000
WTNT44 KNHC 302056
TCDAT4
 
HURRICANE NADINE DISCUSSION NUMBER  73
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL142012
500 PM AST SUN SEP 30 2012
 
SINCE THE PREVIOUS ADVISORY...THE EYE OF NADINE HAS BECOME MORE
RAGGED AND THE SURROUNDING CONVECTIVE TOPS HAVE WARMED. HOWEVER...
DVORAK CI-NUMBERS REMAIN 4.5 FROM BOTH TAFB AND SAB...AND THE
INITIAL INTENSITY REMAINS 80 KT. THE VERTICAL SHEAR IS EXPECTED TO
REMAIN LOW FOR THE NEXT DAY OR SO BEFORE INCREASING MARKEDLY FROM
THE NORTH AND NORTHWEST IN 2 TO 3 DAYS. UNTIL THAT TIME...NADINE IS
FORECAST TO WEAKEN GRADUALLY AND MAINTAIN HURRICANE STRENGTH FOR
ABOUT 48 HOURS. BY THE END OF THE FORECAST PERIOD...THE SHEAR IS
EXPECTED TO INCREASE FURTHER AND SWITCH TO SOUTHWESTERLY...AND SEA
SURFACE TEMPERATURES ALONG THE FORECAST TRACK WILL BECOME MUCH
COLDER. FASTER WEAKENING IS THEREFORE EXPECTED AT THE LATTER PART
OF THE FORECAST...AND NADINE SHOULD BECOME POST-TROPICAL IN ABOUT 
5 DAYS.

NADINE IS SLOWING DOWN AND BEGINNING ITS COUNTERCLOCKWISE TURN. THE
ESTIMATED MOTION IS 290/6...BUT THE HURRICANE WILL SOON BE SLOWING
DOWN FURTHER AND TURNING TOWARD THE SOUTH AND SOUTHEAST DURING THE
NEXT COUPLE OF DAYS. NADINE SHOULD BEGIN FEELING THE PRESENCE OF
STRONGER MID-LATITUDE WESTERLIES IN ABOUT 3 DAYS...AT WHICH TIME
THE TROPICAL CYCLONE SHOULD ACCELERATE NORTHEASTWARD AHEAD OF A
MID-/UPPER-LEVEL CUT-OFF LOW. THERE ARE STILL SOME MODEL
DIFFERENCES BY THE END OF THE FORECAST PERIOD. THE 12Z GFS SHOWS
NADINE CONTINUING A NORTHEASTWARD MOTION UNTIL IT BECOMES
POST-TROPICAL...WHILE THE 12Z ECMWF MODEL CONTINUES TO DEPICT THE
CYCLONE TURNING WESTWARD AND REVOLVING AROUND THE NORTH SIDE OF THE
DEEP-LAYER CUT-OFF LOW. THE NHC OFFICIAL FORECAST REMAINS BETWEEN
THESE TWO SCENARIOS...LYING CLOSE TO THE PREVIOUS FORECAST AND THE
FLORIDA STATE SUPERENSEMBLE.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  30/2100Z 37.2N  39.2W   80 KT  90 MPH
 12H  01/0600Z 37.0N  39.5W   75 KT  85 MPH
 24H  01/1800Z 36.2N  39.3W   70 KT  80 MPH
 36H  02/0600Z 35.7N  38.5W   70 KT  80 MPH
 48H  02/1800Z 35.5N  37.3W   65 KT  75 MPH
 72H  03/1800Z 37.0N  33.0W   55 KT  65 MPH
 96H  04/1800Z 43.5N  28.0W   50 KT  60 MPH
120H  05/1800Z 49.5N  26.5W   45 KT  50 MPH...POST-TROP/EXTRATROP
 
$$
FORECASTER BERG