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HURRICANE MATTHEW DISCUSSION NUMBER   6
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL142016
500 PM AST THU SEP 29 2016

After the low-level center became nearly exposed this morning, deep
convection has redeveloped over the center.  The overall cloud
pattern of Matthew has become better organized during the day, with
some banding features over the eastern and northern portions of the
circulation.  Thanks to some timely observations from the Air Force
Hurricane Hunters, Matthew was upgraded to a hurricane at 18Z.  This
was based on several believable SFMR-observed surface wind
measurements from the aircraft.  Matthew is forecast to remain in an
environment of 15 to 20 kt of shear into Friday, with some
relaxation of the shear expected by late Friday.  The official
intensity forecast is a little higher than the previous one, and is
a little above the model consensus but close to the latest HWRF
model prediction.

Matthew has not slowed down yet, with the initial motion remaining
westward at 15 kt.  A mid-tropospheric ridge to the north of the
hurricane should maintain a westward to slightly south of westward
motion for the next 48 hours or so.  Then, Matthew is likely to
turn to the right as it nears the western periphery of the ridge,
and head generally northward to the southwest and west of the high
and east of a trough over the Gulf of Mexico late in the forecast
period.  One should not focus on the details of the track at 72 to
120 hours due to the inherent forecast uncertainties.  It should be
noted that the NOAA G-IV aircraft is currently doing a synoptic
surveillance mission to provide data in the environment of Matthew
for initializing the numerical models.  It is hoped that these
additional data will improve the accuracy of tonight's model
runs.

The unusually far south track of Matthew has necessitated the
issuance of a tropical storm watch for a portion of the coast of
Colombia.

FORECAST POSITIONS AND MAX WINDS

INIT  29/2100Z 14.1N  67.8W   65 KT  75 MPH
 12H  30/0600Z 14.0N  69.6W   70 KT  80 MPH
 24H  30/1800Z 13.8N  71.5W   75 KT  85 MPH
 36H  01/0600Z 13.7N  72.7W   80 KT  90 MPH
 48H  01/1800Z 13.7N  73.7W   85 KT 100 MPH
 72H  02/1800Z 15.7N  75.1W   90 KT 105 MPH
 96H  03/1800Z 18.6N  75.5W   90 KT 105 MPH
120H  04/1800Z 22.5N  75.5W   85 KT 100 MPH

$$
Forecaster Pasch/Brown

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