000
WTPZ44 KNHC 222059
TCDEP4
 
HURRICANE DORA DISCUSSION NUMBER  18
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP042011
200 PM PDT FRI JUL 22 2011
 
THE SATELLITE SIGNATURE OF DORA HAS DEGRADED DURING THE PAST FEW
HOURS.  THE CENTER IS EMBEDDED ON THE NORTHWESTERN SIDE OF THE DEEP
CONVECTION...JUST TO THE NORTH OF A MID-LEVEL ROTATION NOTED ON
VISIBLE SATELLITE IMAGES.  THE INTENSITY IS REDUCED TO 70 KT...IN
ACCORDANCE WITH THE LATEST DVORAK ESTIMATES OF 65 AND 77 KT
FROM TAFB/SAB.  A NOAA RECONNAISSANCE AIRCRAFT JUST PASSED THROUGH
THE CENTER OF DORA A FEW MINUTES AGO...AND WILL BE IN THE STORM FOR
ANOTHER HOUR OR TWO.  THEY HAVE NOT COMPLETED ENOUGH OF THE PATTERN
TO ESTABLISH WHETHER DORA IS STILL A HURRICANE.
 
THE SYSTEM IS CROSSING THE 26C ISOTHERM INTO MUCH COOLER WATERS.
WITH SOME NORTHEASTERLY SHEAR AND A MORE STABLE AIR MASS
EXPECTED...A CONTINUED WEAKENING OF DORA IS FORECAST. DORA SHOULD
WEAKEN INTO A TROPICAL STORM WITHIN THE NEXT TWELVE HOURS...AND
COULD BECOME A TROPICAL DEPRESSION TOMORROW. REMNANT LOW STATUS IS
LIKELY IN 36 TO 48 HOURS OVER THE COLD WATERS WEST OF BAJA.
 
AN UNCERTAIN ESTIMATE OF INITIAL MOTION IS 310/7.  MODELS ARE IN
GOOD AGREEMENT ON THIS GENERAL TRACK AND SPEED FOR THE NEXT DAY OR
SO.  THEREAFTER...SOME OF THE MODELS WANT TO BEND DORA...OR OR ITS
REMNANTS...TOWARD BAJA DUE TO A TEMPORARY WEAKNESS IN THE
RIDGE...WHILE OTHERS BASICALLY CONTINUE THE NORTHWESTWARD TRACK.
THE GLOBAL MODELS HAVE HAD AN EXCELLENT PERFORMANCE FOR THIS
STORM...AND SINCE THESE MODELS KEEP DORA AWAY FROM THE
COAST...THE NEW NHC FORECAST WILL CONTINUE THE IDEA OF A
NORTHWESTWARD TRACK UNTIL DISSIPATION.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/2100Z 19.8N 109.9W   70 KT  80 MPH
 12H  23/0600Z 20.5N 110.8W   55 KT  65 MPH
 24H  23/1800Z 21.4N 112.0W   40 KT  45 MPH
 36H  24/0600Z 22.4N 113.2W   30 KT  35 MPH
 48H  24/1800Z 23.5N 114.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  25/1800Z 25.5N 117.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  26/1800Z 27.0N 118.5W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  27/1800Z...DISSIPATED
 
$$
FORECASTER BLAKE/FRANKLIN