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TROPICAL STORM IAN DISCUSSION NUMBER  13
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL102016
1100 AM AST THU SEP 15 2016

After looking more like a subtropical cyclone than a tropical
cyclone for most of the past 24 hours, there has recently been an
increase in convective banding over the eastern semicircle of Ian.
The initial intensity remains 45 kt based on a subtropical cyclone
intensity estimate from TAFB.  Ian is forecast to merge with the
westerlies and undergo extratropical transition during the next
36-48 hours, and in the process it is expected to strengthen to at
least storm-force before it is absorbed by another extratropical
low. The new intensity forecast is an update of the previous
forecast based on the global models and guidance from the Ocean
Prediction Center

Ian is accelerating northeastward and the initial motion is now
040/21.  A northeastward motion with an additional increase in
forward speed is expected before the cyclone is absorbed.  The new
forecast track is near the center of the tightly clustered track
guidance.


FORECAST POSITIONS AND MAX WINDS

INIT  15/1500Z 37.2N  50.5W   45 KT  50 MPH
 12H  16/0000Z 40.3N  46.8W   55 KT  65 MPH
 24H  16/1200Z 45.6N  39.6W   60 KT  70 MPH...POST-TROPICAL
 36H  17/0000Z 51.5N  32.0W   60 KT  70 MPH...POST-TROP/EXTRATROP
 48H  17/1200Z...MERGED WITH EXTRATROPICAL LOW

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Forecaster Beven

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