000
WTNT42 KNHC 162037
TCDAT2
 
HURRICANE RAFAEL DISCUSSION NUMBER  17
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL172012
500 PM AST TUE OCT 16 2012
 
THE SATELLITE APPEARANCE OF RAFAEL HAS RECENTLY TRANSITIONED FROM A
CENTRAL DENSE OVERCAST TO AN EYE PATTERN...WITH A RECENT MICROWAVE
PASS SHOWING A SOLID INNER CORE.  THIS WOULD NORMALLY SUGGEST SOME
STRENGTHENING...BUT THE AIR FORCE RESERVE HURRICANE HUNTERS
REPORTED THAT FLIGHT-LEVEL AND SFMR WINDS HAD COME DOWN A BIT
DURING THE PAST FEW HOURS.  THE PLANE DATA SUGGEST AN INITIAL
INTENSITY OF ABOUT 75 KT...WITH A LITTLE HIGHER UNCERTAINTY THAN
AVERAGE GIVEN THE RECENT SATELLITE TREND.  A NOAA AIRCRAFT WILL BE
IN THE AREA THIS EVENING FOR ANOTHER LOOK AT THE INTENSITY. 
HOWEVER...SLOW WEAKENING SEEMS LIKE THE BEST BET DUE TO GRADUALLY
COOLING WATERS AND INCREASING SHEAR.  THE NHC INTENSITY FORECAST IS
AN UPDATE OF THE PREVIOUS ONE...NEAR THE LGEM MODEL BUT A BIT BELOW
THE INTENSITY CONSENSUS.  GLOBAL MODELS SUGGESTS EXTRATROPICAL
TRANSITION BETWEEN 24-36H DUE TO INTERACTION OF RAFAEL WITH A COLD
FRONT AND AN UPPER-LEVEL TROUGH.
 
AIRCRAFT FIXES SHOW THAT RAFAEL HAS RECENTLY BEEN MOVING A BIT LEFT
OF THE PREVIOUS ESTIMATE...BUT A LONGER-TERM ESTIMATE IS 020/23. 
THERE HAS BEEN NO CHANGE TO PREDICTED STEERING FLOW WITH THE
HURRICANE MOVING BETWEEN A RIDGE OVER THE CENTRAL ATLANTIC AND A
TROUGH OVER THE NORTHWESTERN ATLANTIC.  THIS SHOULD CAUSE RAFAEL TO
TURN TOWARD THE NORTHEAST BY WEDNESDAY AND TO MOVE FASTER.  MODEL
GUIDANCE IS WELL CLUSTERED ON THIS TRACK...AND EVEN THE SPEED
DIFFERENCES ARE LESS NOTICEABLE THAN ON THE PREVIOUS FORECAST
CYCLE.  THE NHC FORECAST IS ADJUSTED WESTWARD TOWARD THE
CONSENSUS...BUT STILL LIES ON THE SPEEDIER SIDE OF THE GUIDANCE FOR
THE FIRST 48 HOURS OR SO.  AFTERWARD...MOST OF THE GLOBAL MODELS
SUGGEST THAT POST-TROPICAL RAFAEL WILL COMPLETE A LARGE CYCLONIC
LOOP OVER THE NORTHEASTERN ATLANTIC. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  16/2100Z 30.6N  63.8W   75 KT  85 MPH
 12H  17/0600Z 34.0N  61.6W   70 KT  80 MPH
 24H  17/1800Z 38.8N  57.5W   65 KT  75 MPH
 36H  18/0600Z 43.1N  50.3W   60 KT  70 MPH...POST-TROP/EXTRATROP
 48H  18/1800Z 46.6N  40.8W   60 KT  70 MPH...POST-TROP/EXTRATROP
 72H  19/1800Z 52.5N  29.5W   55 KT  65 MPH...POST-TROP/EXTRATROP
 96H  20/1800Z 50.5N  34.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
120H  21/1800Z 44.0N  30.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
 
$$
FORECASTER BLAKE