000
WTPZ45 KNHC 110233
TCDEP5
HURRICANE NORBERT DISCUSSION NUMBER  29
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP152008
800 PM PDT FRI OCT 10 2008
 
SATELLITE IMAGES SHOW THAT NORBERT CONTINUES TO HAVE A WELL-DEFINED
EYE SURROUNDED BY COLD CLOUD-TOP TEMPERATURES IN THE EYEWALL.
RECENT MICROWAVE IMAGES NOW SHOW ONE DISTINCT EYEWALL SO THE
EYEWALL REPLACEMENT FROM YESTERDAY HAS BEEN COMPLETED. THERE HAVE
BEEN NO CHANGES TO THE SATELLITE CLASSIFICATIONS AND THE INITIAL
INTENSITY ESTIMATE WILL REMAIN 90 KT. THE CLOUD PATTERN IS A BIT
ELONGATED FROM NORTH TO SOUTH...HERALDING AN INCREASE IN SHEAR
SOON...BUT PROBABLY NOT SOON ENOUGH TO CAUSE NORBERT TO WEAKEN MUCH
BEFORE LANDFALL. A FASTER DECREASE IN STRENGTH SHOULD OCCUR
TOMORROW AFTER THE TROPICAL CYCLONE INTERACTS WITH LAND AND THE
SHEAR INCREASES MORE SIGNIFICANTLY. THIS WEAKENING MIGHT NOT BE
FAST ENOUGH TO BRING THE SYSTEM BELOW HURRICANE STRENGTH BEFORE
LANDFALL IN MAINLAND MEXICO...SO A HURRICANE WARNING HAS BEEN
ISSUED FOR THAT AREA. THE OFFICIAL FORECAST IS BASICALLY AN UPDATE
OF THE PREVIOUS FORECAST AND IS IN GOOD AGREEMENT WITH THE LGEM
MODEL.
 
THE HURRICANE APPEARS TO HAVE TURNED TOWARD THE NORTH-NORTHEAST AND
ACCLERATED A BIT TO ABOUT 10 KT.  A TURN TOWARDS THE NORTHEAST AND
INCREASE IN FORWARD SPEED SHOULD OCCUR TOMORROW DUE TO STEERING
FROM A DEEP-LAYERED TROUGH DIVING INTO THE SOUTHWESTERN UNITED
STATES.  MODEL GUIDANCE IS GENERALLY IN GOOD AGREEMENT AND THE NHC
FORECAST IS NOT APPRECIABLY DIFFERENT FROM THE PREVIOUS ONE.   AT
THE END OF THE FORECAST...THERE WON'T BE MUCH LEFT OF NORBERT BUT
THE THREAT FOR HEAVY RAINFALL...FLASH FLOODING AND MUDSLIDES COULD
BE SIGNIFICANT OVER PORTIONS OF NORTHWESTERN MEXICO AND THE
SOUTHWESTERN UNITED STATES.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      11/0300Z 22.3N 113.1W    90 KT
 12HR VT     11/1200Z 23.9N 112.3W    85 KT
 24HR VT     12/0000Z 26.3N 110.5W    70 KT
 36HR VT     12/1200Z 29.0N 108.0W    25 KT...REMNANT LOW INLAND
 48HR VT     13/0000Z...DISSIPATED
 
$$
FORECASTER BLAKE/BEVEN