000 WTPZ41 KNHC 171434 TCDEP1 TROPICAL DEPRESSION ALETTA DISCUSSION NUMBER 13 NWS NATIONAL HURRICANE CENTER MIAMI FL EP012012 800 AM PDT THU MAY 17 2012 DURING THE DIURNAL CONVECTIVE MAXIMUM...A NEW BURST OF SHOWERS AND THUNDERSTORMS HAS DEVELOPED JUST NORTH AND NORTHWEST OF THE CENTER OF ALETTA. THE BURST IS LIKELY TO BE TRANSIENT...AS ALETTA IS EXPERIENCING 20 KT OF SOUTH-SOUTHWESTERLY VERTICAL WIND SHEAR...AND WATER VAPOR IMAGERY SHOWS DRY AIR TO THE WEST BEING ENTRAINED INTO THE CYCLONE. BASED ON THIS COMBINATION...ALETTA IS EXPECTED TO DECAY INTO A REMNANT LOW IN 36 H OR LESS. ONE CHANGE FROM THE PREVIOUS ADVISORY IS TO ADD A 96 H POINT...AS THE LATEST DYNAMICAL MODEL RUNS SHOW THE REMNANT LOW REMAINING IDENTIFIABLE THROUGH THAT TIME. THE INITIAL MOTION IS 325/4. ALETTA IS EMBEDDED IN AN AREA OF WEAK STEERING CURRENT SOUTH OF A MID-LEVEL TROUGH OVER NORTHWESTERN MEXICO. THE TRACK GUIDANCE SUGGESTS THAT THE CYCLONE OR ITS REMNANTS SHOULD MOVE NORTHWARD AND NORTHEASTWARD DURING THE NEXT 48 H...FOLLOWED BY A TURN TOWARD THE EAST AND SOUTHEAST AS A LARGER DISTURBANCE TO THE EAST BECOMES THE MAIN STEERING MECHANISM. THE NEW FORECAST TRACK IS SIMILAR TO THE PREVIOUS TRACK. FORECAST POSITIONS AND MAX WINDS INIT 17/1500Z 12.1N 114.8W 30 KT 35 MPH 12H 18/0000Z 12.4N 115.1W 25 KT 30 MPH 24H 18/1200Z 12.8N 115.1W 25 KT 30 MPH 36H 19/0000Z 13.3N 114.8W 20 KT 25 MPH...POST-TROP/REMNT LOW 48H 19/1200Z 13.5N 114.2W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 20/1200Z 13.0N 113.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 21/1200Z 12.0N 112.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 22/1200Z...DISSIPATED $$ FORECASTER BEVEN