000
WTNT42 KNHC 310238
TCDAT2
 
TROPICAL STORM KATIA DISCUSSION NUMBER   8
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL122011
1100 PM AST TUE AUG 30 2011
 
A SERIES OF MICROWAVE IMAGES DURING THE LATE AFTERNOON SHOWED 
THAT THE CENTER OF KATIA WAS LOCATED NEAR THE NORTHWESTERN EDGE
OF A BAND OF DEEP CONVECTION.  SINCE THAT TIME...ANOTHER BAND OF
CONVECTION HAS DEVELOPED TO THE SOUTH AND WEST OF THE CENTER AND IT
APPEARS THAT THE CYCLONE IS GRADUALLY BECOMING BETTER ORGANIZED. 
HOWEVER...THE LATEST DVORAK INTENSITY ESTIMATES WERE UNCHANGED FROM
1800 UTC...AND THE INITIAL INTENSITY REMAINS 50 KT.  KATIA IS
FORECAST TO BE IN A FAVORABLE ENVIRONMENT CHARACTERIZED BY WARM
WATER AND VERY LOW SHEAR DURING THE NEXT SEVERAL DAYS.  STEADY
STRENGTHENING IS THEREFORE EXPECTED AND THE OFFICIAL FORECAST SHOWS
KATIA BECOMING A HURRICANE IN ABOUT 24 HOURS...AND A MAJOR
HURRICANE IN 2-3 DAYS.  THE NHC FORECAST IS A BLEND OF THE VARIOUS
INTENSITY AIDS THROUGH 72 HOURS...BUT IS CLOSER TO THE MORE
AGGRESSIVE HWRF/GFDL GUIDANCE AT 96 AND 120 HOURS.
 
KATIA IS MOVING BRISKLY WEST-NORTHWESTWARD OR 285/19 KT.  KATIA
SHOULD CONTINUE ON A WEST-NORTHWEST HEADING TO THE SOUTH OF THE
SUBTROPICAL RIDGE FOR THE NEXT SEVERAL DAYS.  LATE IN THE FORECAST
PERIOD...KATIA IS EXPECTED TO SLOW DOWN AND TURN TOWARD THE
NORTHWEST AS A TROUGH OVER THE WESTERN ATLANTIC INDUCES A WEAKNESS
IN THE RIDGE.  THE UPDATED FORECAST IS VERY SIMILAR TO THE PREVIOUS
NHC TRACK THROUGH 72 HOURS...BUT IT HAS BEEN ADJUSTED TO THE RIGHT
AT DAYS 4 AND 5 TO BE IN BETTER AGREEMENT WITH THE GFS AND ECMWF
MODELS.
  
FORECAST POSITIONS AND MAX WINDS
 
INIT  31/0300Z 13.3N  37.5W   50 KT  60 MPH
 12H  31/1200Z 14.0N  40.1W   60 KT  70 MPH
 24H  01/0000Z 14.8N  43.4W   70 KT  80 MPH
 36H  01/1200Z 15.5N  46.5W   80 KT  90 MPH
 48H  02/0000Z 16.5N  49.3W   90 KT 105 MPH
 72H  03/0000Z 18.5N  54.0W  100 KT 115 MPH
 96H  04/0000Z 20.5N  57.5W  110 KT 125 MPH
120H  05/0000Z 23.0N  60.5W  110 KT 125 MPH
 
$$
FORECASTER BROWN