je.st
news
Tropical Depression GABRIELLE Forecast Discussion Number 4
2013-09-05 16:41:30| National Hurricane Center (Atlantic)
Issued at 1100 AM AST THU SEP 05 2013 000 WTNT42 KNHC 051441 TCDAT2 TROPICAL DEPRESSION GABRIELLE DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL072013 1100 AM AST THU SEP 05 2013 A COMBINATION OF SATELLITE...SAN JUAN DOPPLER RADAR...RAWINSONDE... AND AIRCRAFT DATA INDICATES THAT GABRIELLE HAS BECOME VERY DISORGANIZED. THE LOW-LEVEL CENTER...WHICH IS POORLY DEFINED...IS LOCATED SOUTH OF THE MONA PASSAGE ABOUT 130 N MI FROM THE MID-LEVEL CENTER THAT IS LOCATED BETWEEN PUERTO RICO AND THE VIRGIN ISLANDS. THIS STRUCTURE MAY BE DUE TO SOME WESTERLY VERTICAL WIND SHEAR... ALTHOUGH THE SHEAR APPEARS TO BE TOO LIGHT TO HAVE SUCH A DRASTIC EFFECT ON THE CYCLONE. NONE OF THE DATA CURRENTLY SUGGEST TROPICAL STORM FORCE WINDS ARE OCCURRING...SO GABRIELLE IS DOWNGRADED TO A 30-KT TROPICAL DEPRESSION. CONVECTION CONTINUES NEAR THE MID-LEVEL CENTER...SO THERE IS STILL A CHANCE OF THE LOW-LEVEL CENTER REFORMING IN THAT AREA. IF THAT DOES NOT OCCUR...GABRIELLE IS EXPECTED TO WEAKEN AS IT INTERACTS WITH THE TERRAIN OF THE DOMINICAN REPUBLIC AND ENCOUNTERS INCREASING WESTERLY SHEAR. THE REVISED INTENSITY FORECAST NOW CALLS FOR THE CYCLONE TO DEGENERATE TO A REMNANT LOW PRESSURE AREA IN 24 HOURS AND TO DISSIPATE COMPLETELY THEREAFTER. THE INITIAL MOTION IS AN UNCERTAIN 305/8. LOW-LEVEL RIDGING NORTH AND NORTHEAST OF GABRIELLE SHOULD ALLOW THIS GENERAL MOTION TO CONTINUE UNTIL THE CYCLONE DISSIPATES. IF THE SYSTEM SURVIVES LONGER THAN CURRENTLY FORECAST...THE DYNAMICAL MODELS SUGGEST IT WILL TURN NORTHWARD IN RESPONSE TO A DEVELOPING DEEP-LAYER TROUGH OVER THE WESTERN ATLANTIC. A HEAVY RAIN THREAT CONTINUES OVER PUERTO RICO AND THE VIRGIN ISLANDS. FORECAST POSITIONS AND MAX WINDS INIT 05/1500Z 17.5N 68.1W 30 KT 35 MPH 12H 06/0000Z 18.3N 68.8W 25 KT 30 MPH 24H 06/1200Z 19.6N 69.7W 20 KT 25 MPH...POST-TROP/REMNT LOW 36H 07/0000Z...DISSIPATED $$ FORECASTER BEVEN
Tags: number
discussion
tropical
depression
Category:Transportation and Logistics