351 
 WTPZ43 KNHC 310849
 TCDEP3
 HURRICANE JIMENA DISCUSSION NUMBER  11
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP132009
 200 AM PDT MON AUG 31 2009
  
 THE SMALL EYE OF JIMENA HAS BECOME A LITTLE LESS DISTINCT IN
 INFRARED SATELLITE IMAGERY.  AN EARLIER SSMIS MICROWAVE OVERPASS
 ALSO SHOWED A SOMEWHAT LESS DEFINED EYE...BUT WITH A WELL-DEFINED
 OUTER BAND.  THIS MAY BE A SIGN THAT AN EYE-WALL REPLACEMENT HAS
 STARTED...HOWEVER THERE HAVE BEEN NO RECENT MICROWAVE IMAGES TO
 CORROBORATE THIS.  DUE TO THE RECENT SATELLITE TRENDS...DVORAK
 DATA-T NUMBER HAVE DECREASED SLIGHTLY...BUT A BLEND OF THE
 OBJECTIVE AND SUBJECTIVE CURRENT INTENSITY ESTIMATES SUGGESTS
 MAINTAINING AN INITIAL INTENSITY OF 125 KT.
  
 JIMENA IS MOVING NORTHWESTWARD OR 310/7 KT.  A MID-LEVEL RIDGE
 OVER MEXICO AND AN UPPER-LEVEL LOW NEAR THE WEST COAST OF THE
 CENTRAL BAJA PENINSULA ARE THE FEATURES THAT WILL PLAY A
 ROLE IN STEERING THE HURRICANE.  THE 0000 UTC MODELS HAVE COME INTO
 BETTER AGREEMENT ON THE FUTURE TRACK OF JIMENA.  NEARLY ALL OF THE
 MODELS KEEP THE UPPER-LOW INTACT LONG ENOUGH TO TURN THE HURRICANE
 NORTH-NORTHWESTWARD.  THE OUTLIER TO THIS SOLUTION IS THE UKMET
 WHICH CONTINUES TO SHOW A WEST-NORTHWESTWARD MOTION.  THE CANADIAN
 AND ECMWF MODELS HAVE SHIFTED EASTWARD AND ARE NOW IN MUCH BETTER
 AGREEMENT WITH THE REMAINDER OF THE GUIDANCE IN PREDICTING A TRACK
 NEAR OR OVER THE BAJA PENINSULA IN A COUPLE OF DAYS.  THE NEW NHC
 TRACK FORECAST IS ESSENTIALLY AN UPDATE TO THE PREVIOUS ADVISORY...
 AND IS NEAR THE MULTI-MODEL CONSENSUS.
  
 THE HURRICANE IS EXPECTED TO REMAIN OVER VERY WARM WATER AND IN A
 LOW SHEAR ENVIRONMENT DURING THE NEXT 24 HOURS.  THE OFFICIAL
 FORECAST SHOWS LITTLE CHANGE IN STRENGTH DURING THAT TIME...HOWEVER
 FLUCTUATIONS COULD OCCUR AS THE RESULT OF AN EYEWALL REPLACEMENT.
 IN ABOUT 48 HOURS...WESTERLY SHEAR IS FORECAST TO INCREASE.  THAT
 COMBINED WITH POSSIBLE LAND INTERACTION SHOULD BEGIN TO WEAKEN
 THE HURRICANE.  THE OFFICIAL INTENSITY FORECAST IS A BLEND OF THE
 AVAILABLE GUIDANCE AND INDICATES THAT JIMENA COULD REMAIN A VERY
 DANGEROUS HURRICANE AS IT MOVES NEAR THE SOUTHERN BAJA PENINSULA.
  
 BASED ON THE CURRENT FORECAST...A HURRICANE WARNING MAY BE REQUIRED
 LATER THIS MORNING FOR A PORTION OF THE SOUTHERN BAJA PENINSULA.
 INTERESTS ELSEWHERE IN CENTRAL AND SOUTHERN BAJA CALIFORNIA AND THE
 WESTERN PORTION OF MAINLAND MEXICO SHOULD CONTINUE TO MONITOR THE
 PROGRESS OF JIMENA.  ADDITIONAL WATCHES OR WARNINGS MAY BE REQUIRED
 FOR PORTIONS OF THESE AREAS LATER TODAY.
  
 A U.S. AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT IS SCHEDULED TO
 INVESTIGATE JIMENA AROUND 1800 UTC TODAY.  DATA FROM THE AIRCRAFT
 SHOULD PROVIDE A BETTER ASSESSMENT OF THE INTENSITY AND SIZE OF THE
 HURRICANE.
   
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      31/0900Z 17.5N 107.9W   125 KT
  12HR VT     31/1800Z 18.5N 108.7W   125 KT
  24HR VT     01/0600Z 20.1N 109.8W   125 KT
  36HR VT     01/1800Z 22.1N 110.8W   115 KT
  48HR VT     02/0600Z 24.1N 111.5W   100 KT
  72HR VT     03/0600Z 27.2N 112.7W    50 KT...INLAND
  96HR VT     04/0600Z 28.5N 113.3W    30 KT...INLAND
 120HR VT     05/0600Z 29.5N 114.0W    25 KT...REMNANT LOW
  
 $$
 FORECASTER BROWN