000 WTPZ43 KNHC 041437 TCDEP3 TROPICAL STORM HENRIETTE DISCUSSION NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013 800 AM PDT SUN AUG 04 2013 OVERNIGHT SCATTEROMETER DATA SUGGEST THAT THE CENTER OF THE CYCLONE IS LOCATED NEAR THE NORTHEASTERN PORTION OF THE CONVECTIVE MASS. OBJECTIVE AND SUBJECTIVE DVORAK ESTIMATES ALL SUPPORT TROPICAL STORM INTENSITY...ALTHOUGH THERE IS A LARGE SPREAD IN THE ESTIMATES RANGING FROM 35 KT FROM SAB...53 KT FROM UW/CIMSS ADT...TO 55 KT FROM TAFB. GIVEN THE UNCERTAINTY IN THE EXACT CENTER LOCATION AND OVERALL STRUCTURE OF THE SYSTEM...THE INITIAL INTENSITY IS SET AT THE LOWER END OF THE DVORAK ESTIMATES. NORTHEASTERLY VERTICAL WIND SHEAR THAT IS CURRENTLY AFFECTING THE CYCLONE IS EXPECTED TO DECREASE OVER THE NEXT DAY OR SO. THIS SHOULD ALLOW HENRIETTE TO AT LEAST GRADUALLY STRENGTHEN DURING THE NEXT SEVERAL DAYS. HENRIETTE SHOULD BE TO CLOSE TO HURRICANE STRENGTH BEFORE REACHING COOLER WATERS IN 3 TO 4 DAYS. THE TROPICAL STORM CONTINUES TO MOVE WESTWARD AT 8 KT AND THIS MOTION SHOULD CONTINUE FOR ANOTHER 24 HOURS OR SO. AFTER THAT TIME...A MID- TO UPPER-LEVEL TROUGH MOVING EASTWARD ACROSS THE PACIFIC IS FORECAST TO WEAKEN THE RIDGE TO THE NORTH OF THE CYCLONE. IN RESPONSE...HENRIETTE SHOULD TURN WEST-NORTHWESTWARD. THE MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGH ABOUT THE 36 HOUR TIME PERIOD...BUT BEGIN TO DIVERGE AFTER THAT TIME. THE GFS IS ALONG THE RIGHT SIDE OF THE MODEL ENVELOPE AS IT TAKES A STRONGER AND MORE VERTICALLY DEEP CYCLONE NORTHWESTWARD. THE REMAINDER OF MODELS GENERALLY KEEP A SOMEWHAT WEAKER CYCLONE MOVING WEST- NORTHWESTWARD OR WESTWARD. THE UPDATED NHC FORECAST IS BETWEEN THESE SOLUTIONS AND IS CLOSE TO THE MULTI-MODEL CONSENSUS AND THE PREVIOUS ADVISORY. FORECAST POSITIONS AND MAX WINDS INIT 04/1500Z 12.9N 126.5W 35 KT 40 MPH 12H 05/0000Z 12.9N 127.6W 40 KT 45 MPH 24H 05/1200Z 12.9N 129.0W 45 KT 50 MPH 36H 06/0000Z 13.3N 130.4W 50 KT 60 MPH 48H 06/1200Z 14.1N 131.9W 55 KT 65 MPH 72H 07/1200Z 15.7N 135.2W 60 KT 70 MPH 96H 08/1200Z 16.5N 139.0W 55 KT 65 MPH 120H 09/1200Z 17.2N 142.5W 45 KT 50 MPH $$ FORECASTER BROWN