000
WTPZ43 KNHC 160836
TCDEP3
 
HURRICANE CARLOTTA DISCUSSION NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP032012
200 AM PDT SAT JUN 16 2012
 
CARLOTTA IS LOCATED LESS THAN 30 N MI INLAND FROM THE COASTLINE OF
SOUTH-CENTRAL MEXICO. HOWEVER...THE HIGH MOUNTAINOUS TERRAIN IS
STEADILY TAKING ITS TOLL ON THE HURRICANE AS INDICATED BY BOTH
SATELLITE AND RADAR IMAGERY. THE PRIMARY SUPPORT FOR KEEPING
CARLOTTA AS A HURRICANE IS BASED ON EXTRAPOLATION OF THE PREVIOUS
RECON FLIGHT-LEVEL WINDS...WHICH INDICATED THAT 65- TO 70-KT
SURFACE WINDS WERE LOCATED ABOUT 40 NMI SOUTHEAST OF THE CENTER.
THIS WOULD PLACE THESE WINDS ALONG AND JUST OFFSHORE THE COAST OF
MEXICO...WHICH CORRELATES WELL WITH CONVECTIVE BANDS OCCURRING IN
THAT AREA AS NOTED IN BOTH SATELLITE AND RADAR IMAGERY.

THE INITIAL MOTION ESTIMATE IS 300/11 KT...AND IS BASED MAINLY ON A
16/0328Z AMSU EYE POSITION AND ANIMATION OF THE ACAPULCO MEXICO
RADAR DATA. THE GLOBAL AND REGIONAL MODELS CONTINUE TO BUILD A
MID-LEVEL RIDGE SOUTHWARD ACROSS NORTHERN AND CENTRAL MEXICO OVER
THE NEXT 48 HOURS...WHICH IS EXPECTED TO FORCE CARLOTTA TO SLOW
DOWN AND GRADUALLY TURN WESTWARD. STEERING CURRENTS ARE THEN
FORECAST TO COLLAPSE AS CARLOTTA BECOMES EMBEDDED WITHIN A LARGE
CYCLONIC GYRE OVER MEXICO AND THE WESTERN GULF OF MEXICO BY DAYS
3-5. THE RESULT IS THAT CARLOTTA IS EXPECTED TO MEANDER INLAND OVER
SOUTH-CENTRAL MEXICO AND STEADILY WEAKEN INTO A REMNANT LOW BY 48
HOURS OR SO. THE OFFICIAL FORECAST TRACK IS JUST AN UPDATE OF THE
PREVIOUS FORECAST TRACK AND IS SIMILAR TO THE CONSENSUS TRACK
MODELS TVCN...TVCE...AND TVCC.

ALTHOUGH HURRICANE-FORCE WINDS MAY EXIST ALONG AND JUST OFFSHORE THE 
COAST OF MEXICO...STEADY WEAKENING IS EXPECTED AND CARLOTTA SHOULD
BECOME A TROPICAL STORM LATER TODAY AND A DEPRESSION BY TONIGHT DUE
TO INTERACTION WITH THE SIERRA MADRE MOUNTAINS. ALTHOUGH ONSHORE
SOUTHERLY FLOW ON THE EAST SIDE OF CARLOTTA SHOULD CONTINUE TO
GENERATE SQUALLS WITH GUSTY WINDS FOR THE NEXT SEVERAL DAYS...THE
PRIMARY THREAT WILL BE HEAVY RAINS...ESPECIALLY OVER THE
MOUNTAINS...DUE TO THE FORECAST SLOW MOTION OF THE CYCLONE AND ITS
REMNANTS. THIS COULD RESULT IN A PROLONGED PERIOD OF HEAVY RAINS
CAUSING LIFE-THREATENING FLASH FLOODS AND MUDSLIDES ACROSS A LARGE
PORTION OF SOUTH-CENTRAL AND SOUTHEASTERN MEXICO.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  16/0900Z 16.6N  98.4W   65 KT  75 MPH...INLAND
 12H  16/1800Z 17.1N  99.0W   45 KT  50 MPH...INLAND
 24H  17/0600Z 17.6N  99.8W   30 KT  35 MPH...INLAND
 36H  17/1800Z 17.8N 100.3W   25 KT  30 MPH...INLAND
 48H  18/0600Z 17.7N 100.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  19/0600Z 17.4N 100.4W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  20/0600Z 17.4N  99.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  21/0600Z 17.4N  99.4W   20 KT  25 MPH...POST-TROP/REMNT LOW
 
$$
FORECASTER STEWART