000 WTPZ43 KNHC 270234 TCDEP3 TROPICAL STORM COSME DISCUSSION NUMBER 15 NWS NATIONAL HURRICANE CENTER MIAMI FL EP032013 800 PM PDT WED JUN 26 2013 DEEP CONVECTION ASSOCIATED WITH COSME HAS BEEN DECREASING IN COVERAGE AND INTENSITY. AN EARLIER TRMM OVERPASS INDICATED THAT THE LOW-LEVEL CENTER OF THE CYCLONE WAS LOCATED NEAR THE EAST-SOUTHEASTERN EDGE OF THE MAIN AREA OF DEEP CONVECTION... SUGGESTING THAT THE SYSTEM WAS BEGINNING TO BECOME DECOUPLED IN THE VERTICAL. THE CURRENT INTENSITY IS ESTIMATED TO BE 45 KT IN ACCORDANCE WITH A DVORAK ESTIMATE FROM SAB. COSME WILL SOON BE MOVING OVER SUB-22C SEA SURFACE TEMPERATURES...SO CONTINUED STEADY WEAKENING IS LIKELY. THE OFFICIAL INTENSITY FORECAST IS A BLEND OF THE DSHIPS AND LGEM GUIDANCE...AND SHOWS THE SYSTEM BECOMING A REMNANT LOW IN 24 HOURS. THE INITIAL MOTION ESTIMATE IS THE SAME AS IN THE PREVIOUS ADVISORY...295/12. COSME IS EMBEDDED IN THE STEERING FLOW ON THE SOUTH SIDE OF A LARGE MID-LEVEL HIGH PRESSURE AREA. A LOW- TO MID-LEVEL RIDGE IS FORECAST BY THE GLOBAL MODELS TO PERSIST TO THE NORTH OF COSME...OR ITS REMNANTS...FOR THE NEXT SEVERAL DAYS. THE TRACK MODELS ARE IN GOOD AGREEMENT ON A TURN TOWARD THE WEST IN 24 TO 48 HOURS. IN THE LATTER PART OF THE FORECAST PERIOD...THE RIDGE IS PREDICTED TO WEAKEN SOMEWHAT...AND THIS SHOULD LEAD TO A DECREASE IN THE FORWARD SPEED OF THE CYCLONE. THE OFFICIAL TRACK FORECAST REMAINS ROUGHLY IN THE MIDDLE OF THE GUIDANCE...AND IS VERY SIMILAR TO THE PREVIOUS NHC TRACK. FORECAST POSITIONS AND MAX WINDS INIT 27/0300Z 19.6N 117.6W 45 KT 50 MPH 12H 27/1200Z 20.4N 119.7W 35 KT 40 MPH 24H 28/0000Z 21.3N 122.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 36H 28/1200Z 21.7N 125.3W 25 KT 30 MPH...POST-TROP/REMNT LOW 48H 29/0000Z 22.0N 128.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 30/0000Z 22.0N 133.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 01/0000Z 22.0N 137.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 02/0000Z 22.0N 140.0W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ FORECASTER PASCH