Official Discussion issued by the National Hurricane Center

Jose (AL122017) DATA RELEASED: 9/17/2017 9:00:00 PM UTC

Copy of official data

Hurricane Jose Discussion Number  50
NWS National Hurricane Center Miami FL       AL122017
500 PM EDT Sun Sep 17 2017

The satellite appearance of Jose has generally changed little
during the past several hours.  Microwave data indicate that the
center of circulation is located on the south side of the main area
of deep convection, likely due to strong southerly shear.  The
current intensity is held at 80 kt based on the earlier aircraft
data.  The initial wind radii have been adjusted outward in
accordance with the ASCAT data from a few hours ago.

The strong wind shear currently affecting Jose is expected to
continue for another day or so.  Although the shear is expected to
slacken beyond that time, Jose is forecast to cross the north wall
of the Gulf Stream current by then and move into a progressively
drier environment.  These conditions should cause a slow weakening
trend through the period, and the NHC intensity forecast is largely
an update of the previous one.  It should be noted, however, that
despite the expected weakening, the models suggest that Jose's outer
wind field will expand, which is typical for tropical cyclones that
move into the mid-latitudes.

The hurricane continues to move northward at 8 kt on the west side
of a subtropical ridge.  This general motion is expected to
persist for the next 2 to 3 days while the steering pattern holds.
Thereafter, a turn to the northeast and then east is predicted as a
trough currently over central Canada moves closer to Jose.  This
trough, however, is not expected to pick up Jose, and instead the
cyclone is expected to meander or drift southward by the end of the
forecast period.  The 5-day forecast position has been adjusted to
the southwest of the previous NHC prediction, but otherwise only
minor changes were made.

The Air Force and NOAA Hurricane Hunters will both be investigating
Jose this evening.  This valuable data will help assess the
hurricane's initial intensity and structure, and assist the models
in determining the future path and intensity of the hurricane.

KEY MESSAGES:

1. While the center of Jose is currently forecast to remain offshore
of the U.S. coast, the large cyclone could cause some direct impacts
from Delaware northward to New England, and any deviation to the
left of the NHC forecast track would increase the likelihood and
magnitude of those impacts.  A tropical storm watch is now in
effect from the Delaware coast to southeastern Massachusetts.
Interests elsewhere along the U.S. east coast from North
Carolina to New England should monitor the progress of Jose
through the next several days.

2. Minor to moderate coastal flooding is possible from Delaware
to southern New England during the next several days.  Please see
products issued by local National Weather Service forecast offices.

3. Swells generated by Jose are affecting Bermuda, the Bahamas,
and much of the U.S. east coast. These swells are likely to cause
dangerous surf and rip current conditions for the next several days
in these areas.

4. Jose will produce heavy rain as it passes near southern New
England and the mid-Atlantic on Tuesday and Wednesday.  Total
accumulations of three to five inches are expected over eastern Long
Island, southern Rhode Island, and southeast Massachusetts,
including Martha's Vineyard and Nantucket.  Based on the current
forecast, the risk of flooding will be limited in scope.  Any
deviation to the left of the forecast track, however, could bring
heavier and more widespread rainfall to southern New England, Long
Island, New York City, and New Jersey.  If this deviation
were to occur, the risk of urban flash flooding and some river
flooding would increase.

FORECAST POSITIONS AND MAX WINDS

INIT  17/2100Z 31.5N  71.8W   80 KT  90 MPH
12H  18/0600Z 32.7N  71.7W   80 KT  90 MPH
24H  18/1800Z 34.3N  71.8W   75 KT  85 MPH
36H  19/0600Z 35.9N  71.9W   70 KT  80 MPH
48H  19/1800Z 37.7N  71.6W   65 KT  75 MPH
72H  20/1800Z 40.1N  69.7W   55 KT  65 MPH
96H  21/1800Z 39.7N  67.5W   50 KT  60 MPH
120H  22/1800Z 38.5N  67.0W   50 KT  60 MPH...POST-TROPICAL

$$
Forecaster Cangialosi