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#803520 (Received by flhurricane at: 11:01 AM 27.Sep.2015) TCDAT5 TROPICAL DEPRESSION IDA DISCUSSION NUMBER 37 NWS NATIONAL HURRICANE CENTER MIAMI FL AL102015 1100 AM AST SUN SEP 27 2015 Ida is very disorganized this morning. Visible satellite images indicate that the circulation of the depression is becoming elongated from north to south, though the low-level center is still distinct. Deep convection is scattered and not organized, and this system is barely classifiable using Dvorak metrics. The initial intensity remains 25 kt. The cyclone is embedded in a dry atmosphere, which is likely the reason why convection is limited. In addition, the interaction with a cold front about 350 n mi to the north of Ida is causing the circulation to become stretched as described above. Since the frontal boundary is expected to move closer to Ida during the next day or so before stalling, it is possible that Ida could open up into a trough during that time. It is also possible that Ida could become a remnant low by then if organized deep convection does not return. Based on the negative factors for the tropical cyclone, prediction of when Ida becomes a remnant low and dissipates have been moved up 24 hours from the previous advisory, and these could occur much sooner than forecast. Ida has jogged a bit to the north recently, but a long-term motion is west-northwestward at about 5 kt. A turn to the west-southwest is expected later today, followed by a faster westward motion tomorrow and Tuesday as a low to mid-level ridge builds to the north of the cyclone. The track guidance has changed little this cycle, and only small changes were made to the previous forecast. FORECAST POSITIONS AND MAX WINDS INIT 27/1500Z 24.8N 48.4W 25 KT 30 MPH 12H 28/0000Z 24.4N 49.3W 25 KT 30 MPH 24H 28/1200Z 23.9N 51.2W 25 KT 30 MPH 36H 29/0000Z 23.8N 53.5W 25 KT 30 MPH 48H 29/1200Z 24.1N 55.9W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 30/1200Z 25.0N 59.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 01/1200Z...DISSIPATED $$ Forecaster Cangialosi |