525 
 WTPZ45 KNHC 092033
 TCDEP5
 HURRICANE NORBERT DISCUSSION NUMBER  24
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP152008
 200 PM PDT THU OCT 09 2008
  
 SOMETIMES APPEARANCES ARE NOT WHAT THEY SEEM.  ALTHOUGH SATELLITE
 ESTIMATES YIELD A MAXIMUM INTENSITY OF 90-100 KT...THE AIR FORCE
 HURRICANE HUNTER FLYING THROUGH NORBERT FOUND WINDS THAT WERE MUCH
 LOWER.  THE MAXIMUM FLIGHT LEVEL WIND MEASURED WAS 83 KT WITHIN THE
 OUTER EYEWALL IN THE NORTHEAST QUADRANT WHILE THE SFMR ONLY
 INDICATED WINDS NEAR 65 KT.  THE INITIAL INTENSITY IS LOWERED TO 80
 KT...BUT THIS IS LIKELY GENEROUS.  DROPSONDE DATA INDICATE THAT
 THERE MIGHT BE A STABLE LAYER BETWEEN 700 AND 800 MB THAT IS
 PREVENTING VERTICAL MIXING OF THE STRONG WINDS FROM FLIGHT LEVEL.
  
 THE OFFICIAL INTENSITY FORECAST HAS BEEN ADJUSTED DOWNWARD TO
 ACCOUNT FOR THE LOWER INITIAL WIND SPEED.  SINCE SEA SURFACE
 TEMPERATURES WILL REMAIN WARM ALONG THE FORECAST TRACK UP UNTIL THE
 BAJA COAST...ONLY SLOW WEAKENING IS EXPECTED DURING THE FIRST 24
 HOURS BASED ON RECENT TRENDS.  THEREAFTER...VERTICAL SHEAR
 INCREASES SUBSTANTIALLY...AND NORBERT WILL LIKELY WEAKEN A LITTLE
 FASTER.  THE 48-HOUR FORECAST POINT JUST OFFSHORE THE BAJA
 PENINSULA STILL INDICATES NORBERT AS A HURRICANE FOR CONTINUITY
 ALTHOUGH IT IS POSSIBLE THAT THE CYCLONE COULD HAVE WEAKENED TO A
 TROPICAL STORM BY THEN.  ONCE NORBERT REACHES MAINLAND MEXICO...THE
 LOW-LEVEL CIRCULATION IS NOT EXPECTED TO SURVIVE THE RUGGED TERRAIN
 OF THE SIERRA MADRES IN MEXICO SO NO FORECAST POINTS ARE GIVEN
 BEYOND 72 HOURS.  STILL...THE MID-LEVEL REMNANTS AND ASSOCIATED
 HEAVY RAINFALL ARE EXPECTED TO MOVE NORTHEASTWARD AND AFFECT
 PORTIONS OF NORTHERN MEXICO AND THE SOUTHWESTERN AND SOUTH-CENTRAL
 UNITED STATES THROUGH DAY 4 AND 5.
  
 NORBERT CONTINUES TO WOBBLE AND HAS SLOWED DOWN TO A MOTION OF
 320/4.  THE TRACK MODEL GUIDANCE HAS NOT CHANGED APPRECIABLY SINCE
 THIS MORNING AND CONTINUES TO SHOW NORBERT MOVING NORTH THEN
 NORTH-NORTHEAST TOWARDS THE BAJA PENINSULA IN RESPONSE TO A DEEP
 MID-LATITUDE TROUGH OVER THE WESTERN UNITED STATES.  THE GFS
 REMAINS THE ONLY MODEL TO SHEAR THE SYSTEM SO MUCH THAT THE
 LOW-LEVEL CIRCULATION IS LEFT TO MEANDER OFFSHORE AND NOT MOVE INTO
 MEXICO.
  
 WATCHES ARE NOT YET NEEDED FOR THE BAJA COAST SINCE NORBERT HAS
 SLOWED DOWN...BUT THEY MAY BE REQUIRED THIS EVENING.
 
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      09/2100Z 18.3N 112.9W    80 KT
  12HR VT     10/0600Z 18.9N 113.5W    80 KT
  24HR VT     10/1800Z 20.5N 113.7W    75 KT
  36HR VT     11/0600Z 22.1N 113.3W    70 KT
  48HR VT     11/1800Z 24.1N 111.8W    65 KT
  72HR VT     12/1800Z 27.5N 109.0W    30 KT...INLAND
  96HR VT     13/1800Z...DISSIPATED INLAND
  
 $$
 FORECASTER BERG