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| #35575 (Received by flhurricane at: 4:34 PM 26.Jul.2005) TCDAT1 TROPICAL STORM FRANKLIN DISCUSSION NUMBER 22 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 5 PM EDT TUE JUL 26 2005 A BAND OF DEEP CONVECTION...WITH CLOUD TOPS OF -70C TO -80-C...HAS REDEVELOPED EAST THROUGH SOUTH OF THE STILL EXPOSED LOW-LEVEL CENTER. GIVEN THAT THIS CYCLONE HAS HAD A RECON HISTORY OF STRONGER THAN AVERAGE WINDS AT HIGHER LEVELS...I HAVE OPTED TO KEEP FRANKLIN AS A 35-KT TROPICAL STORM FOR THIS ADVISORY. THIS IS SUPPORTED BY AN 18Z REPORT OF 31 KT FROM SHIP PIBO LOCATED ABOUT 220 NMI SOUTHEAST OF THE CENTER...OR ABOUT 70 NMI SOUTH-SOUTHEAST OF BERMUDA...AND BY A TAFB DVORAK SATELLITE CURRENT INTENSITY ESTIMATE OF 35 KT. OUTFLOW REMAINS RESTRICTED NORTHWEST-NORTHEAST. THE MOTION OVER THE PAST 18 HOURS HAS BEEN A RATHER WOBBLY 020/04. FRANKLIN IS CURRENTLY COMPLETING A 30 NMI WIDE COUNTER-CLOCKWISE LOOP...BUT THE NET OVERALL MOTION HAS BEEN NORTHEASTWARD. FRANKLIN MAY WOBBLE LIKE A CHILD'S TOP TO THE NORTH OR NORTH-NORTHEAST FOR THE NEXT 24 HOURS OR SO BEFORE STEERING CURRENTS BECOME BETTER DEFINED. A STRONG SHORTWAVE TROUGH IS FORECAST TO ERODE THE MID-LEVEL RIDGE TO THE NORTH...WHICH HAS BEEN IMPEDING ANY SIGNIFICANT POLEWARD MOTION...AND GRADUALLY LIFT OUT THE CYCLONE TO THE NORTHEAST. THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE PREVIOUS ADVISORY AND IS A LITTLE EAST OF THE NHC MODEL CONSENSUS. UNFAVORABLE UPPER-LEVEL SHEAR IS EXPECTED TO PERSIST FOR ANOTHER 18-24 HOURS...SO SOME FLUCTUATIONS IN STRENGTH ARE POSSIBLE DURING THAT TIME. BY 30-48 HOURS...THE UPPER-LEVEL SHEAR IS FORECAST TO WEAKEN TO LESS THAN 10 KT AND BECOME SOUTHEASTERLY...WHICH MAY ALLOW FOR SOME MODEST INTENSIFICATION TO OCCUR BEFORE THE UPPER-LEVEL WINDS BECOME STRONG SOUTHWESTERLY AHEAD OF AN APPROACHING FRONTAL SYSTEM. BY 60 HOURS...FRANKLIN WILL ALSO BE MOVING OVER SUB-24C SSTS...WHICH SHOULD BRING ABOUT RAPID WEAKENING UNLESS THE CYCLONE GETS ABSORBED BY THE FRONTAL SYSTEM FIRST. THIS FORECAST SCENARIO IS CONSISTENT WITH THE SHIPS INTENSITY MODEL. THE 12 FT SEA HEIGHT RADIUS WAS INCREASED IN THE SOUTHEAST QUADRANT BASED ON THE 19-FT SEA HEIGHT REPORT FROM SHIP PIBO. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 26/2100Z 32.3N 68.2W 35 KT 12HR VT 27/0600Z 33.4N 67.8W 35 KT 24HR VT 27/1800Z 34.6N 67.5W 35 KT 36HR VT 28/0600Z 36.2N 67.1W 40 KT 48HR VT 28/1800Z 37.9N 66.2W 40 KT...BECOMING EXTRATROPICAL 72HR VT 29/1800Z 40.5N 62.5W 30 KT...EXTRATROPICAL 96HR VT 30/1800Z...ABSORBED BY FRONTAL SYSTEM |
