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#803428 (Received by flhurricane at: 10:49 AM 24.Sep.2015) TCDAT5 TROPICAL DEPRESSION IDA DISCUSSION NUMBER 25 NWS NATIONAL HURRICANE CENTER MIAMI FL AL102015 1100 AM AST THU SEP 24 2015 There has been no significant change in the satellite presentation of the cyclone. Ida is a sheared system and consists of a broad circulation with a cyclonically curved convective band around the eastern side. Based on a recent ASCAT pass the initial intenisty has been lowered to 30 kt. The hostile shear environment will likely continue today, but both the operational SHIPS and the experimental SHIPS based on ECMWF fields lower the shear allowing for some restrengthening. On this basis, the NHC forecast calls for little change in intensity during the next day or two, and some minor increase of the winds after that time. Ida has begun to move toward the north-northeast at 4 kt. The cyclone will become completely detached from the mid-level trough in about 12 to 24 hours, and will be slowly steered toward the north and north-northwest by the flow surrounding a developing subtropical ridge. After that time, a stronger ridge will force Ida to turn westward with some increase in forward speed. Track guidance is very consistent with this westward turn, however, by then, the status of Ida is highly uncertain. Ida could still be a tropical cyclone as indicated in the NHC forecast or it will be degenerating into a trough as indicated by the GFS. FORECAST POSITIONS AND MAX WINDS INIT 24/1500Z 20.2N 44.9W 30 KT 35 MPH 12H 25/0000Z 20.8N 44.7W 30 KT 35 MPH 24H 25/1200Z 21.5N 45.0W 30 KT 35 MPH 36H 26/0000Z 22.5N 45.5W 30 KT 35 MPH 48H 26/1200Z 23.5N 46.5W 35 KT 40 MPH 72H 27/1200Z 24.5N 48.0W 40 KT 45 MPH 96H 28/1200Z 24.5N 50.0W 40 KT 45 MPH 120H 29/1200Z 24.0N 52.0W 40 KT 45 MPH $$ Forecaster Avila |