Tropical Cyclone Discussion
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WTPZ45 KNHC 250852

300 AM MDT TUE OCT 25 2016

The small eye of Seymour has reappeared in infrared satellite
imagery overnight, and has warmed and become more distinct within
the past hour or so.  Subjective Dvorak intensity estimates are
T5.5 (102 kt) from TAFB and T5.0 (90 kt) from SAB. Objective Dvorak
intensity estimates from UW/CIMSS are somewhat lower, likely due to
the technique having difficulty in resolving the small eye.  Based
on the very recent warming of the eye, the initial intensity is set
to 100 kt.

Seymour is expected to remain within an area of low wind shear and
over SSTs of around 28C during the next 24 hours.  These conditions
favor additional intensification and the NHC wind speed forecast
calls for a peak intensity at category 4 strength later today.
After that time, increasing southwesterly shear and cooler waters
should begin the weakening process.  Seymour is predicted to weaken
very rapidly between days 2 and 3 when it encounters very strong
southwesterly shear and moves over SSTs below 25C.  The NHC
intensity forecast is near the upper-end of the guidance through
24 hours, but is close to the LGEM and NOAA corrected consensus
models after that time.

The hurricane is moving westward or 280/13 kt.  A mid- to
upper-level ridge extending westward from Mexico is expected to
steer Seymour westward to west-northwestward for another 24 to 36
hours.  After that time, a deep-layer trough is forecast to erode
the western portion of the ridge which should cause Seymour to turn
northwestward, then northward later in the period.  The track
guidance remains in good agreement and the new NHC track forecast
is essentially an update of the previous advisory.

Recent ASCAT data shows that Seymour remains a small tropical
cyclone with tropical-storm-force winds extending only about
60 n mi from the center.


INIT  25/0900Z 15.6N 113.8W  100 KT 115 MPH
 12H  25/1800Z 16.0N 115.9W  115 KT 130 MPH
 24H  26/0600Z 16.6N 118.3W  110 KT 125 MPH
 36H  26/1800Z 17.5N 120.4W   95 KT 110 MPH
 48H  27/0600Z 18.8N 121.8W   80 KT  90 MPH
 72H  28/0600Z 21.2N 122.5W   45 KT  50 MPH
 96H  29/0600Z 22.0N 122.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  30/0600Z...DISSIPATED

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