000 WTNT42 KNHC 200257 TCDAT2 TROPICAL STORM BERTHA DISCUSSION NUMBER 68 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008 1100 PM EDT SAT JUL 19 2008 THE SATELLITE PRESENTATION OF BERTHA HAS DEGRADED OVER THE PAST FEW HOURS...WITH THE CONVECTION BECOMING LESS SYMMETRIC AND BEGINNING TO WARM. THE EYE THAT WAS VISIBLE SIX HOURS AGO IS GONE. DVORAK T NUMBERS ARE DECREASING...AND THE INITIAL INTENSITY IS LOWERED TO 60 KT. FORECAST TO BE OVER 11C WATERS IN ABOUT 18 HOURS...BERTHA SHOULD NOT BE ABLE TO MAINTAIN TROPICAL CHARACTERISTICS BEYOND MIDDAY TOMORROW. DESPITE THE TRANSITION...THE WINDS WILL PROBABLY NOT FALL OFF VERY FAST...AND BERTHA WILL BE A LARGE AND POWERFUL EXTRATROPICAL CYCLONE FOR TWO TO THREE DAYS UNTIL IT IS ABSORBED BY OR MERGES WITH ANOTHER SYSTEM CROSSING CANADA. THE INITIAL MOTION IS 040/21...ABOUT THE SAME AS BEFORE. AN INCREASE IN FORWARD SPEED IS FORECAST...IN CLOSE AGREEMENT WITH A TIGHTLY-PACKED MODEL CONSENSUS AND THE PREVIOUS ADVISORY. FORECAST POSITIONS AND MAX WINDS INITIAL 20/0300Z 45.7N 41.8W 60 KT 12HR VT 20/1200Z 49.8N 37.4W 55 KT 24HR VT 21/0000Z 55.0N 31.4W 55 KT...EXTRATROPICAL 36HR VT 21/1200Z 60.1N 24.8W 50 KT...EXTRATROPICAL 48HR VT 22/0000Z 64.0N 18.0W 50 KT...EXTRATROPICAL 72HR VT 23/0000Z...ABSORBED $$ FORECASTER FRANKLIN