982 
 WTPZ43 KNHC 020900
 TCDEP3
 HURRICANE JIMENA DISCUSSION NUMBER  19
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP132009
 200 AM PDT WED SEP 02 2009
  
 THE SATELLITE PRESENTATION OF JIMENA APPEARED TO BE DETERIORATING
 SIGNIFICANTLY SEVERAL HOURS AGO...BUT RECENTLY A NEW CONVECTIVE
 BAND HAS DEVELOPED THAT WRAPS AROUND THE WESTERN SIDE OF THE
 CIRCULATION.  RECENT TRMM PASSES AT 2340 UTC AND 0612 UTC SUGGEST
 THAT A MID-LEVEL CENTER OF CIRCULATION WAS SHED OFF TOWARD THE
 NORTHEAST BUT THAT THE LOW-LEVEL CLOUD PATTERN REMAINS LARGELY
 SYMMETRIC.  DVORAK T-NUMBERS HAVE CONTINUED TO DECREASE...AND AN
 AVERAGE OF THE SUBJECTIVE AND OBJECTIVE TECHNIQUES YIELDS AN
 INITIAL INTENSITY OF 90 KT.
 
 THE 0612 UTC TRMM OVERPASS INDICATED THAT THE LOW-LEVEL CENTER HAS
 MOVED A LITTLE TO THE WEST OF THE PREVIOUS FORECAST TRACK...AND THE
 INITIAL MOTION IS ESTIMATED AT 340/11.  THE MODEL GUIDANCE IS IN
 GOOD AGREEMENT FOR THE NEXT 24 HOURS AND SHOWS THE CENTER OF JIMENA
 MOVING NORTH-NORTHWESTWARD VERY NEAR CABO SAN LAZARO.  ONLY THE
 UKMET IS AN OUTLIER BY SHOWING A MORE SUDDEN NORTHWARD TURN INLAND. 
 BEYOND 24 HOURS OR SO...THE NORTHWARD MOTION OF JIMENA IS EXPECTED
 TO BE IMPEDED BY A MID-LEVEL ANTICYCLONE LOCATED OVER THE
 SOUTHWESTERN UNITED STATES.  CONSEQUENTLY...THE MODEL ENVELOPE
 SHOWS JIMENA SLOWING DOWN CONSIDERABLY BY 36-48 HOURS FOLLOWED BY A
 SLOW WESTWARD DRIFT AT DAYS 3 AND 4.  THE NEW OFFICIAL FORECAST IS
 SLOWED DOWN AND SHIFTED SOUTHWEST FROM THE PREVIOUS TRACK AND NOW
 INDICATES A SLOW WESTWARD TURN BEYOND 48 HOURS.
 
 SEA SURFACE TEMPERATURES CONTINUE TO DECREASE AS JIMENA MOVES
 NORTH-NORTHWESTWARD PARALLEL TO THE BAJA COAST...AND THE
 THERMOCLINE ALONG THAT PART OF THE COAST IS VERY SHALLOW DUE TO
 NORMAL COASTAL UPWELLING.  COMBINED WITH POSSIBLE LAND
 INTERACTION...THIS IS EXPECTED TO CAUSE JIMENA TO CONTINUE TO
 WEAKEN OVER THE NEXT 24 HOURS.  HOWEVER...THE OFFICIAL FORECAST
 STILL SHOWS JIMENA MOVING INLAND AS A HURRICANE.  ONCE
 INLAND...WESTERLY UPPER-LEVEL WINDS ARE EXPECTED TO STRENGTHEN
 CONSIDERABLY...AND JIMENA SHOULD SPIN DOWN TO A TROPICAL DEPRESSION
 BY 48 HOURS AND A REMNANT LOW BY 72 HOURS.  THE NEW FORECAST SHOWS
 DISSIPATION BY DAY 5 SINCE MOST OF THE GLOBAL MODEL FIELDS LOSE THE
 SURFACE CIRCULATION BY THEN.
 
 INTERESTS IN THE HURRICANE WARNING AREA ARE ADVISED THAT STRONG
 WINDS WILL PRECEDE THE ARRIVAL OF THE CENTER BY SEVERAL HOURS...SO
 PREPARATIONS NEED TO BE COMPLETED VERY SOON.  REMEMBER NOT TO FOCUS
 ON THE EXACT FORECAST TRACK SINCE DANGEROUS IMPACTS EXTEND SOME
 DISTANCE FROM THE CENTER.  THE FORECAST TRACK OF JIMENA IS ALMOST
 PARALLEL TO THE COAST OF BAJA CALIFORNIA...AND SMALL DEVIATIONS
 LEFT OR RIGHT OF THE TRACK COULD RESULT IN LARGE ERRORS IN BOTH THE
 LOCATION AND TIMING OF LANDFALL.
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      02/0900Z 23.9N 111.9W    90 KT
  12HR VT     02/1800Z 25.3N 112.5W    80 KT
  24HR VT     03/0600Z 26.6N 113.0W    65 KT...ON THE BAJA COAST
  36HR VT     03/1800Z 27.4N 113.5W    45 KT...INLAND
  48HR VT     04/0600Z 27.7N 113.9W    30 KT...INLAND
  72HR VT     05/0600Z 27.7N 114.5W    25 KT...REMNANT LOW INLAND
  96HR VT     06/0600Z 27.5N 115.0W    20 KT...REMNANT LOW
 120HR VT     07/0600Z...DISSIPATED
  
 $$
 FORECASTER BERG/PASCH