917 
 WTPZ42 KNHC 140310
 TCDEP2
 TROPICAL STORM ISIS DISCUSSION NUMBER  24
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 8 PM PDT MON SEP 13 2004
  
 VISIBLE ANIMATION DEPICTS THAT ISIS CONTINUES TO HAVE INTERMITTANT
 BURSTS OF CONVECTION NEAR THE CENTER. WIND SHEAR ALSO APPEARS TO BE
 LESSENING...ACCORDING TO THE UW-CIMSS ANALYSIS. WIDESPREAD
 STRATOCUMULUS INFLOW ON THE WESTERN SEMI-CIRCLE CONTINUES AND IS
 MORE THAN LIKELY THE ONLY MECHANISM THAT IS PREVENTING ISIS FROM
 INTENSIFYING. CURRENT SATELLITE INTENSITY ESTIMATES ARE 55 KT FROM
 SAB...45 KT FROM AFWA...AND 35 KT FROM TAFB. THE INITIAL INTENSITY
 WILL REMAIN AT 45 KT. SHIPS WANTS TO CONTINUE TO INTENSIFY ISIS BUT
 THE INTRUSION OF THE DRIER AIR SEEMS TO BE TAKING ITS TOLL. ISIS
 SHOULD CONTINUE TO WIND DOWN SLOWLY AND THE OFFICIAL INTENSITY
 FORECAST HOLDS THE SYSTEM INVARIANT THROUGHOUT THE FORECAST PERIOD.
 
 INITIAL MOTION IS 270/6 KT. ISIS IS SLOWING DOWN AS THE GLOBAL
 MODELS HAVE BEEN PREDICTING. A MID-LEVEL RIDGE TO THE NORTHWEST OF
 ISIS SHOULD CONTINUE TO WEAKEN AND RETROGRADE WEST IN RESPONSE TO
 AN APPROACHING MID-LATITUDE TROUGH. THROUGH THE REMAINDER OF THE
 FORECAST...ISIS SHOULD SLOW AND MEANDER AS STEERING CURRENTS
 DECREASE.  THE OFFICIAL FORECAST IS BASICALLY AN UPDATE OF THE
 PREVIOUS ADVISORY AND IS BASED ON A BLEND OF THE GFS...UKMET AND
 NOGAPS GUIDANCE.
 
 FORECASTER JARVINEN
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      14/0300Z 16.7N 129.3W    45 KT
  12HR VT     14/1200Z 16.7N 130.3W    45 KT
  24HR VT     15/0000Z 16.8N 131.2W    45 KT
  36HR VT     15/1200Z 16.8N 131.7W    45 KT
  48HR VT     16/0000Z 16.9N 132.1W    45 KT
  72HR VT     17/0000Z 17.1N 132.2W    45 KT
  96HR VT     18/0000Z 17.5N 132.2W    45 KT
 120HR VT     19/0000Z 17.4N 132.2W    45 KT
  
  
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