986 
 WTPZ44 KNHC 121444
 TCDEP4
 TROPICAL STORM HERNAN DISCUSSION NUMBER  24
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP092008
 800 AM PDT TUE AUG 12 2008
  
 HERNAN HAS VERY LITTLE DEEP CONVECTION NOW THAT IT IS OVER SEA
 SURFACE TEMPERATURES NEAR 23C. AN AVERAGE OF THE TAFB AND SAB
 SATELLITE CLASSIFICATIONS PROVIDES AN ESTIMATE OF 45 KT AND THE
 MOST RECENT ADT IS NOW DOWN TO 30 KT. GIVEN THE DEGRADATION OF THE
 CLOUD PATTERN...THE INITIAL INTENSITY IS SET AS 40 KT AS A
 COMPROMISE OF THE SUBJECTIVE AND OBJECTIVE TECHNIQUES. SINCE IT IS
 UNLIKELY THAT HERNAN WILL BE ABLE TO GENERATE PERSISTENT CONVECTION
 OVER THE COOLER WATERS...THE CYCLONE IS EXPECTED TO WEAKEN TO A
 TROPICAL DEPRESSION LATER TODAY. THE NEW FORECAST SHOWS HERNAN
 DISSIPATING INTO AN OPEN WAVE WITHIN THE TRADE WIND BELT SOUTHEAST
 OF HAWAII BY DAY 5...IF NOT SOONER...IN LINE WITH THE GLOBAL MODEL
 GUIDANCE.
  
 THE INITIAL MOTION IS JUST SOUTH OF DUE WEST AT 260/8. THE
 SHORT-TERM MOTION WILL BE DICTATED BY A MID-LEVEL RIDGE AXIS
 EXTENDING SOUTHWEST OF SOUTHERN CALIFORNIA DIRECTLY TOWARDS
 HERNAN...WHICH WILL FORCE A MORE WEST-SOUTHWESTWARD MOTION. ONCE
 HERNAN WEAKENS TO A REMNANT LOW...IT IS EXPECTED TO TURN WEST WITH
 AN INCREASE IN SPEED AS IT IS STEERED BY THE LOW-LEVEL SUBTROPICAL
 RIDGE.
  
 
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      12/1500Z 18.3N 133.6W    40 KT
  12HR VT     13/0000Z 18.1N 134.7W    30 KT
  24HR VT     13/1200Z 17.7N 136.2W    30 KT
  36HR VT     14/0000Z 17.2N 137.7W    25 KT...REMNANT LOW
  48HR VT     14/1200Z 16.7N 139.2W    25 KT...REMNANT LOW
  72HR VT     15/1200Z 15.5N 143.5W    20 KT...REMNANT LOW
  96HR VT     16/1200Z 15.0N 148.0W    20 KT...REMNANT LOW
 120HR VT     17/1200Z...DISSIPATED
  
 $$
 FORECASTER BERG/BROWN