ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM TROPICAL STORM HENRI DISCUSSION NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL AL082015 1100 PM AST THU SEP 10 2015 Henri has changed little in organization during the past several hours. The system continues to have some characteristics of a subtropical cyclone, with the convective banding and strongest winds well away from the center in the northeastern semicircle. The initial intensity remains 35 kt, as there has been no new scatterometer data from the area where the strongest winds are likely occurring. The initial motion is northward or 005/12. Henri should accelerate and turn to the northeast during the next 48 hours as it enters the mid-latitude westerlies. After that time, a quick eastward motion is expected until the cyclone dissipates. The new track forecast is an update of the previous forecast and is just to the right of the various consensus models. The vertical wind shear over Henri is diminishing, so there is a chance that the system could intensify a little before reaching cold water north of the Gulf Stream in about 18 hours. After that, the system should begin extratropical transition as it merges with a frontal system, and this process is expected to be complete in about 36 hours. The cyclone is likely to be absorbed by a larger extratropical system between 72-96 hours. An alternative scenario is that Henri could degenerate to a trough between 24-72 hours as indicated by several of the global models. The latter part of this forecast, when the storm is expected to be post-tropical, is based on guidance provided by NOAA's Ocean Prediction Center. FORECAST POSITIONS AND MAX WINDS INIT 11/0300Z 34.8N 60.7W 35 KT 40 MPH 12H 11/1200Z 37.5N 60.1W 40 KT 45 MPH 24H 12/0000Z 41.2N 58.0W 40 KT 45 MPH 36H 12/1200Z 44.9N 54.5W 40 KT 45 MPH...POST-TROP/EXTRATROP 48H 13/0000Z 47.6N 48.5W 40 KT 45 MPH...POST-TROP/EXTRATROP 72H 14/0000Z 48.0N 33.0W 35 KT 40 MPH...POST-TROP/EXTRATROP 96H 15/0000Z...DISSIPATED $$ Forecaster Beven NNNN