Official Discussion issued by the National Hurricane Center

Jose (AL122017) DATA RELEASED: 9/12/2017 11:00:00 PM UTC

Copy of official data

Hurricane Jose Discussion Number  31
NWS National Hurricane Center Miami FL       AL122017
1100 PM AST Tue Sep 12 2017

Recent microwave imagery has revealed that Jose has a fairly sturdy
structure, despite 20-25 kt of northerly shear.  The hurricane has
a well-defined mid-level eye, and a 2241 UTC WindSat pass shows a
well-defined low-level circulation that is slightly eroded on the
northwest side.  Since Dvorak final-T numbers are 4.0 from TAFB and
SAB, the initial intensity remains 65 kt, although it wouldn't be
surprising if the winds were a little stronger than that.  Jose
could strengthen slightly during the next 12-24 hours while it
remains in a regime of northerly shear, and models like the HWRF
and HCCA support that thinking.  After 24 hours, the shear is
expected to turn out of the west-northwest and west directions,
which are less likely to support intensification.  Therefore, the
NHC official forecast follows the trend of the intensity consensus
(IVCN), showing Jose becoming a tropical storm on days 3 through 5.
The ECMWF shows Jose encountering significant westerly shear by day
5, so it's possible that NHC forecast may be a little high toward
the end of the forecast period.

The microwave data indicated that Jose's center is a little more
southeast than previously estimated, and the initial motion
estimate is now 125/8 kt.  Jose is being pushed southeastward on
the back side of a large mid-latitude trough, but this trough will
soon leave Jose behind with the subtropical ridge building in to
its north.  As a result, Jose is expected to make a slow clockwise
loop during the next 3 days and then turn northward and
northeastward once it moves around the western side of the ridge.
Only the UKMET disagrees with this scenario by maintaining a
persistent ridge to the north, and that model is discounted at this
time.  The NHC track forecast lies closest to a consensus of the
GFS and ECMWF for most of the forecast period, and it's only a bit
southwest of the previous forecast through day 3 to account for the
updated initial position.


INIT  13/0300Z 26.5N  66.4W   65 KT  75 MPH
12H  13/1200Z 25.9N  65.6W   70 KT  80 MPH
24H  14/0000Z 25.3N  65.3W   70 KT  80 MPH
36H  14/1200Z 25.2N  66.1W   65 KT  75 MPH
48H  15/0000Z 25.6N  67.4W   65 KT  75 MPH
72H  16/0000Z 27.3N  70.3W   60 KT  70 MPH
96H  17/0000Z 30.0N  70.5W   60 KT  70 MPH
120H  18/0000Z 32.5N  68.5W   60 KT  70 MPH

Forecaster Berg