Tropical Storm CLAUDETTE
ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM CLAUDETTE DISCUSSION NUMBER 18 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT SAT JUL 12 2003 DESPITE THE PERSISTENT UNFAVORABLE SHEAR...TENACIOUS CLAUDETTE HAS BEEN ABLE TO MAINTAIN A LOW-LEVEL CIRCULATION AND IT HAS CONTINUED TO PRODUCE INTERMETTENT BURSTS OF DEEP CONVECTION. AN AIR FORCE PLANE REPORTED FLIGHT-LEVEL WINDS OF 56 KNOTS AND A MINIMUM PRESSURE OF 1003 MB...THE LOWEST PRESSURE REPORTED BY A PLANE IN TWO DAYS. HOWEVER... IT WENT BACK UP TO 1005 MB...AS WE SPEAK. THIS SUPPORTS KEEPING THE INITIAL INTENSITY AT 45 KNOTS. THERE ARE NO SIGNS AT ALL THAT SHEAR IS RELAXING AT THIS TIME...AND IN FACT... THE LOW-LEVEL CENTER IS WELL REMOVED FROM THE CONVECTION AT THIS TIME. GLOBAL MODELS NO LONGER DEVELOP AN UPPER-LEVEL ANTICYCLONE OVER CLAUDETTE. HOWEVER...THEY DO FORECAST WEAKER SOUTHWESTERLIES OVER THE STORM IN ABOUT 24 TO 36 HOURS. THIS IS IN AGREEMENT WITH THE OUTPUT OF THE SHIPS MODEL THAT DECREASES THE SHEAR FROM 20 DOWN TO 12 KNOTS BY 36 HOURS. IF CLAUDETTE SURVIVES THE NEXT 24 HOURS... SOME SLIGHT STRENGTHENING IS POSSIBLE AND THE CYCLONE COULD BE AT OR NEAR HURRICANE STRENGTH AT THE TIME OF LANDFALL. AFTER THE LITTLE JOG TO THE NORTH TODAY...CLAUDETTE IS BACK ON TRACK. 500 MB DATA AT 00Z INDICATE THAT A TROUGH PASSED TO THE NORTH EARLIER TODAY AND A RIDGE IS BEGINNING TO BUILD TO THE NORTH OF THE CYCLONE. THIS PATTERN WOULD FORCE CLAUDETTE TO MOVE ON A MORE WESTERLY TRACK. IN FACT...THE INITIAL MOTION IS ALREADY 280 DEGREES AT 7 KNOTS. ONCE CLAUDETTE BECOMES TRAPPED SOUTH OF THE DEVELOPING RIDGE IT WILL CONTINUE MOVING WESTWARD OR EVEN SOUTH OF DUE WEST...VERY SLOWLY. LANDFALL IS EXPECTED IN ABOUT 48 TO 60 HOURS AND DISSIPATION BY DAY 4. THIS IS THE SCENARIO THAT HAS BEEN CONSISTENTLY PROVIDED BY MOST OF THE GLOBAL MODELS FOR THE PAST FEW DAYS. FORECASTER AVILA FORECAST POSITIONS AND MAX WINDS INITIAL 13/0300Z 25.1N 91.9W 45 KT 12HR VT 13/1200Z 25.7N 93.0W 45 KT 24HR VT 14/0000Z 26.0N 94.0W 45 KT 36HR VT 14/1200Z 26.0N 95.2W 50 KT 48HR VT 15/0000Z 26.0N 96.5W 60 KT 72HR VT 16/0000Z 26.0N 99.0W 30 KT...INLAND 96HR VT 17/0000Z 26.0N 101.0W 25 KT...INLAND NNNN