777 
 WTNT44 KNHC 100246
 TCDAT4
  
 TROPICAL STORM HUMBERTO DISCUSSION NUMBER   6
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092013
 1100 PM AST MON SEP 09 2013
  
 RECENT MICROWAVE IMAGES AND SCATTEROMETER DATA INDICATE THAT THE
 CENTER OF HUMBERTO REMAINS NEAR THE NORTHEASTERN EDGE OF A LARGE
 MASS OF DEEP CONVECTION.  THIS SUGGESTS THAT SOME EAST-
 NORTHEASTERLY SHEAR REMAINS OVER THE CYCLONE...ALTHOUGH RECENT
 SATELLITE PICTURES SHOW THAT CIRRUS OUTFLOW IS BEGINNING TO 
 EXPAND OUTWARD OVER THE EASTERN PORTION OF THE STORM. THE ASCAT
 DATA INDICATE THAT THE MAXIMUM WINDS HAVE INCREASED TO AROUND 50
 KT...AND THAT THE AREA OF TROPICAL STORM FORCE WINDS HAS ALSO
 EXPANDED SINCE THIS MORNING.  
   
 SATELLITE CENTER FIXES OVER THE PAST 12 HOURS SUGGEST THAT HUMBERTO
 IS MOVING A LITTLE SLOWER THAN EARLIER TODAY...WITH A MOTION OF
 285/9 KT.  THE MID-LEVEL RIDGE TO THE NORTH OF THE STORM IS
 EXPECTED TO WEAKEN VERY SOON AS A COUPLE OF MID- TO UPPER-LEVEL
 LOWS MOVE SOUTHWARD OVER THE EASTERN ATLANTIC.  THIS SHOULD CAUSE
 HUMBERTO TO TURN NORTH-NORTHWESTWARD IN 24 TO 36 HOURS AND A
 GENERAL NORTHWARD MOTION IS FORECAST TO THEN CONTINUE THROUGH 72
 HOURS.  AFTER THAT TIME...THE GLOBAL MODELS INDICATE THAT THE RIDGE
 WILL REBUILD TO THE NORTHWEST OF THE AZORES AND THIS SHOULD TURN
 HUMBERTO BACK TO THE WEST-NORTHWEST BY THE END OF THE FORECAST
 PERIOD.  
 
 THE VERTICAL SHEAR CURRENTLY OVER HUMBERTO SHOULD DECREASE
 SOON...AND THIS SHOULD ALLOW FOR STEADY STRENGTHENING DURING THE
 NEXT COUPLE OF DAYS WHILE THE CYCLONE REMAINS OVER WARM WATER.  THE
 MAJORITY OF THE INTENSITY GUIDANCE BRINGS HUMBERTO TO HURRICANE
 STRENGTH WITHIN 24 HOURS...AND SO DOES THE OFFICIAL FORECAST.  THE
 NHC INTENSITY FORECAST SHOWS A SLIGHTLY HIGHER PEAK INTENSITY THAN
 THE PREVIOUS ADVISORY...BUT STILL IT IS NOT AS AGGRESSIVE AS THE
 SHIPS GUIDANCE.  AFTER 72 HOURS...THE SHEAR IS FORECAST TO BECOME
 QUITE STRONG OUT OF THE SOUTHWEST...AND THIS IS EXPECTED TO INDUCE 
 SIGNIFICANT WEAKENING. 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  10/0300Z 13.9N  25.9W   50 KT  60 MPH
  12H  10/1200Z 14.4N  27.1W   60 KT  70 MPH
  24H  11/0000Z 15.4N  28.1W   70 KT  80 MPH
  36H  11/1200Z 16.9N  28.7W   80 KT  90 MPH
  48H  12/0000Z 19.1N  29.1W   85 KT 100 MPH
  72H  13/0000Z 23.0N  30.0W   75 KT  85 MPH
  96H  14/0000Z 25.2N  32.3W   55 KT  65 MPH
 120H  15/0000Z 26.0N  36.0W   45 KT  50 MPH
  
 $$
 FORECASTER BROWN