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#536472 (Received by flhurricane at: 10:38 PM 23.Aug.2012) TCDAT5 TROPICAL DEPRESSION JOYCE DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL AL102012 1100 PM AST THU AUG 23 2012 CONVECTION HAS NOT REFORMED NEAR THE LOW-LEVEL CENTER OF JOYCE...AND SATELLITE DATA SHOW THAT IT REMAINS EXPOSED WELL TO THE SOUTH OF ITS DYING MID-LEVEL CIRCULATION. AN ASCAT PASS AROUND 0000 UTC SUGGESTED MAXIMUM WINDS OF 25-30 KT...SO 30 KT WILL BE USED AS THE INITIAL INTENSITY. ALTHOUGH THE CYCLONE WILL BE MOVING OVER PROGRESSIVELY WARMER WATERS...MODERATE OR STRONG SOUTHERLY SHEAR IS LIKELY FOR THE NEXT COUPLE OF DAYS. THESE CONDITIONS SHOULD NOT ALLOW FOR MUCH STRENGTHENING...SO LITTLE CHANGE IS SHOWN DURING THAT TIME. IN A FEW DAYS...JOYCE COULD BE POSITIONED IN A LIGHTER SHEAR ENVIRONMENT TO THE NORTH OF AN UPPER-LEVEL LOW. THUS...SOME INTENSIFICATION WILL BE SHOWN AT LONG RANGE...WHICH IS CONSISTENT WITH THE SHIPS MODEL AND THE PREVIOUS FORECAST. IT IS WORTH MENTIONING THAT...CONSIDERING THE MARGINAL ENVIRONMENT...IT WOULD NOT BE SURPRISING IF JOYCE DEGENERATED INTO A REMNANT LOW SOMETIME DURING THE NEXT DAY OR TWO. THE DEPRESSION APPEARS TO BE MOVING ABOUT THE SAME AS BEFORE... 300/12. JOYCE SHOULD ACCELERATE TO THE NORTHWEST OVER THE NEXT DAY OR SO AS IT MOVES INTO FASTER FLOW BETWEEN A RIDGE OVER THE CENTRAL ATLANTIC AND A TROUGH EAST OF THE LEEWARD ISLANDS. A TURN TO THE NORTH AND NORTHEAST SHOULD OCCUR AFTER DAY 3 AS THE CYCLONE ROUNDS THE WESTERN PERIPHERY OF THE RIDGE. THE MODEL GUIDANCE IS IN RELATIVELY GOOD AGREEMENT ON THIS SCENARIO WITH ONLY SOME MINOR DIFFERENCES. THE OFFICIAL FORECAST IS BASICALLY AN UPDATE OF THE PREVIOUS ONE FOR THE FIRST COUPLE OF DAYS...THEN IS ADJUSTED TO THE LEFT DURING RECURVATURE IN THE LONG RANGE. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 16.3N 43.7W 30 KT 35 MPH 12H 24/1200Z 17.4N 46.0W 30 KT 35 MPH 24H 25/0000Z 18.9N 48.9W 30 KT 35 MPH 36H 25/1200Z 20.7N 52.2W 30 KT 35 MPH 48H 26/0000Z 22.8N 55.5W 30 KT 35 MPH 72H 27/0000Z 27.0N 62.0W 35 KT 40 MPH 96H 28/0000Z 31.5N 64.5W 45 KT 50 MPH 120H 29/0000Z 36.0N 58.0W 50 KT 60 MPH $$ FORECASTER BLAKE |