000
WTPZ44 KNHC 240834
TCDEP4
 
TROPICAL STORM IVO DISCUSSION NUMBER   8
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092013
200 AM PDT SAT AUG 24 2013

THE STRUCTURE OF IVO HAS EVOLVED DURING THE LAST SEVERAL HOURS.
ALTHOUGH THE CLOUD PATTERN HAS GAINED CURVATURE AND BECOME MORE
SYMMETRIC...THE INTENSITY OF THE CONVECTION HAS BEEN DECREASING.
GIVEN THESE MIXED SIGNALS THE INITIAL WIND SPEED IS HELD AT 40
KT...IN AGREEMENT WITH A SHIP REPORT OF 40 KT TO THE EAST OF THE
CENTER AND THE UW-CIMSS ADT. IVO IS MOVING OVER A SHARP SEA SURFACE
TEMPERATURE GRADIENT AND IT SHOULD BE OVER WATERS COOLER THAN 26C
WITHIN THE NEXT 12 HOURS. THEREFORE...THE OPPORTUNITY FOR
ADDITIONAL STRENGTHENING IS NARROWING...AND WEAKENING IS EXPECTED
TO COMMENCE BY TONIGHT. THE CYCLONE IS FORECAST TO BECOME A REMNANT
LOW IN ABOUT 36 HOURS...WHEN IT WILL BE OVER SSTS NEAR 20C AND IN A
STABLE ENVIRONMENT.

IVO HAS TURNED TO THE NORTH-NORTHWEST...AS EXPECTED...AND HAS SPED
UP SOME...WITH AN INITIAL MOTION ESTIMATE OF 345/12. A CONTINUED
NORTH-NORTHWEST MOTION WITH A DECREASE IN FORWARD SPEED IS FORECAST
OVER THE NEXT COUPLE OF DAYS WHILE THE STORM MOVES TOWARD A
PERSISTENT WEAKNESS IN THE SUBTROPICAL RIDGE. A SIGNIFICANT SLOW
DOWN IS FORECAST BEYOND A COUPLE OF DAYS ONCE THE CYCLONE BECOMES
SHALLOW AND IS INFLUENCED BY THE LOW-LEVEL FLOW. THE LATEST MODEL
GUIDANCE HAS SHIFTED WESTWARD THIS CYCLE...AND THE NHC TRACK
FORECAST HAS BEEN ADJUSTED IN THAT DIRECTION AND IS IN GOOD
AGREEMENT WITH THE LATEST ECMWF GUIDANCE.

RAIN ASSOCIATED WITH IVO IS SPREADING OVER THE SOUTHERN BAJA
CALIFORNIA PENINSULA. THIS MOISTURE IS EXPECTED TO SPREAD NORTHWARD
ACROSS THE BAJA PENINSULA...NORTHWESTERN MEXICO...AND THE
SOUTHWESTERN UNITED STATES...INCREASING THE POSSIBILITY OF HEAVY
RAINS AND FLASH FLOODING DURING THE NEXT COUPLE OF DAYS. 

FORECAST POSITIONS AND MAX WINDS
 
INIT  24/0900Z 22.4N 112.7W   40 KT  45 MPH
 12H  24/1800Z 23.6N 113.4W   40 KT  45 MPH
 24H  25/0600Z 25.3N 114.2W   35 KT  40 MPH
 36H  25/1800Z 26.8N 115.0W   30 KT  35 MPH...POST-TROP/REMNT LOW
 48H  26/0600Z 27.6N 115.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 72H  27/0600Z 28.3N 116.2W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  28/0600Z...DISSIPATED
 
$$
FORECASTER CANGIALOSI/BRENNAN