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#1059097 (Received by flhurricane at: 4:50 PM 28.Aug.2021) TCDAT5 Tropical Depression Ten Discussion Number 3 NWS National Hurricane Center Miami FL AL102021 500 PM AST Sat Aug 28 2021 This afternoon`s satellite presentation consists of an exposed surface circulation with a rather shapeless convective mass displaced to the east and north of the center. Without question, the 15 to 20 kt of west-northwesterly shear is doing a number on the cloud pattern. Also evident, are a number of arc clouds propagating away from the system`s deep convection, certainly indicative of dry air intrusion. Consequently, the initial intensity is once again held at 30 kt for this advisory. The global models as well as the Decay SHIPS (ECMWF/GFS) intensity guidance still show the shear relaxing a bit tonight and into Sunday, which should allow the depression to briefly become a tropical storm. By Monday, however, the shear is forecast to increase while the cyclone moves into an even more dry and stable air mass. These inhibiting contributions should stifle further strengthening and weaken the cyclone back to a depression through the remainder of the forecast period. It`s worth mentioning that the GFS indicates that the depression will become a remnant low in 72 hours while turning northwestward to west-northwestward within the tradewind flow and dissipate by the end of the week. For now, the NHC forecast will stick with the consensus intensity models and the SHIPS guidance which agree on maintaining a depression through day 5. The initial motion is estimated to be northward, or 360/7 kt. The depression remains embedded in low- to mid-level southerly flow produced by a mid-Atlantic trough dominating the central Atlantic. This synoptic feature, along with a subtropical high pressure located over the east Atlantic and western Africa, should influence a generally northward motion through the 5-day period. The official track forecast again is adjusted a little to the right of the previous advisory beyond day 3, and lies between the TVCN and HCCA multimodel solutions. FORECAST POSITIONS AND MAX WINDS INIT 28/2100Z 15.6N 50.0W 30 KT 35 MPH 12H 29/0600Z 16.6N 50.0W 35 KT 40 MPH 24H 29/1800Z 18.2N 49.9W 35 KT 40 MPH 36H 30/0600Z 19.8N 49.7W 30 KT 35 MPH 48H 30/1800Z 21.3N 49.3W 30 KT 35 MPH 60H 31/0600Z 22.5N 48.8W 30 KT 35 MPH 72H 31/1800Z 23.8N 49.0W 30 KT 35 MPH 96H 01/1800Z 27.2N 50.5W 30 KT 35 MPH 120H 02/1800Z 30.5N 51.5W 30 KT 35 MPH $$ Forecaster Roberts |