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#1059868 (Received by flhurricane at: 4:51 PM 01.Sep.2021) TCDAT2 Tropical Storm Larry Discussion Number 5 NWS National Hurricane Center Miami FL AL122021 800 PM CVT Wed Sep 01 2021 Afternoon satellite imagery indicates that Larry continues to become better organized, with visible imagery hinting at eye formation and a partial SSM/IS overpass suggesting that a 37 GHz convective ring is present around the center. Satellite intensity estimates are now 65 kt from SAB and 55 kt from TAFB, and the initial intensity is increased to 60 kt, which is a 30 kt increase since this time yesterday satisfying the 24-h definition of rapid intensification. The initial motion is now 275/19 kt. Larry is expected to move around the south and southwest sides of a subtropical ridge during the next five days, with a general westward motion for 24-36 h, followed by a turn toward the west-northwest and, by 96-120 h, a turn toward the northwest. The spread in the track guidance after 36 h has decreased a little in the latest model runs. However, the guidance envelope has again shifted a little to the west. The new forecast track will also be shifted a little westward, and it lies on the southern edge of the various consensus models. Conditions appear favorable for additional rapid intensification during at the next 36-48 h, and the intensity forecast now calls for Larry to become a hurricane in less than 12 h and become a major hurricane in about 48 h. Given current trends, this part of the intensity forecast could be conservative. There is lower confidence in the intensity forecast after 48 h. Larry is expected to encounter somewhat increased shear, and around the 72 h point it is expected to encounter some dry air. After 96 h, moderate shear is forecast to continue, but the cyclone is expected to move into a more moist air mass and over increasing sea surface temperatures. On top of these factors, there is the good chance that Larry will have fluctuations in intensity after it becomes a major hurricane due to eyewall replacement cycles. The intensity guidance basically keeps a steady intensity from 60-120 h, and the official forecast follows that trend. However, this part of the intensity forecast is in the middle of the guidance, and it is possible Larry could be stronger than forecast during this time. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 12.5N 29.4W 60 KT 70 MPH 12H 02/0600Z 12.6N 31.8W 70 KT 80 MPH 24H 02/1800Z 13.0N 34.9W 85 KT 100 MPH 36H 03/0600Z 13.7N 38.0W 95 KT 110 MPH 48H 03/1800Z 14.6N 40.9W 100 KT 115 MPH 60H 04/0600Z 15.6N 43.5W 105 KT 120 MPH 72H 04/1800Z 16.9N 46.2W 105 KT 120 MPH 96H 05/1800Z 19.5N 50.5W 105 KT 120 MPH 120H 06/1800Z 22.5N 54.0W 105 KT 120 MPH $$ Forecaster Beven |