000
WTPZ45 KNHC 040237
TCDEP5

Tropical Storm Xavier Discussion Number   6
NWS National Hurricane Center Miami FL       EP252018
1000 PM CDT Sat Nov 03 2018

Xavier's overall structure has not changed since this afternoon. The
tropical storm is still strongly sheared and deep convection is
primarily occurring to the northeast of its low-level center. Recent
objective and subjective intensity estimates range from 45 to 50 kt.
Earlier ASCAT data explicitly contained several vectors near 45 kt,
but the instrument could have under-sampled the maximum winds. Based
on all these data, 50 kt seems most representative of the tropical
storm's intensity at this time.

Regardless of Xavier's exact maximum winds, it is likely nearing its
peak intensity now. Some slight additional strengthening in the
short term can not be ruled out, however the global models indicate
that strong wind shear will continue through the forecast period and
the flow aloft will become less supportive for convection by late
Sunday or early Monday. All of the intensity models forecast that
Xavier will begin to weaken in about 24 h. By 96 h, if not sooner,
the dynamical models indicate that Xavier will lose all deep
convection and become a remnant low. Virtually no change was made to
the official intensity forecast, which is merely an update of the
previous advisory.

Xavier is now moving toward the northeast, and the initial motion
estimate is 035/6 kt. With the continued exception of the UKMET
model, the typically reliable track guidance is in good agreement
on the track of the tropical storm. The cyclone will likely turn
northward tonight or tomorrow, and is then forecast to turn steadily
westward in another day or two as it weakens and becomes vertically
shallow. The UKMET does not show this turn and shows a
stronger/deeper Xavier that moves farther north, though this
scenario appears unlikely given the strong agreement among the
intensity models that Xavier will weaken. Only minor adjustments
were made to the NHC track forecast, which blends the previous
official forecast with the HCCA and GFEX consensus aids at most
forecast hours.


FORECAST POSITIONS AND MAX WINDS

INIT  04/0300Z 16.1N 105.7W   50 KT  60 MPH
 12H  04/1200Z 16.7N 105.6W   50 KT  60 MPH
 24H  05/0000Z 17.4N 105.9W   45 KT  50 MPH
 36H  05/1200Z 17.8N 106.6W   40 KT  45 MPH
 48H  06/0000Z 17.9N 107.7W   35 KT  40 MPH
 72H  07/0000Z 18.1N 110.1W   30 KT  35 MPH
 96H  08/0000Z 18.3N 112.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  09/0000Z 18.5N 115.0W   20 KT  25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Zelinsky