000
WTNT45 KNHC 101433
TCDAT5
 
TROPICAL STORM NATE DISCUSSION NUMBER  12
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL152011
1000 AM CDT SAT SEP 10 2011
 
NATE CONTINUES TO HAVE A SOMEWHAT ATYPICAL APPEARANCE...WITH A LARGE
CENTER FILLED WITH LOW CLOUDS SURROUNDED BY SOME WEAK CONVECTIVE
BANDING. DVORAK CURRENT INTENSITY ESTIMATES ARE 45 KT FROM TAFB AND
SAB...AND THAT WILL BE THE INTENSITY FOR THIS ADVISORY. ANOTHER AIR
FORCE RESERVE HURRICANE HUNTER AIRCRAFT WILL INVESTIGATE NATE THIS
AFTERNOON. GIVEN THE LACK OF AN INNER CORE...IT APPEARS THAT ONLY
GRADUAL INTENSIFICATION IS LIKELY BEFORE LANDFALL. THE OFFICIAL
FORECAST REFLECTS THIS THINKING AND IS CLOSE TO A BLEND OF THE
SHIPS AND LGEM. IT IS POSSIBLE THAT NATE COULD STILL APPROACH
HURRICANE STRENGTH BETWEEN THE 24-HOUR FORECAST POINT AND
LANDFALL...SO THE HURRICANE WATCH IS MAINTAINED AT THIS TIME. NATE
SHOULD WEAKEN RAPIDLY AFTER LANDFALL AND DISSIPATE BY 72 HOURS...
HOWEVER THE THREAT OF HEAVY RAINFALL WILL PERSIST EVEN AFTER THE
CYCLONE WEAKENS.
 
THE INITIAL MOTION ESTIMATE IS 270/05...AS NATE IS NOW BEING STEERED
BY THE SUBTROPICAL RIDGE TO THE NORTH. AS A MID-LEVEL ANTICYCLONE
STRENGTHENS OVER MEXICO...A MOTION TO THE SOUTH OF DUE WEST IS
SHOWN BY MUCH OF THE GUIDANCE BY 12 HOURS...AND THAT IS REFLECTED IN
THE OFFICIAL FORECAST. THE NEW NHC TRACK IS AN UPDATE OF THE
PREVIOUS ONE AND LIES NEAR THE MIDDLE OF THE GUIDANCE ENVELOPE.

 
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/1500Z 20.0N  94.2W   45 KT  50 MPH
 12H  11/0000Z 19.9N  95.0W   50 KT  60 MPH
 24H  11/1200Z 19.8N  96.1W   55 KT  65 MPH
 36H  12/0000Z 19.7N  97.2W   40 KT  45 MPH...INLAND
 48H  12/1200Z 19.6N  98.4W   30 KT  35 MPH...INLAND
 72H  13/1200Z...DISSIPATED
 
$$
FORECASTER BRENNAN