000 WTNT42 KNHC 201502 TCDAT2 TROPICAL STORM BERTHA DISCUSSION NUMBER 70 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008 1100 AM EDT SUN JUL 20 2008 BERTHA IS RAPIDLY LOSING TROPICAL CHARACTERISTICS. THE WIND FIELD HAS BECOME EXTREMELY ASYMMETRIC AND THE CONVECTION IS DIMINISHING NEAR THE CENTER. THUS BERTHA IS BEING DECLARED EXTRATROPICAL AND THIS IS THE LAST ADVISORY. SHIP ABCC4 AND QUIKSCAT SUGGEST THE MAXIMUM WINDS REMAIN NEAR 60 KT. A SLOW WEAKENING IS FORECAST IN LINE WITH GLOBAL MODEL GUIDANCE. THE TRACK FORECAST IS IN GOOD AGREEMENT WITH THE MODEL CONSENSUS AND SIMILAR TO THE PREVIOUS ADVISORY. FORECAST POSITIONS AND MAX WINDS INITIAL 20/1500Z 51.3N 35.7W 60 KT...EXTRATROPICAL 12HR VT 21/0000Z 55.2N 31.2W 55 KT...EXTRATROPICAL 24HR VT 21/1200Z 61.0N 24.3W 50 KT...EXTRATROPICAL 36HR VT 22/0000Z...DISSIPATED $$ FORECASTER KNABB/BLAKE