|
|
|||||||
TROPICAL STORM FRANKLIN DISCUSSION NUMBER 20... CORRECTED NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 5 AM EDT TUE JUL 26 2005 ...CORRECTED TO DENOTE ABSORBED BY FRONTAL ZONE IN TABLE... THE LOW-LEVEL CENTER THAT HAD YESTERDAY BEEN EXPOSED HAS REMAINED INVOLVED WITH THE CONVECTION OVERNIGHT. DESPITE WHAT COULD OTHERWISE REFLECT INCREASED ORGANIZATION... FRANKLIN HAS NOT TAKEN ADVANTAGE OF THE DIURNAL CONVECTIVE MAXIMUM PERIOD... AND CLOUD TOPS HAVE BEEN STEADILY WARMING. INCREASING NORTHERLY VERTICAL WIND SHEAR AND A FAIRLY DRY ENVIRONMENT ARE TAKING THEIR TOLL ON THE TROPICAL STORM. THE ADVISORY INTENSITY WILL REMAIN 35 KT... AS SUPPORTED BY 06Z DVORAK INTENSITY ESTIMATES OF 30-35 KT... BUT CONVECTION WILL NEED TO REDEVELOP SOON IF THAT INTENSITY IS TO BE MAINTAINED FOR MUCH LONGER. FURTHER INTENSIFICATION SEEMS UNLIKELY... AND FRANKLIN MAY NOT REMAIN A TROPICAL STORM FOR AS LONG AS SHOWN IN THE OFFICIAL FORECAST. A MID-LATITUDE SHORTWAVE TROUGH HAS PASSED BY WELL TO THE NORTH OF FRANKLIN...LEAVING THE TROPICAL STORM WITHIN AN ENVIRONMENT OF WEAK STEERING. THE ANTICIPATED DECREASE IN FORWARD SPEED AND THE TURN TO THE NORTH-NORTHEAST HAVE BOTH OCCURRED... PERHAPS EVEN A LITTLE SOONER THAN EXPECTED... AND THE INITIAL MOTION ESTIMATE IS NOW 020/4. THIS SLOW GENERAL NORTHWARD MOTION MIGHT NOT CHANGE MUCH UNTIL THE NEXT STRONGER TROUGH AND ATTENDANT COLD FRONT APPROACH THE EAST COAST OF THE UNITED STATES. DYNAMICAL MODELS AGREE THAT THIS FEATURE WILL ACCELERATE FRANKLIN TO THE NORTHEAST BEGINNING IN ABOUT 36 HOURS... ALTHOUGH MOST OF THE MODELS HAVE SHIFTED A LITTLE TO THE WEST COMPARED TO EARLIER. AS A RESULT OF THIS AND THE INITIAL MOTION... THE OFFICIAL FORECAST HAS BEEN SHIFTED SLIGHTLY TO THE WEST OF THE PREVIOUS ADVISORY BUT REMAINS ON THE RIGHT SIDE OF THE DYNAMICAL MODEL SUITE. ON THIS TRACK FRANKLIN IS EXPECTED TO BECOME ABSORBED BY THE APPROACHING FRONTAL ZONE IN 3 TO 4 DAYS. |