000 WTNT42 KNHC 140837 TCDAT2 HURRICANE JULIA DISCUSSION NUMBER 8 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL122010 500 AM AST TUE SEP 14 2010 JULIA HAS STRENGTHENED THIS MORNING. A RAGGED EYE FEATURE HAS OCCASIONALLY BEEN EVIDENT IN GEOSTATIONARY SATELLITE IMAGES DURING THE PAST FEW HOURS AND THE CONVECTIVE BANDING HAS BECOME BETTER ORGANIZED...ESPECIALLY OVER THE SOUTHERN SEMICIRCLE. DVORAK CLASSIFICATIONS FROM TAFB AND SAB WERE 65 KT...AND THE CIMSS ADT ESTIMATES ARE ALSO NEAR THAT VALUE. ON THIS BASIS...JULIA IS UPGRADED TO A HURRICANE WITH THE INITIAL WIND SPEED SET AT 65 KT. SOME ADDITIONAL STRENGTHENING APPEARS LIKELY DURING THE NEXT DAY OR SO AS UNANIMOUSLY SHOWN BY THE MODEL GUIDANCE. HOWEVER...SEA SURFACE TEMPERATURES COOL BELOW 27 C ALONG THE FORECAST TRACK IN 24 TO 48 HOURS...AND THAT SHOULD LIMIT INTENSIFICATION DURING THAT TIME PERIOD. ALTHOUGH JULIA IS EXPECTED TO TRACK OVER WARMER WATERS BEYOND A FEW DAYS...STRONG NORTH TO NORTHEASTERLY SHEAR... ASSOCIATED WITH THE OUTFLOW OF HURRICANE IGOR...SHOULD INDUCE WEAKENING BY THAT TIME. THE OFFICIAL FORECAST IS ADJUSTED UPWARD DURING THE FIRST FEW DAYS AND THEN FALLS IN LINE WITH THE PREVIOUS FORECAST BY THE END OF THE PERIOD...AND IS IN GOOD AGREEMENT WITH THE STATISTICAL-DYNAMICAL GUIDANCE. THE INITIAL MOTION ESTIMATE IS 295/10. A MID- TO UPPER-LEVEL TROUGH OVER THE EASTERN ATLANTIC IS EXPECTED TO CAUSE JULIA TO TURN NORTHWESTWARD LATER TODAY AND CONTINUE IN THAT DIRECTION FOR THE NEXT 24 TO 48 HOURS. THEREAFTER...THE GLOBAL MODELS ARE IN AGREEMENT IN SHOWING A SUBTROPICAL RIDGE TO STRENGTHEN NORTH OF JULIA. THIS PATTERN SHOULD CAUSE THE CYCLONE TO TURN BACK TO THE WEST-NORTHWEST FOR A COUPLE OF DAYS. BY THE END OF THE FORECAST PERIOD...JULIA IS EXPECTED TO MOVE NORTHWESTWARD OR NORTH-NORTHWESTWARD ALONG THE WESTERN PERIPHERY OF THE RIDGE. THE OFFICIAL FORECAST IS ADJUSTED SLIGHTLY TO THE WEST IN THE 3 TO 5 DAY RANGE...TRENDING TOWARD THE MULTI-MODEL CONSENSUS. FORECAST POSITIONS AND MAX WINDS INITIAL 14/0900Z 16.1N 29.0W 65 KT 12HR VT 14/1800Z 16.8N 30.1W 70 KT 24HR VT 15/0600Z 18.1N 31.7W 80 KT 36HR VT 15/1800Z 19.7N 33.6W 80 KT 48HR VT 16/0600Z 21.5N 36.1W 75 KT 72HR VT 17/0600Z 24.5N 42.5W 70 KT 96HR VT 18/0600Z 27.5N 48.5W 60 KT 120HR VT 19/0600Z 32.0N 51.0W 50 KT $$ FORECASTER CANGIALOSI