
 
DATA FROM A RECENT ASCAT OVERPASS CONFIRM THAT MICHAEL IS A VERY
SMALL TROPICAL STORM. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  05/0300Z 27.4N  43.7W   45 KT  50 MPH
 12H  05/1200Z 28.1N  43.9W   50 KT  60 MPH
 24H  06/0000Z 28.9N  43.5W   50 KT  60 MPH
 36H  06/1200Z 29.6N  42.8W   50 KT  60 MPH
 48H  07/0000Z 30.0N  42.5W   55 KT  65 MPH
 72H  08/0000Z 31.2N  43.0W   60 KT  70 MPH
 96H  09/0000Z 32.0N  44.0W   65 KT  75 MPH
120H  10/0000Z 33.0N  45.5W   65 KT  75 MPH
 
$$
FORECASTER PASCH
 

WTNT43 KNHC 050840
TCDAT3
 
TROPICAL STORM MICHAEL DISCUSSION NUMBER   7
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 AM AST WED SEP 05 2012
 
DEEP CONVECTION CONTINUES TO PULSATE NEAR AND EAST OF THE ESTIMATED
CENTER LOCATION...HOWEVER THE CONVECTIVE CANOPY IS SOMEWHAT
ELONGATED TOWARD THE NORTHEAST. THE INITIAL INTENSITY REMAINS 45 KT
IN AGREEMENT WITH THE LATEST SATELLITE ESTIMATES FROM TAFB AND SAB.
UW-CIMSS AND THE SHIPS MODEL INDICATE THAT WEST-NORTHWESTERLY SHEAR
OF ABOUT 20 KT IS AFFECTING THE CYCLONE...AND THIS SHEAR IS EXPECTED
TO CONTINUE FOR THE NEXT DAY OR SO. DURING THAT TIME...ONLY SLIGHT
STRENGTHENING IS SHOWN BY MOST OF THE INTENSITY GUIDANCE...AND THIS
TREND IS REFLECTED IN THE NHC FORECAST. THE SHEAR SHOULD BEGIN TO
DECREASE BY 48 HOURS...AND THE ENVIRONMENT APPEARS FAVORABLE FOR
SOME INTENSIFICATION BY THAT TIME. THE NEW NHC INTENSITY FORECAST
IS CLOSE TO THE IVCN INTENSITY CONSENSUS THROUGH THE PERIOD.

THE INITIAL MOTION ESTIMATE IS 360/04...AS MICHAEL APPEARS TO BE
RESPONDING TO A SHORTWAVE TROUGH PASSING TO THE NORTH. ONCE THE
TROUGH MOVES BY IN ABOUT 48 HOURS...THE GLOBAL MODELS SHOW A RIDGE
BUILDING TO THE NORTHWEST AND THEN TO THE NORTH OF THE TROPICAL
CYCLONE...WHICH SHOULD RESULT IN A SLOW NORTHWESTWARD MOTION AT
DAYS 3 THROUGH 5. THE NEW NHC TRACK IS ALONG BUT A LITTLE FASTER
THAN THE PREVIOUS FORECAST THROUGH 72 HOURS. AFTER THAT TIME THE
NHC FORECAST HAS BEEN SHIFTED A LITTLE TO THE RIGHT AND LIES
BETWEEN THE ECMWF AND GFS MODELS.

FORECAST POSITIONS AND MAX WINDS
 
INIT  05/0900Z 28.1N  43.9W   45 KT  50 MPH
 12H  05/1800Z 28.6N  43.7W   45 KT  50 MPH
 24H  06/0600Z 29.4N  43.1W   50 KT  60 MPH
 36H  06/1800Z 30.0N  42.6W   50 KT  60 MPH
 48H  07/0600Z 30.7N  42.8W   55 KT  65 MPH
 72H  08/0600Z 31.8N  43.7W   65 KT  75 MPH
 96H  09/0600Z 33.0N  45.0W   70 KT  80 MPH
120H  10/0600Z 34.0N  46.0W   65 KT  75 MPH
 
$$
FORECASTER BRENNAN
 

WTNT43 KNHC 062031
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  15
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 PM AST THU SEP 06 2012
 
RECENT MICROWAVE AND ENHANCED BD-CURVE INFRARED IMAGERY INDICATE
SOME WEAKENING OF THE INNER CORE...PARTICULARLY IN THE SOUTHWEST
QUADRANT.  CONSEQUENTLY...THE FINAL SUBJECTIVE DVORAK INTENSITY
ESTIMATES FROM BOTH AGENCIES HAVE DECREASED TO 77 KT.
HOWEVER...THE INITIAL INTENSITY HAS BEEN LOWERED JUST A BIT TO 95
KT IN CONSIDERATION OF THE 105 KT UW-CIMSS ADT ESTIMATE.  GRADUAL
WEAKENING THROUGH THE ENTIRE PERIOD IS REFLECTED IN THE OFFICIAL
INTENSITY FORECAST...PRIMARILY DUE TO EITHER A MID- TO UPPER-LEVEL
MID-LATITUDE TROUGH APPROACHING FROM THE NORTHWEST...OR THE LARGE
OUTFLOW ASSOCIATED WITH HURRICANE LESLIE.  THE NHC INTENSITY
FORECAST CALLS FOR GRADUAL WEAKENING THROUGH 5 DAYS AND IS A
COMPROMISE BETWEEN THE IVCN CONSENSUS AND THE FLORIDA STATE
UNIVERSITY SUPERENSEMBLE.
 
THE INITIAL MOTION ESTIMATE IS 020/6...WITH A TURN TO THE NORTH AND
THE NORTH-NORTHWEST OCCURRING DURING THE NEXT 24 HOURS.  THE GLOBAL
AND HURRICANE MODELS HAVE BECOME MUCH MORE ALIGNED WITH A SIMILAR
NORTH-NORTHWESTWARD TO NORTHWESTWARD MOTION...ALBEIT WITH
SIGNIFICANT FORWARD SPEED DIFFERENCES BEYOND 48 HOURS.  THE
GUIDANCE NOW APPEARS TO BE RESPONDING MORE TO A STEERING
ENVIRONMENT PRODUCED BY A SIGNIFICANT BREAK IN THE SUBTROPICAL
RIDGE NEAR 45W AND THE AZORES HIGH ANCHORED TO THE EAST.  THE GFS
AND THE GFDL MODELS ARE QUITE A BIT FASTER BEYOND DAY 4 WHILE THE
REMAINING AVAILABLE GUIDANCE AGREE MORE ON A SLOWER 5-7 KT FORWARD
MOTION.  THE NHC FORECAST IS VERY CLOSE TO THE PAST 6 HOUR TRACK
FORECAST...BUT A LITTLE FASTER AT DAY 5 IN ORDER TO HEDGE CLOSER TO
THE TVCA CONSENSUS WHICH INCORPORATES THE FASTER GFDL AND GFS.
 
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  06/2100Z 30.6N  41.0W   95 KT 110 MPH
 12H  07/0600Z 31.1N  41.0W   90 KT 105 MPH
 24H  07/1800Z 31.7N  41.5W   85 KT 100 MPH
 36H  08/0600Z 32.2N  42.1W   80 KT  90 MPH
 48H  08/1800Z 32.8N  42.6W   80 KT  90 MPH
 72H  09/1800Z 34.0N  43.5W   75 KT  85 MPH
 96H  10/1800Z 36.2N  45.3W   70 KT  80 MPH
120H  11/1800Z 40.0N  46.5W   60 KT  70 MPH
 
$$
FORECASTER ROBERTS
 

WTNT43 KNHC 070233
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  16
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 PM AST THU SEP 06 2012
 
THE CONVECTIVE COLD TOPS HAVE BECOME A LITTLE LESS SYMMETRIC AROUND
THE EYE DURING THE PAST FEW HOURS...AND RECENT MICROWAVE DATA
INDICATE THAT MICHAEL POSSESSES A THIN BUT CLOSED EYEWALL.  DVORAK
CURRENT INTENSITY ESTIMATES ARE NOW 90 KT FROM TAFB AND 77 KT FROM
SAB...AND THE LATEST UW-CIMSS ADT ESTIMATE IS T4.9/5.2.  THE
INTENSITY IS LOWERED A BIT TO 90 KT BASED ON A BLEND OF THESE DATA.

MICHAEL HAS FOUND ITSELF STUCK BETWEEN TWO MID-/UPPER-LEVEL LOWS...
EACH ROUGHLY EQUIDISTANT TO THE NORTHEAST AND SOUTHWEST OF THE
HURRICANE.  THE COMPETING FLOWS AROUND THE LOWS HAVE CAUSED MICHAEL
TO SLOW DOWN...AND THE INITIAL MOTION IS ESTIMATED TO BE 025/4 KT. 
THE STEERING CURRENTS OVER THE CENTRAL ATLANTIC ARE EXPECTED TO
REMAIN WEAK...AND MICHAEL IS FORECAST TO CREEP NORTHWARD TO
NORTHWESTWARD DURING THE NEXT 3 TO 4 DAYS.  THE GLOBAL MODELS THEN
AGREE THAT THE CYCLONE WILL ACCELERATE NORTHWARD BY DAY 5 AHEAD OF
AN APPROACHING MID-LATITUDE TROUGH...AND WITHIN THE SOUTHERLY FLOW
AHEAD OF HURRICANE LESLIE.  THE UPDATED TRACK FORECAST IS VERY
SIMILAR TO THE 21Z FORECAST DURING THE FIRST 72 HOURS...AND IS THEN
A LITTLE TO THE WEST AND FASTER BY DAY 5 TO BE CLOSER TO THE MODEL
CONSENSUS TVCA.

ACCORDING TO THE SHIPS DIAGNOSTICS...MICHAEL SHOULD BE IN A
RELATIVELY SHEAR-FREE ENVIRONMENT FOR THE NEXT 72 HOURS. 
HOWEVER...THE UPPER-LEVEL PATTERN OVER THE CENTRAL ATLANTIC IS
COMPLEX...AND IT IS POSSIBLE THAT THE OUTFLOW FROM LESLIE COULD
AFFECT MICHAEL SOONER THAN SHOWN BY THE SHIPS GUIDANCE.  THE NHC
INTENSITY FORECAST CONTINUES TO SHOW ONLY GRADUAL WEAKENING DURING
THE NEXT 4 DAYS...WHICH IS SUPPORTED BY MOST OF THE GUIDANCE. 
FASTER WEAKENING IS EXPECTED BY DAY 5 ONCE THE DEEP-LAYER SHEAR
BECOMES DECIDEDLY STRONGER...AND MICHAEL COULD BE CLOSE TO BEING
EXTRATROPICAL BY THAT TIME AS WELL.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/0300Z 30.8N  40.8W   90 KT 105 MPH
 12H  07/1200Z 31.2N  40.9W   85 KT 100 MPH
 24H  08/0000Z 31.7N  41.5W   80 KT  90 MPH
 36H  08/1200Z 32.3N  42.0W   80 KT  90 MPH
 48H  09/0000Z 33.0N  42.5W   75 KT  85 MPH
 72H  10/0000Z 34.5N  44.0W   70 KT  80 MPH
 96H  11/0000Z 36.5N  46.0W   65 KT  75 MPH
120H  12/0000Z 43.0N  47.0W   50 KT  60 MPH
 
$$
FORECASTER BERG
 

WTNT43 KNHC 070836
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  17
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 AM AST FRI SEP 07 2012
 
THE WEAKENING TREND OF MICHAEL APPEARS TO HAVE STOPPED FOR NOW.
INFRARED SATELLITE IMAGES INDICATE THAT CLOUD TOPS HAVE COOLED
AROUND THE EYE...AND THE OVERALL CLOUD PATTERN IS A LITTLE MORE
SYMMETRIC THAN IT WAS 6 HOURS AGO. IN ADDITION...A RECENT AMSU
MICROWAVE IMAGE SHOWS THAT THE EYEWALL IS A LITTLE WIDER THAN IT
WAS LAST NIGHT. AN AVERAGE OF THE LATEST SATELLITE INTENSITY
ESTIMATES FROM TAFB...SAB...AND UW-CIMSS SUPPORTS MAINTAINING THE
INITIAL WIND SPEED AT 90 KT...BUT MICHAEL COULD BE A LITTLE
STRONGER.
 
MICHAEL IS MOVING SLOWLY NORTHWARD AT ABOUT 3 KT. THE STEERING FLOW
IS QUITE WEAK AT THE MOMENT WITH A TROUGH PASSING TO THE NORTH OF
MICHAEL AND A PAIR OF CUT OFF LOWS LOCATED TO THE SOUTHWEST AND
SOUTHEAST OF THE HURRICANE. A SLOW NORTHWESTWARD MOTION IS FORECAST
FOR THE NEXT 2 TO 3 DAYS AS THE SYSTEM REMAINS IN WEAK STEERING
CURRENTS. AFTER THAT...THE COMBINED INFLUENCES OF A STRENGTHENING
RIDGE TO THE NORTH AND EAST OF MICHAEL AND A TROUGH OVER THE
WESTERN ATLANTIC SHOULD CAUSE THE CYCLONE TO ACCELERATE TO THE
NORTH-NORTHWEST OR NORTH. THE OFFICIAL TRACK FORECAST IS A LITTLE
TO THE LEFT OF THE PREVIOUS ONE AND FAIRLY CLOSE TO THE CONSENSUS
AIDS...TVCA AND TV15.
 
THE INTENSITY GUIDANCE IS IN FAIR AGREEMENT IN SHOWING LITTLE CHANGE
IN STRENGTH OR SLIGHT WEAKENING OVER THE NEXT COUPLE OF DAYS AS
MICHAEL MOVES OVER 27 TO 28C WATERS AND REMAINS IN GENERALLY LOW
WIND SHEAR CONDITIONS. AFTER 48 HOURS...THE WATER TEMPERATURES
BENEATH THE CYCLONE LOWER AND THE SHEAR SHOULD INCREASE...IN PART
DUE TO THE OUTFLOW OF HURRICANE LESLIE. THE OFFICIAL FORECAST IS
NUDGED UPWARD FOR THE NEXT DAY DUE TO THE RECENT IMPROVEMENT IN THE
ORGANIZATION OF MICHAEL...BUT IS OTHERWISE UNCHANGED FROM THE
PREVIOUS ONE. THIS FORECAST IS CLOSE TO THE INTENSITY MODEL
CONSENSUS AND THE LGEM GUIDANCE. SOME OF THE MODELS SUGGEST THAT
MICHAEL COULD BE A POST-TROPICAL CYCLONE BY DAY 5.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/0900Z 31.0N  40.8W   90 KT 105 MPH
 12H  07/1800Z 31.4N  41.1W   90 KT 105 MPH
 24H  08/0600Z 31.8N  41.6W   85 KT 100 MPH
 36H  08/1800Z 32.4N  42.2W   80 KT  90 MPH
 48H  09/0600Z 33.0N  42.8W   75 KT  85 MPH
 72H  10/0600Z 34.3N  44.5W   70 KT  80 MPH
 96H  11/0600Z 38.0N  46.5W   60 KT  70 MPH
120H  12/0600Z 45.5N  47.0W   50 KT  60 MPH
 
$$
FORECASTER CANGIALOSI
 

WTNT43 KNHC 071451
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  18
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 AM AST FRI SEP 07 2012

THERE HAVE ONLY BEEN SMALL CHANGES WITH MICHAEL DURING THE LAST
SEVERAL HOURS.  SATELLITE IMAGES INDICATE THAT WHILE THE EYE HAS
BECOME SOMEWHAT OBSCURED WITH CIRRUS CLOUDS...THE EYEWALL
CONVECTION HAS GOTTEN A LITTLE DEEPER.  INTENSITY ESTIMATES RANGE
BETWEEN 90-100 KT...AND THE INITIAL WIND SPEED IS CONSERVATIVELY
KEPT AT 90 KT.  MODEL GUIDANCE IS CONSISTENTLY SHOWING MICHAEL
SLOWLY WEAKENING OVER THE NEXT FEW DAYS DUE TO LIGHT OR MODERATE
WESTERLY SHEAR AND GRADUALLY COOLING SSTS.  THE NEW NHC FORECAST IS
THE SAME AS THE PREVIOUS PREDICTION WHICH IS A BIT LOWER THAN THE
INTENSITY CONSENSUS.  A COMBINATION OF COLD WATERS AND STRONG SHEAR
SHOULD CAUSE THE SYSTEM TO BECOME POST-TROPICAL IN ABOUT 5 DAYS.  
 
THE HURRICANE HAS TURNED TOWARD THE NORTHWEST AT ABOUT 3 KT.  THIS
GENERAL TRACK AND SPEED IS EXPECTED FOR THE NEXT COUPLE OF DAYS
WHILE WEAK RIDGING PERSISTS OVER THE CENTRAL ATLANTIC.  THE RIDGE
SHOULD REBUILD TO THE EAST OF MICHAEL IN A FEW DAYS...CAUSING THE
CYCLONE TO TURN NORTHWARD.  MODEL GUIDANCE IS NOT IN GOOD AGREEMENT
AT LONG RANGE...PARTIALLY DUE TO A POSSIBLE INTERACTION OF MICHAEL
WITH LESLIE AS THE NEXT MID-LATITUDE TROUGH MOVES THROUGH THE
CANADIAN MARITIMES.  FOR NOW...THE NEW FORECAST WILL ASSUME THE
CYCLONE WILL STAY MOSTLY SEPARATE FROM LESLIE AND ENDS UP ONLY A
LITTLE FASTER THAN THE PREVIOUS ONE.  IF THE LATEST GFS MODEL IS
CORRECT...THIS TRACK FORECAST IS TOO SLOW AND NORTHWARD ADJUSTMENTS
WOULD HAVE TO BE MADE LATER TODAY.  
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/1500Z 31.2N  41.1W   90 KT 105 MPH
 12H  08/0000Z 31.5N  41.4W   90 KT 105 MPH
 24H  08/1200Z 32.0N  41.9W   85 KT 100 MPH
 36H  09/0000Z 32.7N  42.4W   80 KT  90 MPH
 48H  09/1200Z 33.3N  43.0W   75 KT  85 MPH
 72H  10/1200Z 34.7N  44.8W   70 KT  80 MPH
 96H  11/1200Z 39.5N  47.0W   60 KT  70 MPH
120H  12/1200Z 48.5N  46.0W   50 KT  60 MPH...POST-TROPICAL
 
$$
FORECASTER BLAKE
 

WTNT43 KNHC 072030
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  19
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 PM AST FRI SEP 07 2012
 
THE SATELLITE APPEARANCE OF MICHAEL HAS BEEN FLUCTUATING OVER THE
PAST SEVERAL HOURS...WITH PERHAPS THE OVERALL SYSTEM LOOKING A BIT
LESS ORGANIZED THAN SIX HOURS AGO.  ALTHOUGH THE RECENT T-NUMBERS
HAVE DECREASED...CURRENT INTENSITY ESTIMATES RANGE BETWEEN 90-102
KT...SO THE INITIAL WIND SPEED IS KEPT AT 90 KT.  THE STATISTICAL
AND DYNAMICAL MODELS ARE STILL SHOWING MICHAEL SLOWLY WEAKENING
OVER THE NEXT FEW DAYS...WITH THE NEGATIVE PRIMARY FACTORS BEING
SOME WESTERLY SHEAR AND COOLING WATERS.  THE LATEST NHC FORECAST IS
BASICALLY AN UPDATE OF THE PREVIOUS ONE...AND REMAINS ON THE LOW
SIDE OF THE INTENSITY CONSENSUS. 
 
MICHAEL CONTINUES TO MOVE TOWARD THE NORTHWEST AT ABOUT 3 KT.
MOST OF THE MODELS SUGGEST THIS GENERAL TRACK IS PROBABLE FOR THE
NEXT FEW DAYS...THOUGH THERE IS SOME HINT IN THE GUIDANCE THAT THE
HURRICANE COULD MOVE BRIEFLY TO THE WEST-NORTHWEST AS A SHORTWAVE
RIDGE BUILDS.  THE TRACK FORECAST HAS BEEN SHIFTED A BIT TO THE
WEST IN THE 48-96 HR TIME RANGE TO COME CLOSER TO THE TVCA
CONSENSUS.  THERE IS A LITTLE BETTER AGREEMENT ON THE LONG-TERM
FORECAST...WITH MORE OF THE RELIABLE GLOBAL MODELS KEEPING ENOUGH
SEPARATION FROM LESLIE SO THAT MICHAEL CURVES TO THE NORTH AND
NORTHEAST OUT TO SEA.  THIS SOLUTION IS FAVORED BY THE LATEST GFS
AND ECMWF RUNS...AND THE NEW NHC FORECAST IS ADJUSTED NORTHEASTWARD
TOWARD THOSE SOLUTIONS.  
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/2100Z 31.4N  41.3W   90 KT 105 MPH
 12H  08/0600Z 31.8N  41.8W   85 KT 100 MPH
 24H  08/1800Z 32.3N  42.2W   80 KT  90 MPH
 36H  09/0600Z 33.1N  42.6W   80 KT  90 MPH
 48H  09/1800Z 33.6N  43.1W   75 KT  85 MPH
 72H  10/1800Z 35.4N  45.4W   70 KT  80 MPH
 96H  11/1800Z 42.0N  47.5W   60 KT  70 MPH
120H  12/1800Z 52.5N  43.5W   50 KT  60 MPH...POST-TROPICAL
 
$$
FORECASTER BLAKE
 

WTNT43 KNHC 080244
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  20
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 PM AST FRI SEP 07 2012
 
THE CLOUD PATTERN OF MICHAEL IN INFRARED IMAGERY HAS CONTINUED TO
DEGRADE DURING THE PAST FEW HOURS...AND RECENT MICROWAVE DATA
INDICATE THAT THE RING OF DEEP CONVECTION AROUND THE CENTER IS OPEN
ON THE WEST SIDE.  THE LATEST SUBJECTIVE DVORAK NUMBERS ARE T4.0/5.0
FROM BOTH TAFB AND SAB AND HAVE FALLEN TO T4.4/4.8 FROM THE
UW-CIMSS ADT.  THE INTENSITY IS THEREFORE LOWERED TO 85 KT.
 
MICHAEL APPEARS TO HAVE BEEN SQUEEZED A BIT FROM THE NORTHWEST AND
SOUTHEAST BY THE SURROUNDING UPPER-LEVEL FLOW...WHICH COULD BE
CONTRIBUTING TO THE SLIGHT WEAKENING.  HOWEVER...THE DEEP-LAYER
SHEAR IS EXPECTED TO BE LIGHT FOR THE NEXT 36 HOURS...AND MICHAEL
IS NOT FORECAST TO CHANGE MUCH IN INTENSITY DURING THAT TIME.  THE
OUTFLOW FROM LESLIE SHOULD PRODUCE STRONG NORTHERLY SHEAR ON THE
ORDER OF 30-40 KT NEAR THE CYCLONE IN ABOUT 3 DAYS...AND MICHAEL IS
EXPECTED TO SUFFER MARKEDLY GIVEN ITS SMALL SIZE.  THE GLOBAL
MODELS THEN SHOW MICHAEL RUNNING INTO A WARM FRONT BY DAY 4...WHILE
OVER SEA SURFACE TEMPERATURES LESS THAN 20 DEGREES CELSIUS...SO THE
CYCLONE IS FORECAST TO BE POST-TROPICAL AT 96 HOURS AND ABSORBED BY
THE FRONT AT 120 HOURS.
 
THE INITIAL MOTION ESTIMATE IS 310/4 KT.  MICHAEL WILL CONTINUE TO
MOVE SLOWLY NORTHWESTWARD DURING THE NEXT 48-72 HOURS WHILE BEING
TRAPPED BETWEEN A RIDGE TO ITS EAST AND A DEVELOPING RIDGE TO ITS
NORTH.  AFTER 72 HOURS...THE CYCLONE WILL BECOME EMBEDDED IN THE
SOUTHERLY FLOW TO THE EAST OF LESLIE...AND IT IS FORECAST TO
ACCELERATE NORTHWARD UNTIL IT BECOMES ABSORBED WITHIN THE FRONTAL
ZONE.  THE TRACK MODELS ARE IN GENERALLY CLOSE PROXIMITY TO EACH
OTHER DURING THE FORECAST PERIOD...AND THE ONLY REAL UPDATE NEEDED
TO THE FORECAST WAS A SLIGHT SOUTHWESTWARD SHIFT OF THE 72-HOUR
POINT.

FORECAST POSITIONS AND MAX WINDS
 
INIT  08/0300Z 31.8N  41.8W   85 KT 100 MPH
 12H  08/1200Z 32.2N  42.1W   80 KT  90 MPH
 24H  09/0000Z 32.9N  42.5W   80 KT  90 MPH
 36H  09/1200Z 33.5N  43.0W   80 KT  90 MPH
 48H  10/0000Z 33.9N  43.8W   75 KT  85 MPH
 72H  11/0000Z 36.0N  46.5W   60 KT  70 MPH
 96H  12/0000Z 44.0N  47.0W   55 KT  65 MPH...POST-TROPICAL
120H  13/0000Z...ABSORBED BY A FRONT
 
$$
FORECASTER BERG
 

WTNT43 KNHC 080832
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  21
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 AM AST SAT SEP 08 2012
 
MICHAEL APPEARS TO BE MAINTAINING ITS STRENGTH. A RAGGED EYE HAS
BEEN OCCASIONALLY EVIDENT IN GEOSTATIONARY SATELLITE IMAGES AND THE
CONVECTIVE CLOUD PATTERN IS A LITTLE MORE SYMMETRIC THAN IT WAS
LAST NIGHT. THE INITIAL WIND SPEED IS HELD AT 85 KT...WHICH IS
SLIGHTLY HIGHER THAN DVORAK CLASSIFICATIONS FROM TAFB AND SAB. ONLY
A LITTLE WEAKENING IS FORECAST DURING THE NEXT 36 TO 48 HOURS AS
THE COMPACT HURRICANE REMAINS OVER 27 TO 28C WATERS AND IN A LOW
WIND SHEAR ENVIRONMENT. STRONG NORTHERLY SHEAR...ASSOCIATED WITH
THE OUTFLOW OF LESLIE...IS EXPECTED TO BEGIN AFFECTING MICHAEL IN 2
TO 3 DAYS AND SHOULD CAUSE A FASTER RATE OF WEAKENING. MOST OF THE
MODEL GUIDANCE SHOWS MICHAEL MERGING WITH A WARM FRONT TO THE EAST
OF LESLIE BY TUESDAY NIGHT AND BECOMING ABSORBED BY THE FRONT ON
WEDNESDAY. THE NHC INTENSITY FORECAST IS BASICALLY THE SAME AS THE
PREVIOUS ONE AND CALLS FOR MICHAEL TO LOSE TROPICAL CHARACTERISTICS
BY DAY 4.
 
THE HURRICANE HAS JOGGED TO THE NORTH RECENTLY...BUT A LONGER TERM
MOTION IS 330/4. A SLOW NORTHWESTWARD MOTION IS EXPECTED OVER THE
NEXT DAY OR TWO AS MICHAEL REMAINS IN WEAK STEERING SURROUNDED BY A
TROUGH TO ITS NORTHEAST...A RIDGE TO IS SOUTHEAST...AND A
DEVELOPING RIDGE TO ITS NORTHWEST. THE RIDGE THAT IS CURRENTLY TO
THE NORTHWEST OF MICHAEL IS EXPECTED TO STRENGTHEN AND SHIFT
EASTWARD...AND THAT WILL CAUSE THE HURRICANE TO TURN WEST-
NORTHWESTWARD IN A COUPLE OF DAYS. BY 72 HOURS...MICHAEL IS
EXPECTED TO BE ON THE WESTERN PERIPHERY OF THE RIDGE AND IN A
STRONG SOUTHERLY STEERING CURRENT...WHICH SHOULD RESULT IN A
NORTHWARD ACCELERATION. THE OFFICIAL FORECAST IS ADJUSTED SLIGHTLY
TO THE WEST OF THE PREVIOUS ONE AT DAYS 3 AND 4 TO BE IN BETTER
AGREEMENT WITH THE LATEST GFS AND ECMWF RUNS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  08/0900Z 32.2N  41.8W   85 KT 100 MPH
 12H  08/1800Z 32.6N  42.2W   80 KT  90 MPH
 24H  09/0600Z 33.1N  42.7W   80 KT  90 MPH
 36H  09/1800Z 33.5N  43.2W   80 KT  90 MPH
 48H  10/0600Z 33.9N  44.3W   75 KT  85 MPH
 72H  11/0600Z 36.7N  47.1W   60 KT  70 MPH
 96H  12/0600Z 45.0N  47.5W   50 KT  60 MPH...POST-TROPICAL
120H  13/0600Z...ABSORBED BY A FRONT
 
$$
FORECASTER CANGIALOSI
 

WTNT43 KNHC 081452
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  22
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 AM AST SAT SEP 08 2012
 
MICHAEL IS A LITTLE BETTER ORGANIZED ON SATELLITE IMAGERY WITH A
SMALL EYE THAT HAS RECENTLY WARMED AND BECOME MORE DISTINCT.   
DVORAK ESTIMATES FROM SAB AND TAFB ARE 90 KT...WHICH ALSO MATCHES
THE ADT ESTIMATE FROM CIMSS...SO THE WIND SPEED IS INCREASED TO
THAT VALUE.  THE BIGGEST NEGATIVE FACTOR FOR MICHAEL OVER THE NEXT
COUPLE OF DAYS IS PROBABLY ITS SLOW FORWARD MOTION...WHICH IS
UPWELLING SOME COOL WATER AND LIMITING ANY INTENISIFICATION.  THIS
CAN BE SEEN IN A RECENT BUOY NEAR THE CENTER THAT SHOWED AN SST OF
ABOUT 78F.  OTHERWISE...AN ENVIRONMENT OF LIGHT SHEAR AND GRADUALLY
COOLING SSTS SHOULD PROMOTE ONLY A SMALL AMOUNT OF WEAKENING DURING
THE NEXT DAY OR TWO.  AFTER THAT TIME...MOST OF THE MODELS SHOW AN
INCREASE IN NORTHERLY SHEAR...PARTIALLY RELATED TO OUTFLOW FROM
LESLIE...ALONG WITH MICHAEL MOVING OVER COOLER WATERS.  THUS A MORE
RAPID WEAKENING IS LIKELY IN A FEW DAYS...AND THE COLD WATER SHOULD
TURN MICHAEL INTO A POST-TROPICAL CYCLONE IN ABOUT 4 DAYS.  THE NHC
FORECAST IS A LITTLE HIGHER THAN THE PREVIOUS ONE FOR THE FIRST
24H...THEN IS BLENDED BACK WITH THE PREVIOUS PREDICTION AND THE
INTENSITY CONSENSUS.
 
A LONG-TERM MOTION ESTIMATE IS 325/4.  THIS GENERAL MOTION IS
EXPECTED FOR THE NEXT DAY OR SO UNTIL A HIGH PRESSURE RIDGE BUILDS
NORTH OF THE CYCLONE...WHICH SHOULD CAUSE A TURN TO THE
WEST-NORTHWEST.  THE GLOBAL MODELS ALL HAVE A STRONGER RIDGE
THAN YESTERDAY...AND EVEN SHOWING A WESTWARD MOTION OF THE HURRICANE
IN A COUPLE OF DAYS.  LATER ON...THIS HIGH SHOULD STRENGTHEN TO THE
EAST OF MICHAEL...CAUSING THE CYCLONE TO THEN TURN TO THE NORTH AND
ACCELERATE BY DAYS 3-4.  THE MODEL GUIDANCE CONTINUES TO TREND
WESTWARD...AND THE OFFICIAL FORECAST IS ADJUSTED IN THAT DIRECTION. 
MOST OF THE GLOBAL MODELS SHOW ENOUGH SEPARATION BETWEEN MICHAEL
AND LESLIE SO THAT MICHAEL IS STEERED QUICKLY TO THE NORTH INTO A
FRONTAL BOUNDARY...AND ABSORBED IN ABOUT 5 DAYS TIME.  
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  08/1500Z 32.6N  42.1W   90 KT 105 MPH
 12H  09/0000Z 33.0N  42.5W   85 KT 100 MPH
 24H  09/1200Z 33.4N  42.9W   85 KT 100 MPH
 36H  10/0000Z 33.6N  43.8W   80 KT  90 MPH
 48H  10/1200Z 33.8N  45.1W   75 KT  85 MPH
 72H  11/1200Z 38.2N  48.2W   60 KT  70 MPH
 96H  12/1200Z 48.0N  47.5W   50 KT  60 MPH...POST-TROPICAL
120H  13/1200Z...ABSORBED BY A FRONT
 
$$
FORECASTER BLAKE
 

WTNT43 KNHC 082042
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  23
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 PM AST SAT SEP 08 2012
 
MICHAEL CONTINUES TO BE A WELL-ORGANIZED HURRICANE WITH A CLEAR
EYE...PERHAPS A LITTLE LARGER THAN BEFORE...AND A FAIRLY SYMMETRIC
OUTFLOW PATTERN.   SATELLITE INTENSITY ESTIMATES ARE ABOUT THE
SAME SO THE WIND SPEED WILL REMAIN 90 KT.  MICHAEL WILL MOST
LIKELY MAINTAIN ITS STRENGTH OR SLOWLY WEAKEN DURING THE NEXT
COUPLE OF DAYS WHILE IT MOVES OVER SOMEWHAT COOLER WATERS WITH
LIGHT SHEAR.  AN INCREASE IN SHEAR IS PROBABLE IN A FEW DAYS WHEN
THE HURRICANE ENCOUNTERS OUTFLOW FROM LESLIE...ALTHOUGH THE GLOBAL
MODELS ARE NOT IN AGREEMENT IN HOW STRONG THE SHEAR WILL BE.  IN
ANY EVENT...THE SHEAR ALONG WITH MARGINAL SSTS SHOULD PROMOTE A
MORE RAPID WEAKENING OF THE CYCLONE IN ABOUT THREE DAYS.  THE
OFFICIAL FORECAST IS VERY CLOSE TO THE PREVIOUS ONE...BETWEEN THE
INTENSITY CONSENSUS AND THE LGEM MODEL.  I WOULD NOT BE SURPRISED
IF MICHAEL MAINTAINED ITS INTENSITY BETTER THAN EXPECTED OVER THE
NEXT COUPLE OF DAYS BASED ON ITS OVERACHIEVING HISTORY.
 
THE INITIAL MOTION HAS TURNED A BIT TO THE RIGHT AND IS A LITTLE
FASTER...335/5.  MICHAEL SHOULD EXECUTE A HARD LEFT TURN BY TOMORROW
AS A RIDGE BUILDS TO THE NORTH OF THE CYCLONE.  WHILE ALL MODELS
SHOW THIS CHANGE IN TRACK...THERE ARE LARGE SPEED DISAGREEMENTS THAT
MANIFEST THEMSELVES EVEN WITHIN 24H.  THESE DIFFERENCES CAUSE
MICHAEL TO EITHER COME CLOSE TO LESLIE...LIKE THE GFS...OR FOR A
MUCH SLOWER MOTION LIKE THE ECMWF SHOWS AS ONLY A MID-LATITUDE
RIDGE STEERS THE CYCLONE.  THE LATEST NHC FORECAST IS TRENDED A BIT
SLOWER AND WEST OF THE PREVIOUS FORECAST...BUT IT MUST BE
CONSIDERED AN UNCERTAIN PREDICTION.  DESPITE THE INITIAL
DISAGREEMENTS...ALL MODELS EITHER SHOW MICHAEL AS EXTRATROPICAL BY
DAY 5...OR ABSORPTION WITHIN A FRONTAL BOUNDARY.  I WILL STAY WITH
CONTINUITY AND SHOW DISSIPATION AT THE END OF THE FORECAST PERIOD.  

 
FORECAST POSITIONS AND MAX WINDS
 
INIT  08/2100Z 33.1N  42.3W   90 KT 105 MPH
 12H  09/0600Z 33.6N  42.7W   90 KT 105 MPH
 24H  09/1800Z 33.9N  43.3W   85 KT 100 MPH
 36H  10/0600Z 34.0N  44.4W   80 KT  90 MPH
 48H  10/1800Z 34.5N  45.8W   75 KT  85 MPH
 72H  11/1800Z 41.0N  48.5W   55 KT  65 MPH
 96H  12/1800Z 50.0N  44.0W   45 KT  50 MPH...POST-TROPICAL
120H  13/1800Z...ABSORBED BY A FRONT
 
$$
FORECASTER BLAKE
 

WTNT43 KNHC 090236
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  24
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 PM AST SAT SEP 08 2012
 
MICHAEL HAS MAINTAINED A WELL-DEFINED EYE DURING THE PAST FEW
HOURS...BUT THE AREAL COVERAGE OF THE COLDEST CONVECTIVE TOPS HAS
BEEN DECREASING.  BOTH SUBJECTIVE AND OBJECTIVE FINAL T-NUMBERS
HAVE COME DOWN SINCE THE PREVIOUS ADVISORY...AND THE INTENSITY IS
LOWERED TO 85 KT.  THIS IS ALSO SUPPORTED BY THE MOST RECENT CI
NUMBER GIVEN BY THE UW-CIMSS ADT.  MICHAEL COULD FLUCTUATE IN
INTENSITY DURING THE NEXT 24 HOURS SINCE ENVIRONMENTAL CONDITIONS
ARE NOT EXPECTED TO CHANGE SUBSTANTIALLY FROM THEIR CURRENT STATES.
HOWEVER...THE UPPER-LEVEL OUTFLOW FROM LESLIE COULD BEGIN TO AFFECT
MICHAEL BY 48 HOURS...AND SEA SURFACE TEMPERATURES WILL BE FALLING
TO NEARLY 20 DEGREES CELSIUS BY 72 HOURS.  THEREFORE...FASTER
WEAKENING IS FORECAST IN 2 TO 3 DAYS...AND THE INCREASINGLY
UNFAVORABLE THERMODYNAMIC CONDITIONS SHOULD CAUSE MICHAEL TO BECOME
POST-TROPICAL IN ABOUT 72 HOURS.  THE CYCLONE IS THEN FORECAST TO
BECOME ABSORBED BY A FRONT BY DAY 4...ALTHOUGH IT IS STILL UNCLEAR
IF THE CULPRIT WILL BE THE WARM FRONT TO THE EAST OF LESLIE...AS
SHOWN BY THE GFS...OR THE COLD FRONT TRAILING LESLIE...AS SHOWN BY
THE ECMWF.
 
MICHAEL HAS MAINTAINED ITS MOTION OF 335/5 KT...BUT THE HURRICANE IS
EXPECTED TO TURN WESTWARD DURING THE NEXT 24 HOURS AS A LOW-/MID-
LEVEL ANTICYCLONE BUILDS TO ITS NORTH.  THE TRACK GUIDANCE ENVELOPE
IS INDICATING A SHARPER TURN TO THE WEST THAN IT HAS IN PREVIOUS
DAYS...AND THE NEW NHC FORECAST HAS BEEN SHIFTED A LITTLE SOUTH AND
WEST OF THE PREVIOUS ONE MAINLY AT 36 AND 48 HOURS.  THIS SOLUTION
IS STILL TO THE RIGHT OF THE GFS/ECMWF/TVCA CLUSTERING AT THOSE
TIMES.  THE MODELS COME BACK TO BETTER AGREEMENT BY 72 HOURS ONCE
MICHAEL IS ACCELERATING NORTHWARD AHEAD OF AN APPROACHING MID-
LATITUDE TROUGH...EVEN THOUGH THAT IS A CASE WHERE YOU WOULD
NORMALLY EXPECT TO SEE BIGGER TIMING DIFFERENCES.

FORECAST POSITIONS AND MAX WINDS
 
INIT  09/0300Z 33.4N  42.4W   85 KT 100 MPH
 12H  09/1200Z 33.8N  42.8W   85 KT 100 MPH
 24H  10/0000Z 33.9N  43.7W   80 KT  90 MPH
 36H  10/1200Z 34.1N  45.0W   75 KT  85 MPH
 48H  11/0000Z 35.2N  46.6W   65 KT  75 MPH
 72H  12/0000Z 42.0N  47.0W   45 KT  50 MPH...POST-TROPICAL
 96H  13/0000Z...ABSORBED BY A FRONT
 
$$
FORECASTER BERG
 

WTNT43 KNHC 090848
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  25
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 AM AST SUN SEP 09 2012
 
THE EYE OF THE SMALL HURRICANE REMAINS DISTINCT AND COLD CLOUD TOPS
SURROUND THE CENTER...THOUGH THERE HAVE BEEN OCCASIONALLY BREAKS IN
THE CONVECTIVE PATTERN. RECENT GEOSTATIONARY SATELLITE AND
MICROWAVE IMAGES SUGGEST THAT THE EYEWALL IS A LITTLE WIDER THAN IT
WAS LAST NIGHT. DVORAK CLASSIFICATIONS WERE ESSENTIALLY
UNCHANGED...THEREFORE...THE THE INITIAL WIND SPEED IS HELD AT 85
KT.
 
MICHAEL STILL LIES OVER RELATIVELY WARM WATER AND IN A FAVORABLE
UPPER-LEVEL WIND PATTERN...BUT THESE CONDITIONS ARE EXPECTED TO
CHANGE OVER THE NEXT FEW DAYS. WATER VAPOR IMAGES AND SATELLITE
DERIVED WINDS SHOW STRONG NORTHERLY FLOW ALOFT...IN PART ASSOCIATED
WITH THE OUTFLOW OF LESLIE...LOCATED A FEW HUNDRED N MI TO THE WEST
OF MICHAEL. THIS FLOW IS EXPECTED TO BEGIN AFFECTING THE HURRICANE
WITHIN THE NEXT 24 HOURS...WHICH SHOULD CAUSE SOME WEAKENING. IN 2
TO 3 DAYS...THE SHIPS MODEL SHOWS NORTHERLY SHEAR INCREASING TO
NEAR 30 KT AND MICHAEL IS EXPECTED TO BE OVER COOL WATERS BY THEN.
THESE HOSTILE CONDITIONS SHOULD CAUSE A FASTER RATE OF WEAKENING
AND A TRANSITION TO A POST-TROPICAL CYCLONE. THE INTENSITY FORECAST
IS AN UPDATE OF THE PREVIOUS ONE AND IN AGREEMENT WITH MOST OF
THE GUIDANCE.
 
MICHAEL IS MOVING NORTHWESTWARD AT ABOUT 4 KT. A MID-LEVEL RIDGE IS
EXPECTED TO BUILD TO THE NORTH OF THE HURRICANE LATER TODAY AND
TONIGHT...AND THAT SHOULD CAUSE THE SYSTEM TO TURN WESTWARD.
MICHAEL IS FORECAST TO THEN GRADUALLY TURN NORTHWARD AS IT MOVES
INTO STRONG SOUTHERLY STEERING FLOW ON THE WESTERN SIDE OF THE RIDGE
TO THE EAST OF A HIGH AMPLITUDE TROUGH. THE GLOBAL MODELS SHOW
MICHAEL BECOMING ABSORBED WITHIN A FRONTAL ZONE IN 3 TO 4 DAYS. THE
TRACK FORECAST HAS BEEN NUDGED TO THE WEST AND LIES FAIRLY CLOSE TO
THE TVCA CONSENSUS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  09/0900Z 33.8N  42.7W   85 KT 100 MPH
 12H  09/1800Z 33.9N  43.5W   80 KT  90 MPH
 24H  10/0600Z 34.0N  44.8W   75 KT  85 MPH
 36H  10/1800Z 34.6N  46.6W   70 KT  80 MPH
 48H  11/0600Z 36.5N  47.9W   60 KT  70 MPH
 72H  12/0600Z 45.5N  45.5W   45 KT  50 MPH...POST-TROPICAL
 96H  13/0600Z...ABSORBED BY A FRONT
 
$$
FORECASTER CANGIALOSI
 

WTNT43 KNHC 091449
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  26
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 AM AST SUN SEP 09 2012
 
WHILE THE OVERALL SATELLITE APPEARANCE HAS NOT CHANGED MUCH THIS
MORNING...THERE SEEM TO BE SOME CHANGES OCCURRING WITHIN THE INNER
CORE OF MICHAEL.  THE EYE HAS INCREASED IN DIAMETER FROM 10 TO 25
N MI AT THE SAME TIME CLOUD TOP TEMPERATURES HAVE WARMED...POSSIBLY
INDICATIVE OF A MIXING EVENT WITHIN THE EYE.  DVORAK T-NUMBERS FROM
BOTH SATELLITE AGENCIES ARE AT 4.5 AT 1200 UTC...AND AN AVERAGE OF
RECENT ADT VALUES IS 5.2.  THE INITIAL INTENSITY IS LOWERED
SLIGHTLY TO 80 KT ON THIS ADVISORY BASED ON A BLEND OF THESE DATA
AND IN LIGHT OF THE RECENT STRUCTURAL CHANGES WITHIN THE INNER
CORE.
 
RECENT CENTER FIXES INDICATE THAT THE HURRICANE HAS TURNED TOWARD
THE WEST...AND THE INITIAL MOTION ESTIMATE IS A SLOW 275/04. GLOBAL
MODELS SHOW A POTENT SHORTWAVE TROUGH DIGGING TO THE EAST OF
MICHAEL DURING THE NEXT 24-36 HOURS. WHILE THIS FEATURE SHOULD HAVE
NO DIRECT EFFECT ON THE CYCLONE...RISING HEIGHTS IN THE WAKE OF THE
SHORTWAVE SHOULD ALLOW FOR A SLOW WESTERLY TO WEST- NORTHWESTERLY
COURSE DURING THE NEXT DAY OR SO. BY 48 HOURS... MICHAEL SHOULD
TURN NORTHWARD AND THEN NORTH-NORTHEASTWARD AT AN INCREASING
FORWARD SPEED AS IT REACHES THE FAST-PACED SOUTH-SOUTHWESTERLY FLOW
AHEAD OF A SHARP SHORTWAVE TROUGH CROSSING THE CANADIAN MARITIMES.
THE NHC TRACK FORECAST IS ADJUSTED A BIT TO THE LEFT THROUGH 48
HOURS AND SOMEWHAT TO THE EAST BY 72 HOURS...WITH THE FORECAST NEAR
THE MIDDLE OF THE GUIDANCE ENVELOPE.
 
ALTHOUGH THE WATERS ALONG THE TRACK OF MICHAEL ARE EXPECTED TO BE
WARM ENOUGH...THE CURRENT FAVORABLE ENVIRONMENT OF LIGHT SHEAR IS
ABOUT TO CHANGE.  WITHIN 24 HOURS...STRONG NORTHERLY WIND SHEAR
OVER MICHAEL IS EXPECTED TO DEVELOP AS THE CYCLONE PASSES FROM
SOUTH OF A RIDGE AXIS TO A POSITION UNDERNEATH THE OUTFLOW
ASSOCIATED WITH LESLIE.  ALTHOUGH THIS SHEAR SHOULD BE CONFINED TO
A NARROW LAYER IN THE UPPER TROPOSPHERE...IT  COULD BE OF A
MAGNITUDE THAT WOULD INDUCE A FASTER WEAKENING THAN FORECAST.  A
BRIEF REDUCTION IN SHEAR IS POSSIBLE AFTER THIS TIME BEFORE MICHAEL
ENCOUNTERS INCREASING SOUTH-SOUTHWESTERLY SHEAR ASSOCIATED WITH A
STRONG MID-LATITUDE JET.  A COMBINATION OF THE SHEAR AND RAPIDLY
DECREASING SEA SURFACE TEMPERATURES ALONG THE TRACK SHOULD MEAN
STEADY WEAKENING UNTIL THE CYCLONE BECOMES FRONTAL AROUND 72
HOURS.  THE NHC INTENSITY FORECAST IS NEARLY THE SAME AS THE
PREVIOUS ONE...AND IS CLOSE TO A BLEND OF SHIPS MODEL OUTPUT AND
THE LATEST INTENSITY CONSENSUS AIDS.
 
  
FORECAST POSITIONS AND MAX WINDS
 
INIT  09/1500Z 33.7N  43.2W   80 KT  90 MPH
 12H  10/0000Z 33.8N  43.9W   80 KT  90 MPH
 24H  10/1200Z 34.0N  45.5W   75 KT  85 MPH
 36H  11/0000Z 35.1N  47.0W   65 KT  75 MPH
 48H  11/1200Z 38.1N  47.6W   55 KT  65 MPH
 72H  12/1200Z 46.5N  44.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
 96H  13/1200Z...DISSIPATED
 
$$
FORECASTER KIMBERLAIN
 

WTNT43 KNHC 092033
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  27
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 PM AST SUN SEP 09 2012
 
THE MIXING EVENT ACTIVE WITHIN THE INNER CORE OF MICHAEL APPEARS TO
BE NEAR COMPLETION....AND A TRANSFORMATION HAS TAKEN PLACE. THE EYE
OF THE CYCLONE HAS BECOME MORE RAGGED AND CLOUD- FILLED SINCE THIS
MORNING...WITH ITS DIAMETER MEASURING 30 N MI AFTER BEING AROUND 10
N MI ABOUT 12 HOURS AGO. THE CLOUD PATTERN IS NO LONGER
SYMMETRIC...AND CLOUD TOP TEMPERATURES CONTINUE TO WARM. DVORAK
T-NUMBERS ARE UNCHANGED AT 4.5 FROM TAFB AND SAB...AND THE ADT CI
VALUE IS 5.2. THE INITIAL INTENSITY IS KEPT AT 80 KT IN AGREEMENT
WITH A BLEND OF THESE DATA.
 
MICHAEL HAS BEEN MOVING DUE WEST SINCE THIS MORNING...AND HAS
EVEN WOBBLED A BIT SOUTH OF WEST IN RECENT HOURS.  THE INITIAL
MOTION ESTIMATE...A LONGER-TERM AVERAGE...IS 270/04.  SOUTH OF A
SMALL MID-LEVEL RIDGE...MICHAEL SHOULD CONTINUE ON A SLOW WESTWARD
TO WEST-NORTHWESTWARD COURSE FOR THE NEXT 24 HOURS.  THE CYCLONE
SHOULD REACH THE WESTERN PERIPHERY OF THIS RIDGE AROUND THAT TIME
AND TURN NORTHWESTWARD. A TURN TOWARD THE NORTH AND THEN
NORTH-NORTHEAST WITH A SIGNIFICANT INCREASE IN FORWARD SPEED IS
EXPECTED IN 36-72 HOURS...AS THE SAME SHORTWAVE TROUGH CAUSING
LESLIE TO RECURVE APPROACHES MICHAEL.  THE NHC TRACK FORECAST HAS
AGAIN BEEN ADJUSTED A BIT TO THE LEFT THROUGH 48 HOURS...FOLLOWING
THE MULTI-MODEL CONSENSUS...AND TO THE RIGHT AT 72 HOURS IN BEST
AGREEMENT WITH THE GFS MODEL.

MICHAEL SHOULD LEAVE THE LOW-SHEAR ENVIRONMENT SOUTH OF THE
AFOREMENTIONED RIDGE AND BEGIN TO FEEL THE EFFECTS OF MODERATE TO
STRONG NORTH-NORTHEASTERLY SHEAR ASSOCIATED WITH THE OUTFLOW OF
LESLIE.  SINCE THE SHEAR IS FORECAST TO BE ONLY OVER A NARROW LAYER
IN THE UPPER TROPOSPHERE...AND MICHAEL WILL BE MOVING OVER ONLY
GRADUALLY DECREASING SEA SURFACE TEMPERATURES...ONLY SLOW WEAKENING
IS FORECAST DURING THE NEXT DAY OR SO.  FASTER WEAKENING IS FORECAST
BY 48 HOURS HOURS ONCE MICHAEL ENCOUNTERS A SUBSTANTIAL INCREASE IN
SOUTH-SOUTHWESTERLY SHEAR ASSOCIATED WITH A STRONG SHORTWAVE TROUGH
CROSSING THE CANADIAN MARITIMES. THE NHC INTENSITY FORECAST IS
REDUCED SLIGHTLY FROM THE PREVIOUS ONE AND IS EXCELLENT AGREEMENT
WITH THE LATEST SHIPS AND INTENSITY CONSENSUS AIDS.
 
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  09/2100Z 33.6N  43.8W   80 KT  90 MPH
 12H  10/0600Z 33.6N  44.9W   75 KT  85 MPH
 24H  10/1800Z 34.2N  46.6W   70 KT  80 MPH
 36H  11/0600Z 36.4N  47.8W   65 KT  75 MPH
 48H  11/1800Z 39.9N  47.5W   50 KT  60 MPH
 72H  12/1800Z 47.2N  40.9W   40 KT  45 MPH...POST-TROP/EXTRATROP
 96H  13/1800Z...DISSIPATED
 
$$
FORECASTER KIMBERLAIN
 

WTNT43 KNHC 100259
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  28
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 PM AST SUN SEP 09 2012
 
THE ENHANCED INFRARED SATELLITE PRESENTATION THIS EVENING INDICATES
SIGNIFICANT WEAKENING OF THE INNER CORE OF MICHAEL...WITH AN
OPENING OF THE EYE WALL IN THE NORTHWEST QUADRANT. IT APPEARS THAT
THE MUCH ANTICIPATED INCREASING NORTHERLY SHEAR IS FINALLY
BEGINNING TO AFFECT THE CYCLONE. A BLEND OF THE SUBJECTIVE AND
OBJECTIVE SATELLITE INTENSITY ESTIMATES SUPPORTS LOWERING THE
INITIAL INTENSITY TO 75 KT. THE NORTHERLY SHEAR...PRIMARILY
ASSOCIATED WITH THE OUTFLOW OF TROPICAL STORM LESLIE...SHOULD
CONTINUE TO IMPACT THE CLOUD PATTERN DURING THE NEXT 24-36 HOURS.
AFTER THAT TIME...INCREASING SOUTHWESTERLY SHEAR DOWNSTREAM FROM A
DEEP-LAYER BAROCLINIC SYSTEM AND COOLER SEAS SURFACE TEMPERATURES
SHOULD CAUSE THE CYCLONE TO WEAKEN SUBSTANTIALLY. SUBSEQUENTLY...
MICHAEL IS FORECAST TO LOSE SUFFICIENT TROPICAL CHARACTERISTICS AND
BECOME A POST-TROPICAL CYCLONE IN 48 HOURS...THEN TRANSITION TO AN
EXTRA-TROPICAL CYCLONE IN 72 HOURS. MICHAEL SHOULD ULTIMATELY
BECOME ABSORBED BY A FRONTAL SYSTEM AROUND DAY 4...OR EARLIER. THE
NHC INTENSITY FORECAST IS BASICALLY AN UPDATE OF THE PREVIOUS
ADVISORY AND IS BASED ON THE IVCN MODEL CONSENSUS.
 
THE INITIAL MOTION IS 265/5.  A MID-LEVEL RIDGE LOCATED NORTH OF
THE CYCLONE SHOULD KEEP IT ON A GENERAL WESTWARD MOTION DURING THE
NEXT 12 HOURS OR SO.  AFTERWARD...THE LARGE-SCALE MODELS SHOW
MICHAEL TURNING NORTHWESTWARD THEN NORTH-NORTHWESTWARD IN THE
WESTERN PERIPHERY OF THE AFOREMENTIONED EASTWARD-MOVING SHORTWAVE
RIDGE.  BEYOND 36 HOURS...A TURN TOWARD THE NORTH-NORTHEAST AND A
SIGNIFICANT INCREASE IN FORWARD SPEED IS FORECAST IN RESPONSE TO A
MID- TO UPPER-LEVEL TROUGH APPROACHING FROM THE ATLANTIC CANADIAN
MARITIMES.  THE OFFICIAL TRACK FORECAST IS A LITTLE TO THE LEFT OF
THE PREVIOUS ONE AND IS HEDGED TOWARD THE TVCA CONSENSUS AND THE
FLORIDA STATE SUPER ENSEMBLE.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/0300Z 33.6N  44.4W   75 KT  85 MPH
 12H  10/1200Z 33.8N  45.6W   70 KT  80 MPH
 24H  11/0000Z 34.8N  47.2W   60 KT  70 MPH
 36H  11/1200Z 37.3N  48.1W   50 KT  60 MPH
 48H  12/0000Z 40.9N  46.9W   45 KT  50 MPH...POST-TROPICAL
 72H  13/0000Z 48.0N  40.0W   35 KT  40 MPH...POST-TROP/EXTRATROP
 96H  14/0000Z...ABSORBED BY A FRONT
 
$$
FORECASTER ROBERTS
 

WTNT43 KNHC 100843
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  29
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 AM AST MON SEP 10 2012
 
ALTHOUGH DEEP CONVECTION ASSOCIATED WITH MICHAEL HAS INCREASED
RECENTLY...THE EYE APPEARS LESS DISTINCT AND IT HAS BEEN
OCCASIONALLY CLOUD FILLED. THE INITIAL WIND SPEED IS LOWERED A
LITTLE TO 70 KT...WHICH IS NEAR THE AVERAGE OF THE LATEST DVORAK
FINAL T- AND CI-NUMBERS FROM TAFB AND SAB. THE SHIPS MODEL SHOWS
ABOUT 15 KT OF NORTHERLY SHEAR AFFECTING MICHAEL CURRENTLY. THE
SHEAR IS EXPECTED TO INCREASE OVER THE NEXT DAY OR SO...WHICH
SHOULD PROMOTE ADDITIONAL WEAKENING. BY TUESDAY NIGHT...MICHAEL IS
EXPECTED TO MOVE OVER WATER TEMPERATURES WELL BELOW 26C AND BE
NEARING A COLD FRONT. THESE CONDITIONS SHOULD CAUSE CONTINUED
WEAKENING AND A TRANSITION TO A POST-TROPICAL CYCLONE. THE MODELS
ARE IN RELATIVELY GOOD AGREEMENT IN SHOWING THE POST-TROPICAL LOW
MERGING WITH THE FRONT ON WEDNESDAY. THE NHC INTENSITY FORECAST IS
NEAR THE CONSENSUS AIDS.
 
MICHAEL HAS BEEN MOVING SOUTH OF DUE WEST FOR THE PAST 12 HOURS OR
SO...AND THE LATEST INITIAL MOTION ESTIMATE IS 265/6. A TURN TO THE
WEST-NORTHWEST IS EXPECTED LATER TODAY FOLLOWED BY A FASTER
NORTHWESTWARD MOTION TONIGHT...AS MICHAEL MOVES TO THE SOUTHWESTERN
PORTION OF A MID-LEVEL RIDGE. IN 24 TO 48 HOURS...THE CYCLONE IS
EXPECTED TO BE EMBEDDED IN STRONG FLOW BETWEEN THE AFOREMENTIONED
RIDGE AND A HIGH AMPLITUDE TROUGH. THIS FLOW PATTERN SHOULD CAUSE
MICHAEL...OR THE POST-TROPICAL CYCLONE...TO ACCELERATE NORTHWARD OR
NORTH-NORTHEASTWARD UNTIL IT IS ABSORBED. THE NHC TRACK FORECAST IS
SIMILAR TO THE GFS AND ECMWF SOLUTIONS.
 
THE 34-KT AND 50-KT WIND RADII WERE ADJUSTED BASED ON AN ASCAT PASS
SHORTLY AFTER 0000 UTC.

FORECAST POSITIONS AND MAX WINDS
 
INIT  10/0900Z 33.5N  45.2W   70 KT  80 MPH
 12H  10/1800Z 34.0N  46.5W   65 KT  75 MPH
 24H  11/0600Z 36.0N  47.9W   55 KT  65 MPH
 36H  11/1800Z 39.1N  47.6W   45 KT  50 MPH
 48H  12/0600Z 43.5N  45.0W   40 KT  45 MPH...POST-TROPICAL
 72H  13/0600Z...DISSIPATED
 
$$
FORECASTER CANGIALOSI
 

WTNT43 KNHC 101450
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  30
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 AM AST MON SEP 10 2012
 
THE SATELLITE PRESENTATION OF MICHAEL HAS NOT CHANGED MUCH IN
ORGANIZATION SINCE THE LAST ADVISORY.  WHILE THE EYE HAS CLEARED
AND BECOME SOMEWHAT BETTER DEFINED...CLOUD TOP TEMPERATURES HAVE
NOT COOLED APPRECIABLY.  THE CLOUD PATTERN HAS RECENTLY BECOME MORE
SYMMETRIC...BUT THERE IS STILL EVIDENCE OF NORTHERLY SHEAR OVER THE
CYCLONE.  SINCE DVORAK T-NUMBERS FROM TAFB/SAB ARE UNCHANGED SINCE
0600 UTC...THE INITIAL INTENSITY ESTIMATE IS HELD AT 70 KT. 
WEAKENING SHOULD BEGIN IN EARNEST AS MICHAEL ENCOUNTERS INCREASING
NORTH-NORTHEASTERLY SHEAR AND SLOWLY DECREASING SEA SURFACE
TEMPERATURES DURING THE NEXT 24-36 HOURS. AFTER THAT...EVEN
COOLER WATERS AND STRONG SOUTH-SOUTHWESTERLY SHEAR SHOULD HASTEN
THE TRANSITION OF MICHAEL TO AN EXTRATROPICAL CYCLONE IN ABOUT 48
HOURS.  THE NHC INTENSITY FORECAST IS JUST A BIT LOWER THAN THE
PREVIOUS ONE...IN GOOD AGREEMENT WITH THE LATEST SHIPS OUTPUT AS
WELL AS THE INTENSITY CONSENSUS AIDS.
 
MICHAEL HAS BEEN MOVING SLIGHTLY FASTER TOWARD THE WEST...THOUGH
RECENT CENTER FIXES SUGGEST A MOTION TO THE RIGHT OF THAT HEADING
NOW. THE INITIAL MOTION ESTIMATE...REPRESENTING A LONGER-TERM
AVERAGE OF CENTER FIXES...IS 270/07.  THE CYCLONE SHOULD BE STEERED
WEST-NORTHWESTWARD AND THEN NORTHWESTWARD DURING THE NEXT 12-18
HOURS AROUND THE SOUTHWESTERN PERIPHERY OF A MID-LEVEL RIDGE NEAR
38N 46W.  BEYOND THIS TIME...A TURN TOWARD THE NORTH AND THEN
NORTH-NORTHEAST WITH SIGNIFICANT ACCELERATION IS EXPECTED.  THIS
SHOULD OCCUR AS MICHAEL BECOMES EMBEDDED IN THE FLOW BETWEEN THE
RIDGE TO ITS EAST AND A POTENT SHORTWAVE TROUGH MOVING THROUGH THE
CANADIAN MARITIMES.  WITH THE TRACK GUIDANCE IN RELATIVELY GOOD
AGREEMENT...NO SIGNIFICANT CHANGES WERE MADE TO THE PREVIOUS
FORECAST TRACK.
 
  
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/1500Z 33.6N  46.3W   70 KT  80 MPH
 12H  11/0000Z 34.8N  47.6W   60 KT  70 MPH
 24H  11/1200Z 37.5N  48.1W   50 KT  60 MPH
 36H  12/0000Z 41.2N  46.7W   45 KT  50 MPH
 48H  12/1200Z 45.9N  42.8W   40 KT  45 MPH...POST-TROP/EXTRATROP
 72H  13/1200Z 54.0N  28.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
 96H  14/1200Z...ABSORBED BY FRONT
 
$$
FORECASTER KIMBERLAIN
 

WTNT43 KNHC 102040
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  31
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 PM AST MON SEP 10 2012
 
THE EYE OF MICHAEL HAS BECOME OBSCURED AND MORE RAGGED DURING THE
PAST SEVERAL HOURS.  NORTHERLY SHEAR MAY BE INCREASING AS EVIDENCED
BY THE APPROACH OF A CIRRUS CLOUD SHIELD FROM THE WEST ASSOCIATED
WITH OUTFLOW OF LESLIE.  THE CLOUD PATTERN HAS BECOME MORE
ASYMMETRIC AS A RESULT OF THE INCREASE IN SHEAR...WITH THE BULK OF
THE CLOUDINESS AND DEEP CONVECTION IN THE SOUTHERN SEMICIRCLE.  A
BLEND OF THE LATEST DVORAK T- AND CI-NUMBERS...AS WELL AS RECENT
ADT CI VALUES...SUGGESTS THAT MICHAEL HAS WEAKENED. THE INITIAL
INTENSITY ESTIMATE IS LOWERED TO 65 KT...IN LINE WITH THESE DATA. 
NORTH-NORTHEASTERLY SHEAR AND DECREASING SEA SURFACE TEMPERATURES
ARE EXPECTED TO TAKE A TOLL ON MICHAEL DURING THE NEXT 24 TO 36
HOURS.  AS A RESULT...CONTINUED WEAKENING IS LIKELY PRIOR TO THE
CYCLONE BECOMING A FRONTAL WAVE JUST BEFORE 48 HOURS. POST-TROPICAL
MICHAEL IS FORECAST TO BE ABSORBED BY A FRONTAL SYSTEM BY 72 HOURS. 
THE NHC INTENSITY FORECAST IS REDUCED SLIGHTLY FROM THE PREVIOUS
ONE AND IS WEIGHTED TOWARD THE BETTER PERFORMING INTENSITY
CONSENSUS AIDS.
 
THE HEADING OF MICHAEL HAS BEGUN TO QUICKLY SHIFT TOWARD THE RIGHT
AND THE FORWARD SPEED HAS INCREASED SINCE THE LAST ADVISORY.  BASED
ON THE RECENT CENTER FIXES...THE INITIAL MOTION ESTIMATE IS 305/10.
MICHAEL IS ROUNDING THE SOUTHWESTERN PERIPHERY OF A MID-LEVEL HIGH
CENTERED NEAR 39N 45W...AND A TURN TOWARD THE NORTH-NORTHWEST AND
THEN THE NORTH WITH A FURTHER INCREASE IN FORWARD SPEED SHOULD OCCUR
WITHIN 24 HOURS.  AN ACCELERATION TOWARD THE NORTH-NORTHEAST
IS EXPECTED AFTER THAT AS MICHAEL BECOMES EMBEDDED IN A FAST-PACED
FLOW IN BETWEEN THE RIDGE TO ITS EAST AND A RAPIDLY ADVANCING
SHORTWAVE OVER THE CANADIAN MARITIMES.  THE NHC TRACK FORECAST IS
ESSENTIALLY AN UPDATE OF THE PREVIOUS ONE AND LIES IN BETWEEN THE
GFS AND ECMWF MODELS...VERY NEAR THE MULTI-MODEL TVCA CONSENSUS.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/2100Z 34.4N  47.6W   65 KT  75 MPH
 12H  11/0600Z 36.2N  48.3W   55 KT  65 MPH
 24H  11/1800Z 39.8N  47.7W   45 KT  50 MPH
 36H  12/0600Z 44.2N  44.8W   40 KT  45 MPH
 48H  12/1800Z 49.6N  38.5W   35 KT  40 MPH...POST-TROP/EXTRATROP
 72H  13/1800Z...ABOSORBED BY A FRONT
 
$$
FORECASTER KIMBERLAIN
 

WTNT43 KNHC 110251
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  32
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 PM AST MON SEP 10 2012
 
THE CLOUD PATTERN OF MICHAEL HAS NOT CHANGED MUCH THIS EVENING. A
RATHER ASYMMETRIC SHAPE EXISTS...SOUTHEAST-TO-NORTHWEST
ORIENTATION...WITH THE CENTER OF CIRCULATION LOCATED JUST IN THE
NORTHWESTERN EDGE OF THE -60C CLOUD TOP CANOPY. SUBJECTIVE AND
OBJECTIVE SATELLITE INTENSITY ESTIMATES SUPPORT MAINTAINING THE
CYCLONE INITIAL INTENSITY AT 65 KT. WITHIN THE NEXT 24 HOURS...AN
INHIBITING COMBINATION OF MODERATE TO STRONG NORTH-NORTHEASTERLY
SHEAR AND COOLER SEA SURFACE TEMPERATURES SHOULD RESULT IN FURTHER
WEAKENING AND CAUSE MICHAEL TO LOSE SUFFICIENT TROPICAL
CHARACTERISTICS AND BECOME A POST-TROPICAL CYCLONE. AFTERWARD...
MICHAEL IS EXPECTED TO QUICKLY TRANSITION TO AN EXTRATROPICAL
CYCLONE AS IT INTERACTS WITH THE LARGE BAROCLINIC SYSTEM. THE
LIFE-SPAN AS AN EXTRATROPICAL CYCLONE IS FORECAST TO BE BRIEF...
HOWEVER...AS THE SYSTEM BECOMES ABSORBED BY THE FRONT AT THE END OF
THE PERIOD. THE OFFICIAL INTENSITY FORECAST IS AN UPDATE OF THE
PREVIOUS ADVISORY...AND IS BASED ON A BLEND OF THE IVCN CONSENSUS
AND THE FLORIDA STATE SUPER ENSEMBLE. 
 
THE INITIAL MOTION ESTIMATE IS 345/11. A 2302 UTC SSMIS MICROWAVE
OVERPASS FROM THE NAVY FNMOC SATELLITE DATA TROPICAL CYCLONE
WEBPAGE PROVED TO BE BENEFICIAL IN DETERMINING THE 6-HOUR MOTION.
MICHAEL IS MOVING IN THE SOUTHEASTERLY MID-LEVEL FLOW PRODUCED BY A
MID-TROPOSPHERIC HIGH TO THE NORTHEAST...OVER THE NORTHERN CENTRAL
ATLANTIC. DYNAMICAL MODELS CONTINUE TO INSIST THAT THE CYCLONE WILL
TURN NORTH-NORTHEASTWARD AND ACCELERATE...WITHIN THE NEXT 24
HOURS...IN RESPONSE TO A MID- TO UPPER-LEVEL TROUGH APPROACHING
FROM THE CANADIAN MARITIMES. THROUGH THE REMAINING PORTION OF THE
FORECAST...POST-TROPICAL CYCLONE MICHAEL IS EXPECTED TO MOVE
RAPIDLY NORTHEASTWARD AHEAD OF THE AFOREMENTIONED EASTWARD MOVING
TROUGH BEFORE BECOMING ABSORBED BY THE FRONT. THE NHC FORECAST
TRACK IS NUDGED JUST A BIT TOWARD THE LEFT OF THE PREVIOUS ONE AND
IS VERY CLOSE TO THE TVCA MULTI-MODEL CONSENSUS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  11/0300Z 35.3N  48.0W   65 KT  75 MPH
 12H  11/1200Z 37.7N  48.0W   55 KT  65 MPH
 24H  12/0000Z 42.0N  46.0W   45 KT  50 MPH...POST-TROPICAL
 36H  12/1200Z 47.2N  41.6W   40 KT  45 MPH...POST-TROP/EXTRATROP
 48H  13/0000Z 52.2N  34.5W   35 KT  40 MPH...POST-TROP/EXTRATROP
 72H  14/0000Z...ABSORBED BY A FRONT
 
$$
FORECASTER ROBERTS
 

WTNT43 KNHC 110852
TCDAT3
 
TROPICAL STORM MICHAEL DISCUSSION NUMBER  33
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 AM AST TUE SEP 11 2012
 
MICHAEL IS WEAKENING QUICKLY. DEEP CONVECTION HAS DECREASED IN BOTH
INTENSITY AND COVERAGE OVER THE LAST SEVERAL HOURS...AND MICROWAVE
DATA INDICATE THAT THE LOW-LEVEL CENTER IS DISPLACED TO THE
NORTHEAST OF THE REMAINING CONVECTION. DVORAK CLASSIFICATIONS HAVE
FALLEN BY A T-NUMBER...AND MICHAEL IS DOWNGRADED TO A TROPICAL
STORM WITH A WIND SPEED OF 55 KT...WHICH COULD STILL BE GENEROUS.
ADDITIONAL WEAKENING IS FORECAST TODAY AS THE STORM MOVES OVER
SUB-26C WATERS AND REMAINS IN AN UNFAVORABLE ATMOSPHERIC
ENVIRONMENT. THE CYCLONE WILL LIKELY BECOME POST-TROPICAL TONIGHT
OR EARLY WEDNESDAY WHEN IT IS EXPECTED TO BE OVER WATER
TEMPERATURES NEAR 20C AND IN STRONG SHEAR. THE GLOBAL MODELS ARE IN
GOOD AGREEMENT IN SHOWING THE POST-TROPICAL LOW MERGING WITH A COLD
FRONT BY WEDNESDAY NIGHT. THE NHC INTENSITY FORECAST FOLLOWS THE
MODEL CONSENSUS AND THE GUIDANCE PROVIDED BY THE OCEAN PREDICTION
CENTER.
 
THE TROPICAL STORM HAS TURNED NORTHWARD AND IS MOVING
FASTER...360/16. A TURN TO THE NORTH-NORTHEAST OR NORTHEAST WITH AN
ADDITIONAL INCREASE IN FORWARD SPEED IS PREDICTED OVER THE NEXT DAY
OR SO AS MICHAEL...OR ITS POST-TROPICAL LOW...BECOMES MORE EMBEDDED
IN STRONG FLOW BETWEEN A RIDGE TO ITS EAST AND A TROUGH TO ITS
WEST. THE NHC TRACK FORECAST IS A LITTLE FASTER THAN THE PREVIOUS
ONE AND BETWEEN THE GFS AND ECMWF MODELS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  11/0900Z 37.1N  47.7W   55 KT  65 MPH
 12H  11/1800Z 40.2N  46.7W   45 KT  50 MPH
 24H  12/0600Z 45.1N  43.2W   40 KT  45 MPH...POST-TROP/EXTRATROP
 36H  12/1800Z 50.9N  36.2W   40 KT  45 MPH...POST-TROP/EXTRATROP
 48H  13/0600Z...ABSORBED BY A FRONT
 
$$
FORECASTER CANGIALOSI
 

WTNT43 KNHC 111439
TCDAT3
 
TROPICAL STORM MICHAEL DISCUSSION NUMBER  34
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
1100 AM AST TUE SEP 11 2012
 
MOST OF THE CONVECTION HAS VANISHED...AND MICHAEL CONSISTS OF A
TIGHT SWIRL OF LOW CLOUDS. GIVEN THAT MICHAEL WAS A HURRICANE...AND
WINDS TAKE TIME TO SPIN DOWN...IT IS ESTIMATED THAT THE INITIAL
INTENSITY IS 40 KNOTS. IN FACT...THIS WAS CONFIRMED BY A RECENT
ASCAT PASS A COUPLE OF HOURS AGO. SINCE THE CYCLONE IS ALREADY OVER
COOL WATERS AND EMBEDDED WITHIN STRONG SHEAR...ADDITIONAL WEAKENING
IS ANTICIPATED...AND MICHAEL IS FORECAST TO BECOME A REMNANT LOW
LATER TODAY. IT SHOULD THEN BECOME ABSORBED BY A FRONT IN ABOUT 36
HOURS.
 
THE INITIAL MOTION IS 020 DEGREES AT 20 KNOTS.  MICHAEL IS BEING
STEERED BY THE SOUTHERLY FLOW BETWEEN A WEAK SUBTROPICAL HIGH TO THE
EAST AND A STRONG TROUGH APPROACHING FROM THE WEST. THIS WILL RESULT
IN AN INCREASE IN FORWARD SPEED UNTIL THE SYSTEM BECOMES ABSORBED
BY A FRONT.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  11/1500Z 39.2N  47.2W   40 KT  45 MPH
 12H  12/0000Z 43.0N  46.0W   35 KT  40 MPH...POST-TROP/REMNT LOW
 24H  12/1200Z 48.0N  40.0W   30 KT  35 MPH...POST-TROP/EXTRATROP
 36H  13/0000Z...ABSORBED BY A FRONT
 
$$
FORECASTER AVILA
 

