000 WTPZ43 KNHC 052034 TCDEP3 TROPICAL STORM HENRIETTE DISCUSSION NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013 200 PM PDT MON AUG 05 2013 THE SMALL TROPICAL CYCLONE CONTINUES TO STRENGTHEN THIS AFTERNOON. VISIBLE SATELLITE IMAGES SHOW A CENTRAL DENSE OVERCAST FEATURE... WITH RECENT HINTS OF AN EYE. AN EARLIER 1414 UTC SSMIS MICROWAVE IMAGE REVEALED A MID-LEVEL EYE WITH A FAIRLY WELL-DEFINED LOW-LEVEL RING. DVORAK INTENSITY ESTIMATES FROM BOTH TAFB AND SAB SUPPORT AN INITIAL INTENSITY OF 55 KT. LOW SHEAR AND WARM WATERS AHEAD OF HENRIETTE DURING THE NEXT DAY OR SO SHOULD ALLOW FOR CONTINUED INTENSIFICATION...AND THE TROPICAL CYCLONE IS FORECAST TO BECOME A HURRICANE TONIGHT OR EARLY TUESDAY. IN 24 TO 36 HOURS...HENRIETTE WILL BE CROSSING A TONGUE OF COOLER SSTS THAT WILL LIKELY SLOW OR HALT THE STRENGTHENING. LATER IN THE PERIOD... COOLER WATERS AND A MORE STABLE AIR MASS ARE EXPECTED TO CAUSE GRADUAL WEAKENING. IF HENRIETTE MOVES NORTH OF THE CURRENT FORECAST TRACK IT WOULD ENCOUNTER MUCH COOLER SSTS AND LIKELY WEAKEN FASTER THAN INDICATED BELOW. HENRIETTE HAS MADE ITS MUCH ANTICIPATED WEST-NORTHWESTWARD TURN. IT HAS ALSO GAINED SOME FORWARD SPEED WITH AN INITIAL MOTION OF 290/8 KT. HENRIETTE SHOULD MOVE WEST-NORTHWESTWARD TO NORTHWESTWARD TOWARD A BREAK IN THE SUBTROPICAL RIDGE DURING THE NEXT COUPLE OF DAYS. THE TRACK GUIDANCE HAS COME INTO MUCH BETTER AGREEMENT ON THIS CYCLE...AND THE NHC TRACK HAS BEEN ADJUSTED NORTHWARD ONCE AGAIN TO BE NEAR THE MIDDLE OF THE GUIDANCE ENVELOPE. AFTER 48 HOURS...THE MID-LATITUDE TROUGH THAT IS PRODUCING THE WEAKNESS IN THE RIDGE IS EXPECTED TO LIFT OUT WITH THE RIDGE BUILDING WESTWARD ONCE AGAIN. THIS SHOULD CAUSE HENRIETTE TO TURN BACK TOWARD THE WEST DURING THE 3- TO 5-DAY TIME PERIOD. AS HENRIETTE WEAKENS AND BECOMES A SHALLOW CYCLONE...IT IS LIKELY TO MOVE MORE QUICKLY WESTWARD IN THE BRISK LOW-LEVEL EASTERLY TRADES OVER THE CENTRAL PACIFIC. FORECAST POSITIONS AND MAX WINDS INIT 05/2100Z 12.8N 129.0W 55 KT 65 MPH 12H 06/0600Z 13.6N 130.0W 65 KT 75 MPH 24H 06/1800Z 14.8N 131.5W 70 KT 80 MPH 36H 07/0600Z 15.8N 133.1W 75 KT 85 MPH 48H 07/1800Z 16.7N 134.8W 70 KT 80 MPH 72H 08/1800Z 17.5N 138.5W 60 KT 70 MPH 96H 09/1800Z 17.3N 142.5W 50 KT 60 MPH 120H 10/1800Z 17.0N 147.0W 40 KT 45 MPH $$ FORECASTER BROWN