Hurricane CARLOTTA

ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM
HURRICANE CARLOTTA DISCUSSION NUMBER  13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP042006
800 PM PDT FRI JUL 14 2006
 
SOMEWHAT UNEXPECTEDLY...CARLOTTA HAS MADE A COMEBACK THIS EVENING. 
DEEP CONVECTION HAS INCREASED IN BOTH COVERAGE AND INTENSITY NEAR
THE CENTER...AND A CLOUD-FILLED EYE HAS DEVELOPED.  SATELLITE
INTENSITY ESTIMATES HAVE INCREASED TO 77 KT FROM TAFB...AND ARE 65
KT FROM SAB AND AFWA.  BASED ON THIS...CARLOTTA IS UPGRADED TO A
70-KT HURRICANE.  THE CYCLONE HAS FAIR TO GOOD CIRRUS OUTFLOW IN
ALL DIRECTIONS EXCEPT THE NORTHEAST WHERE IT IS POOR.

THE INITIAL MOTION IS 285/9.  CARLOTTA REMAINS ON THE SOUTH SIDE OF
A MID/UPPER-LEVEL RIDGE OVER NORTHWESTERN MEXICO...THE SOUTHWESTERN
UNITED STATES...AND THE ADJACENT PACIFIC WATERS.  THE STORM IS ALSO
APPROACHING THE NORMAL STRONG LOW-LEVEL RIDGE OVER THE NORTHEASTERN
PACIFIC.  THE LARGE-SCALE MODELS FORECAST THE UPPER-LEVEL RIDGE TO
STAY PRESENT NORTH OF CARLOTTA FOR THE NEXT SEVERAL DAYS...ALTHOUGH
THERE ARE SOME DIFFERENCES IN THE STRENGTH CAUSED BY THE HANDLING
OF AN UPPER-LEVEL LOW CURRENTLY OVER EASTERN MEXICO.  THE
UPPER-LEVEL RIDGE SHOULD TURN CARLOTTA WESTWARD OVER THE NEXT DAY
OR TWO...WITH THE LOW-LEVEL RIDGE CONTINUING THE WESTWARD MOTION AS
CARLOTTA WEAKENS OVER COOLER WATER.  HOWEVER...THE TRACK GUIDANCE
IS NOT IN GOOD AGREEMENT ON THIS SCENARIO.  AFTER ABOUT 48 HR...THE
NOGAPS CALLS FOR A WEST-NORTHWESTWARD MOTION...THE GFDL CALLS FOR A
SOUTHWARD MOTION...THE UKMET A SLOWER WEST-NORTHWESTWARD MOTION...
AND THE BAMS A FASTER WEST-SOUTHWESTWARD MOTION.  THE NEW FORECAST
TRACK COMPROMISES BETWEEN THESE EXTREMES WITH A WESTWARD MOTION OF
6-8 KT THROUGH THE FORECAST PERIOD.  THE TRACK IS ESSENTIALLY AN
UPDATE OF THE PREVIOUS TRACK.

CARLOTTA SHOULD REACH THE 26C SEA SURFACE TEMPERATURE ISOTHERM IN A
FEW HOURS AND THEN MOVE OVER PROGRESSIVELY COOLER WATER.  THE
VERTICAL WIND SHEAR IS FORECAST TO REMAIN LIGHT...SO THE INTENSITY
FORECAST CALLS FOR A GRADUAL WEAKENING THROUGH THE FORECAST PERIOD. 
SEA SURFACE TEMPERATURE ANALYSES FROM NCEP IN WASHINGTON DC SHOW A
COLD WATER EDDY AHEAD OF CARLOTTA...AND IF THE STORM PASSES OVER
THIS FEATURES IT COULD WEAKEN FASTER THAN CURRENTLY FORECAST.
 
  
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      15/0300Z 18.9N 115.4W    70 KT
 12HR VT     15/1200Z 19.2N 116.7W    60 KT
 24HR VT     16/0000Z 19.5N 118.6W    50 KT
 36HR VT     16/1200Z 19.5N 120.4W    40 KT
 48HR VT     17/0000Z 19.5N 122.0W    30 KT
 72HR VT     18/0000Z 19.5N 124.5W    25 KT...REMNANT LOW
 96HR VT     19/0000Z 19.5N 127.0W    20 KT...REMNANT LOW
120HR VT     20/0000Z 19.5N 130.0W    20 KT...REMNANT LOW
 
$$
FORECASTER BEVEN
 
NNNN