Official Discussion issued by the National Hurricane Center

Joyce (AL102018) DATA RELEASED: 9/18/2018 5:00:00 AM UTC

Copy of official data

Tropical Depression Joyce Discussion Number  23
NWS National Hurricane Center Miami FL       AL102018
500 AM AST Tue Sep 18 2018

The latest convective burst associated with Joyce is weakening due
to the effects of 35-40 kt of westerly vertical shear and very dry
mid-level air.  Satellite intensity estimates have changed little
since the previous advisory, so the initial intensity remains 30
kt.  The cyclone is expected to gradually weaken due to the ongoing
shear and dry air entrainment, and the new intensity forecast again
calls for the system to become a remnant low in 12-24 h. Dissipation
of the remnants is forecast in 72-96 h in agreement with the global
model guidance.  As indicated in the previous discussion, there is
an alternative scenario where interaction with an upper-level trough
seen in water vapor imagery to the northwest of Joyce maintains
organized convection longer than currently forecast.

The initial motion is now 165/5.  Joyce is forecast to move around
the eastern periphery of a deep-layer ridge located across the
eastern Atlantic, with the cyclone or its remnants turning
southwestward during the next 36 h and westward by 72 h.  The new
forecast track generally lies between the TVCA and HCCA consensus


INIT  18/0900Z 32.9N  27.6W   30 KT  35 MPH
12H  18/1800Z 32.0N  27.7W   30 KT  35 MPH
24H  19/0600Z 31.0N  28.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
36H  19/1800Z 30.3N  29.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
48H  20/0600Z 29.8N  31.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
72H  21/0600Z 29.5N  34.5W   20 KT  25 MPH...POST-TROP/REMNT LOW
96H  22/0600Z...DISSIPATED

Forecaster Beven