000 WTNT41 KNHC 302041 TCDAT1 TROPICAL STORM ARLENE DISCUSSION NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012011 400 PM CDT THU JUN 30 2011 SSM/IS DATA BACK FROM THE TIME OF LANDFALL SHOWED A MID-LEVEL EYE FEATURE ABOUT 35 N MI SOUTH-SOUTHWEST OF THE LOW-LEVEL CIRCULATION CENTER. THIS CONFIRMS THAT ARLENE HAD ISSUES WITH ITS VERTICAL ALIGNMENT AS WELL AS HAVING AN ELONGATED LOW-LEVEL CIRCULATION. SINCE LANDFALL...THE LOW-LEVEL CIRCULATION HAS BECOME LESS DEFINED IN BOTH SATELLITE IMAGERY AND SURFACE OBSERVATIONS FROM MEXICO...AND THE CENTER HAS BECOME DIFFICULT TO LOCATE. THE INITIAL INTENSITY IS REDUCED TO 35 KT BASED ON ASCAT DATA BACK AT 15Z AND THE POSSIBILITY THAT TROPICAL-STORM FORCE WINDS ARE STILL PRESENT OVER WATER EAST OF THE CENTER. THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 255/6. ARLENE SHOULD CONTINUE TO MOVE GENERALLY WEST-SOUTHWESTWARD UNTIL THE CIRCULATION DISSIPATES OVER THE MOUNTAINS OF MEXICO ON FRIDAY. ARLENE IS FORECAST TO DISSIPATE OVER THE MOUNTAINS OF CENTRAL MEXICO IN 24-36 HR...AND IT MAY NOT LAST THAT LONG. SEVERAL GLOBAL MODELS CONTINUE TO SHOW A LOW PRESSURE AREA FORMING ALONG THE PACIFIC COAST OF MEXICO IN 24-48 HR...WHICH MOVES WESTWARD TO THE SOUTH OF BAJA CALIFORNIA. WHETHER THIS IS THE REMAINS OF ARLENE OR A NEW SYSTEM REMAINS SPECULATIVE. EITHER WAY... SIGNIFICANT DEVELOPMENT OF THIS SYSTEM APPEARS UNLIKELY DUE TO COLD SEA SURFACE TEMPERATURES ALONG THE EXPECTED PATH. FORECAST POSITIONS AND MAX WINDS INIT 30/2100Z 21.3N 98.3W 35 KT 40 MPH...INLAND 12H 01/0600Z 21.1N 99.3W 30 KT 35 MPH...INLAND 24H 01/1800Z 20.6N 100.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 36H 02/0600Z...DISSIPATED $$ FORECASTER BEVEN 000 WTNT41 KNHC 302041 TCDAT1 TROPICAL STORM ARLENE DISCUSSION NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012011 400 PM CDT THU JUN 30 2011 SSM/IS DATA BACK FROM THE TIME OF LANDFALL SHOWED A MID-LEVEL EYE FEATURE ABOUT 35 N MI SOUTH-SOUTHWEST OF THE LOW-LEVEL CIRCULATION CENTER. THIS CONFIRMS THAT ARLENE HAD ISSUES WITH ITS VERTICAL ALIGNMENT AS WELL AS HAVING AN ELONGATED LOW-LEVEL CIRCULATION. SINCE LANDFALL...THE LOW-LEVEL CIRCULATION HAS BECOME LESS DEFINED IN BOTH SATELLITE IMAGERY AND SURFACE OBSERVATIONS FROM MEXICO...AND THE CENTER HAS BECOME DIFFICULT TO LOCATE. THE INITIAL INTENSITY IS REDUCED TO 35 KT BASED ON ASCAT DATA BACK AT 15Z AND THE POSSIBILITY THAT TROPICAL-STORM FORCE WINDS ARE STILL PRESENT OVER WATER EAST OF THE CENTER. THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 255/6. ARLENE SHOULD CONTINUE TO MOVE GENERALLY WEST-SOUTHWESTWARD UNTIL THE CIRCULATION DISSIPATES OVER THE MOUNTAINS OF MEXICO ON FRIDAY. ARLENE IS FORECAST TO DISSIPATE OVER THE MOUNTAINS OF CENTRAL MEXICO IN 24-36 HR...AND IT MAY NOT LAST THAT LONG. SEVERAL GLOBAL MODELS CONTINUE TO SHOW A LOW PRESSURE AREA FORMING ALONG THE PACIFIC COAST OF MEXICO IN 24-48 HR...WHICH MOVES WESTWARD TO THE SOUTH OF BAJA CALIFORNIA. WHETHER THIS IS THE REMAINS OF ARLENE OR A NEW SYSTEM REMAINS SPECULATIVE. EITHER WAY... SIGNIFICANT DEVELOPMENT OF THIS SYSTEM APPEARS UNLIKELY DUE TO COLD SEA SURFACE TEMPERATURES ALONG THE EXPECTED PATH. FORECAST POSITIONS AND MAX WINDS INIT 30/2100Z 21.3N 98.3W 35 KT 40 MPH...INLAND 12H 01/0600Z 21.1N 99.3W 30 KT 35 MPH...INLAND 24H 01/1800Z 20.6N 100.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 36H 02/0600Z...DISSIPATED $$ FORECASTER BEVEN